TEST: Keeley Blues Disorder

 The Keeley Blues Disorder pedal is a double pedal in which two well-known overdrive pedals have been merged into a single pedal using two circuits.

The construction of Keeley Blues Disorder

You might think that there is now pretty much every single pedal on the market that you can even remotely imagine. So what do you do if you're an established pedal designer and still want to take your products to a new level? You go and take two well-known pedals from the competition, construct two separate circuits and make them accessible on just one pedal via mini switches. This is what Robert Keeley and his team did with the Keeley Blues Disorder pedal, in which two very well-known pedals, the Marshall Blues Breaker and the OCD from Fulltone, are merged into a single pedal.

There are also two further plus points. On the one hand in the form of the fact that you only need half the space on your pedalboard to be able to access two classic blues-rock sounds and on the other hand you only have about half the costs that you would otherwise have to access for two pedals .

The structure of Keeley Blues Disorder

Several points ensure that a certain aha effect arises as soon as you get to grips with the pedal. The structure is quite classic, meaning it has three pleasantly stiff controls that regulate the level, tone and drive, all packed into a clear, classic housing that is very solid. The pedal is also manufactured in the USA and has an LED for the status display and a special feature in the foot switch area.

The footswitch is designed as both true bypass and buffered bypass, depending on whether the pedal is active or not. This combines the two features that, on the one hand, you do not want the sound of the pedal to have an influence on the other devices in bypass mode, but on the other hand, you also want to avoid the increased resistance that inevitably occurs due to the length of the cable when the pedal is in operation. balances.

The real special feature, however, takes place behind the two mini switches, which are each located below the tone and drive controls. On the left side you can set a more or less unprocessed frequency range by moving the mini switch up, which goes towards Marshall Blues Baker. If you switch the mini switch down, you increase the midrange in OCD style by approx. 20 dB, which causes a very strong boost in both volume and frequency range with an accompanying increase in distortion.

Using the right mini-switch you can switch up between soft clipping, again in Bluesbreaker style, or switch down with hard clipping in OCD style. Depending on how the other three controls are set, you have a very large choice of sound and you can basically say that you have more or less four pedals combined in one pedal.

The normal input and output are located on the front of the Keeley Blues Disorder in the form of jack sockets. In between is the mains connection, which is designed at 9 volts, but can also be increased to up to 18 V if necessary with a correspondingly changed sound response. Battery operation is not provided, although the pedal only has a current consumption of 29 mA.

The Sound of Keeley Blues Disorder

I have to get straight to the point, the pedal sounds excellent. Both in the rather soft Bluesbreaker orientation and in the rather hard OCD response, the pedal impresses with very good interaction between instrument and amplifier. The way it works together with the guitar's volume control is exemplary and the two basic sounds set are legendary anyway. In addition, the originals are achieved very well in terms of the tonal aspect.

Through clever experimentation, you can set up the two typical areas of application of these two overdrive and distortion pedals exactly as you would expect from a corresponding pedal. Both work particularly well in front of an amplifier that is set to completely clean or slightly crunchy, so that you can ultimately add a second channel to the amp or use the pedal to boost a basic sound for lead sounds or heavy use.

The pedal is convincing in all respects and if you want to give the pedal any negative point, it would be the fact that you unfortunately cannot switch between the two sounds using the foot switch, which would be the absolute highlight of the pedal. But who knows, maybe there will be an MK2 version of the pedal in a few months or years.

The sound files were created with a Hagström Super Swede via a Sound City Master One Hundred, a 412 Marshall cabinet with Celestion G12 T 75 speakers and 2 pcs. Recorded with Shure SM 57 microphones.

Conclusion

With the Keeley Blues Disorder, the American manufacturer has a very good 4 in 1 pedal in its portfolio. The adaptation of the two original products, Blues Breaker and OCD, works very well and ensures a wide range of good sounds.

Be sure to check it out.

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Additional Informations:

In the vast world of music, the search for the perfect sound has led musicians to an endless array of tools and gadgets. Among these, guitar pedals stand out as pivotal in shaping the tones that define genres and eras. Keeley Electronics, founded by Robert Keeley, has become a beacon for those in pursuit of exquisite audio quality. This article delves into the fascinating journey of Keeley Pedals, tracing its roots, milestones, and the innovations that cemented its place in the music industry.

#### Early Beginnings: Robert Keeley's Background
Robert Keeley's passion for electronics and music began early. Born in the late 1960s, Keeley grew up during a time when rock and roll was evolving rapidly. His fascination with music and technology led him to pursue studies in electrical engineering. His academic background provided him with the technical expertise necessary to understand and manipulate sound at a granular level. Keeley's early work involved repairing and modifying guitar amplifiers, which honed his skills and deepened his understanding of audio circuits.

#### The Birth of Keeley Electronics
Keeley Electronics was officially founded in 2001. The inception of the company was driven by Keeley's desire to create high-quality, reliable effects pedals that addressed the shortcomings he observed in the market. The early 2000s were a transformative period for the music industry, with digital technology starting to make significant inroads. Keeley, however, saw the enduring value in analog circuits and aimed to blend traditional craftsmanship with innovative designs.

The company's first product was the Keeley Compressor, which quickly garnered attention for its superior sound quality and build. Unlike many mass-produced pedals, Keeley's products were hand-assembled and rigorously tested, ensuring consistent performance and durability. The success of the Keeley Compressor laid the foundation for the company's reputation as a producer of premium guitar effects.

#### Key Innovations and Products
Keeley's approach to pedal design is characterized by meticulous attention to detail and a deep understanding of musicians' needs. Over the years, Keeley Electronics has introduced several groundbreaking products that have set new standards in the industry.

1. **Keeley Compressor (2001)**
   The Keeley Compressor is arguably the pedal that put Keeley Electronics on the map. It was celebrated for its ability to maintain the integrity of the guitar's tone while providing smooth, musical compression. The pedal's popularity was fueled by endorsements from high-profile guitarists and its frequent appearance in gear reviews.

2. **Keeley Katana Blues Driver (2002)**
   Following the success of the Compressor, Keeley introduced the Katana Blues Driver. This pedal became famous for its transparent overdrive, allowing guitarists to add grit and sustain without losing the character of their instrument's sound. The Katana was another hit, solidifying Keeley's reputation for producing pedals that enhance, rather than mask, the guitar's natural tone.

3. **Keeley MOD Plus Pedals (2003-2005)**
   Keeley also became known for his modification services. He offered "MOD Plus" versions of popular pedals from other manufacturers, such as the Boss DS-1 Distortion and the Ibanez Tube Screamer. These modified pedals featured upgraded components and circuitry improvements, which enhanced their performance and reliability. The success of these modifications demonstrated Keeley's deep understanding of audio circuits and his ability to innovate upon existing designs.

4. **Keeley Caverns Delay Reverb (2015)**
   In 2015, Keeley released the Caverns Delay Reverb, a pedal that combined two essential effects in one unit. The Caverns became popular for its lush, ambient soundscapes and its versatility, making it a favorite among guitarists looking to expand their sonic palette. The success of the Caverns highlighted Keeley's ability to create complex, multi-function pedals that maintained high audio quality.

#### Expansion and Evolution
As Keeley Electronics grew, the company expanded its product line to include a wide range of effects, from overdrives and distortions to modulations and delays. Keeley's commitment to quality remained unwavering, with each pedal undergoing rigorous testing and quality control.

In addition to expanding its product line, Keeley Electronics also invested in research and development. This investment led to the creation of new technologies and innovations that kept the company at the forefront of the industry. For example, Keeley's work on digital signal processing (DSP) allowed the company to create pedals that combined the warmth and character of analog circuits with the versatility and precision of digital technology.

#### Artist Collaborations and Endorsements
One of the factors that have contributed to Keeley's success is its strong relationships with artists. From the beginning, Keeley sought feedback from professional musicians to refine and improve his designs. These collaborations have resulted in pedals that are not only technically superior but also meet the practical needs of working musicians.

High-profile guitarists such as John Mayer, Brad Paisley, and David Gilmour have used Keeley pedals, providing valuable endorsements that have boosted the company's credibility and visibility. Keeley's willingness to listen to and collaborate with artists has ensured that his products remain relevant and desirable in a constantly evolving market.

#### Community and Culture
Keeley Electronics is not just a company; it's a community. Robert Keeley's commitment to customer service and his genuine passion for music have fostered a loyal following among guitarists. Keeley's presence at trade shows, guitar clinics, and online forums has helped to build a sense of community around the brand. This engagement has created a feedback loop, where customer input directly influences product development.

The company also places a strong emphasis on education. Keeley and his team regularly produce content that explains the technical aspects of their pedals, helping musicians to understand how to get the most out of their gear. This educational approach has further solidified Keeley's reputation as a trustworthy and knowledgeable source in the world of guitar effects.

#### Challenges and Resilience
Like any company, Keeley Electronics has faced its share of challenges. The rapidly changing music industry, economic fluctuations, and the pressures of maintaining high standards of quality have all tested the company's resilience. However, Keeley's commitment to innovation and quality has allowed the company to navigate these challenges successfully.

One significant challenge has been the competition from larger, mass-produced pedal manufacturers. Keeley Electronics has maintained its competitive edge by focusing on niche markets and offering products that cater to discerning musicians. By emphasizing quality over quantity, Keeley has been able to build a brand that stands out in a crowded marketplace.

#### Looking Ahead: The Future of Keeley Electronics
As Keeley Electronics moves forward, the company continues to innovate and expand its product line. The integration of digital technology with analog circuits remains a key focus, as Keeley seeks to create pedals that offer the best of both worlds. Additionally, the company is exploring new markets and opportunities, such as collaborating with other manufacturers and expanding its presence in international markets.

Robert Keeley's passion for music and electronics shows no signs of waning. As the company looks to the future, it remains committed to its core values of quality, innovation, and customer satisfaction. Keeley's journey from a small repair shop to a renowned pedal manufacturer is a testament to the power of dedication and a love for music.

#### Conclusion
The story of Keeley Pedals is one of passion, innovation, and a relentless pursuit of excellence. From its humble beginnings to its status as a leading name in the industry, Keeley Electronics has made a lasting impact on the world of music. Through a commitment to quality, an understanding of musicians' needs, and a willingness to embrace new technologies, Keeley has created products that stand the test of time. As the company continues to evolve, it remains a beacon for those in search of the perfect sound.

TEST: Mackie Thump 12A-15A

 Never change a running system, or to put it another way, never change a box office hit, at most modify it. Similar thought processes must have gone through the minds of Mackie's engineers when they brought the current successor to the successful series onto the market with the Mackie Thump 12A and 15A. So what should you change about a well-performing product to make it a little simpler, easier or perhaps just prettier for the user? Let's take a closer look at the two protagonists in more detail.

Construction and construction

OK, I admit, I had to smile at the first thought that popped into my head while unpacking the components. Battlestar Galactica? The Cylons attack? No, the statement is of course completely exaggerated, but the rounded shapes of its predecessors are now followed by hard edges in the current series, which reminds me of the silver puppet troupe from the seventies, especially from the rear view. In return, stackability increases significantly and, even with daisy chain operation, several housings can be better put together to form a compartment.

The concept of the full-range boxes has remained the same. Depending on the version, a 12 or 15 inch speaker takes care of the bass range, while a 1.4 inch tweeter with a titanium compression driver dome covers the high frequency range. We separated at 2 kHz. The frequency response is given as 50 Hz - 23 kHz (12A) and 32 Hz - 23 kHz (15A), although we all know from practice that all products of this type have long since abandoned linearity below 100 Hz, even a newborn The hearing power does not exceed 20 kHz. But consumers love numbers and it always reads so beautifully.

Which brings us to the next power point. According to the sticker on the front, both systems deliver 1300 watts peak, with 1000 watts being delivered to the woofer via a Class D power amplifier and 300 watts to the tweeter via a Class A/B power amplifier. Here you can safely smile a second time if you take the appropriate but not specified RMS or even sine values as a reference, but see the last paragraph.

Due to the stable but comparatively light plastic housing, the boxes with dimensions of 615 x 358 x 356 mm weigh only 15.4 kilograms (12A), or 686 x 442 x 356 mm and 18.3 kilograms ( 15A). The flexible orientation in terms of operating modes has also remained, so the speakers can be operated in standard operation, in high stand mode via the internally installed commercially available 35 mm flange or, due to the trapezoidal shape, also as a floor monitor. Despite the indicated holes, flight operations are not possible with the Mackie Thump 12A and 15A, but are reserved for the next higher variant, the Mackie Thump 12BST and 15BST.

Connections and concept

To my knowledge, the plug-and-play concept has rarely been implemented as consistently in a product from the sound reinforcement industry as with the Mackie Thump 12A and 15A. Starting with a manual, which includes printing of contact addresses and all legal obligations in 4 languages with only 12 pages of DIN A4, to the fact that the products do not have any sound control. Instead, the Mackie Thump 12A and 15A have four permanently configured modes called Music, Live, Monitor and Subwoofer. In the music area there is a slight scoop, the live area is comparatively linear, the monitor cuts the bass and high mids for the purpose of feedback loops and in the subwoofer Mackie puts a very steep high pass at around 120 Hz into the frequency response. The operating modes can be accessed one after the other using a pressure switch. In addition to the pressure switch, another switch allows you to deactivate the operating LED in order not to disturb presentations that place great value on appearance.

The Mackie Thump 12A and 15A have two combination sockets as connections, each of which has its own gain control. The designations Line, U (0 dB) and Mic were printed as a rough guide; there is no exact designation or an overload display in the preamplifier. Your ears have to do it. A common master volume control regulates the final volume, which has a clip LED. To the right of the combination sockets there is an XLR out for daisy chain operation, power switch, cold device plug with integrated universal power supply (100-240V AC), and that's it.

Practice

Let's start with the basic sound of the product. In contrast to its predecessor, Mackie emphasizes that they have built more power and a more pronounced bass reproduction into their Thump products. This is correct. The previous 200 watt sine wave is now available with around 400 watt sine wave (???), which actually allows for greater headroom, especially in the bass range. Up until just before the clipping area, the bass reproduction remains concise and crisp, allowing for a voluminous sound for this size of speaker.

The treble range is a little harder and sharper, which is also due to the area of use. The Thump series is not a studio monitor, whose resolution and depth graduation are as fine as possible are a must. Rather, it's about acoustically illuminating as many square meters as possible, which is a completely different premise. Mackie succeeds in this very well, even though everything outside of around 60 degrees in the treble range is actually no longer captured. Here you would most likely get 2 pieces each. Grab boxes on each side to get the problem under control.

As expected, the 15A version has a slightly higher bass content, while the slightly faster 12-inch bass speaker captures the center hole at around 2 kHz a little better than the heavier 15-inch speaker. There is no winner, it is advisable to check both variants and choose your personal favorite.

Mackie's selling point is that it can process all signals within the Thump family without any effort, be it a directly connected microphone, a line signal such as a keyboard, a string instrument such as a bass or an MP3 player. This can generally be answered with “yes” first, but followed by a big “but”. What every experienced sound person already knows may throw some beginners back a bit in their budget planning.

The Mackie Thump 12A and 15A basically “just make noise” and they do it well. However, when it comes to sound shaping, it is actually not possible to adequately amplify a microphone with an XLR input and a gain control as well as a volume control. The principle may still work to make a quick loud announcement or to acoustically hit customers with your goods in the style of a weekly market, but within a band context with singing, this minimalism reaches its limits.

The lack of even rudimentary filters cannot influence the sound of the signal in terms of microphone coloring or the vocal context, not to mention further dynamic signal processing such as compressors. It is therefore urgently advisable to include a suitable multi-channel mixer and suitable peripherals in your financial planning; this is the only way the speakers can show off their strengths. The “Live” preset, which is set almost linearly at the factory, in conjunction with the “U” position, speaks volumes.

If you ultimately only leave the volume to the Thump series and see the remaining presets as a good bonus for quick use, the speakers are really convincing, especially for this price.


Conclusion

With the Mackie Thump 12A and 15A series, America's best-known mixer manufacturer impresses in many ways. Conceptually designed for plug-and-play, almost all sound sources can be connected and amplified within seconds, with improved bass management and higher power output making its predecessor pale.

If you now take the time to optimize the signals present using external mixers and signal management, the Thump series can fulfill its actual function of “making loud” in the best possible way.

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Additional Informations:

## The History of 2-Way Loudspeakers in the PA Industry: A Comprehensive Overview

Two-way loudspeakers have become a staple in the professional audio (PA) industry, providing clear, high-quality sound for a wide range of applications, from live concerts and music festivals to conferences and corporate events. Their widespread adoption can be attributed to their ability to deliver a well-balanced soundscape that caters to both low and high frequencies, making them versatile and suitable for various acoustic environments.

The evolution of 2-way loudspeakers in the PA realm is an intriguing narrative that intertwines technological advancements with the ever-changing demands of sound reinforcement. To fully grasp the significance of these speakers, it's essential to delve into their history, understanding the factors that shaped their design and contributed to their dominance in the PA landscape.

### The Early Days: Laying the Foundation for Two-Way Sound

The concept of two-way loudspeaker systems can be traced back to the early 20th century, with the invention of the first electrical loudspeakers. These early designs were rudimentary, often consisting of a single cone driver responsible for reproducing the entire audio spectrum. However, as the demand for higher-fidelity sound grew, the limitations of these single-driver systems became apparent.

In the 1920s, advancements in loudspeaker technology led to the development of multi-driver systems, paving the way for the emergence of two-way loudspeakers. These early two-way systems typically employed a combination of a woofer (for low frequencies) and a tweeter (for high frequencies), each specialized to handle their respective portion of the audio spectrum.

### Pioneering Efforts and Technological Milestones

The 1930s and 1940s witnessed significant advancements in two-way loudspeaker technology, driven by the efforts of pioneering engineers and companies. Altec Lansing, JBL, and Electro-Voice were among the early innovators, introducing groundbreaking loudspeaker designs that pushed the boundaries of sound quality and performance.

A notable milestone in the history of two-way loudspeakers was the development of the coaxial loudspeaker in the 1940s. This innovative design placed the tweeter directly in the voice coil of the woofer, resulting in improved dispersion and phase coherence. Coaxial loudspeakers quickly gained popularity in PA applications, particularly for vocal reinforcement.

### The Rise of Two-Way Loudspeakers in the PA Industry

The post-World War II era saw a surge in the popularity of two-way loudspeakers in the PA industry. This was fueled by several factors, including:

* **Improved Sound Quality:** Two-way loudspeakers offered a significant improvement in sound quality compared to single-driver systems, providing a more balanced and detailed soundscape.

* **Versatility:** Two-way loudspeakers proved versatile, suitable for a wide range of PA applications, from small venues to large outdoor concerts.

* **Portability:** Advancements in loudspeaker design led to more compact and lightweight two-way systems, making them easier to transport and set up.

As a result of these factors, two-way loudspeakers became the go-to choice for sound reinforcement professionals, replacing single-driver systems in many applications.

### The Modern Era: Refinements and Innovations

The modern era of two-way loudspeakers has been characterized by continuous refinement and innovation. With the advent of new materials, manufacturing techniques, and computer-aided design tools, loudspeaker engineers have been able to push the performance boundaries of two-way systems.

Key advancements in modern two-way loudspeaker design include:

* **Improved Driver Technology:** Woofers and tweeters have undergone significant improvements in terms of efficiency, power handling, and frequency response.

* **Advanced Crossover Networks:** Crossover networks, which divide the audio signal between the woofer and tweeter, have become more sophisticated, ensuring seamless transitions between frequency ranges.

* **Speaker Enclosure Design:** Enclosure design has evolved, with a focus on optimizing airflow, reducing resonances, and improving overall sound dispersion.

### Conclusion: Two-Way Loudspeakers – A Cornerstone of PA Technology

Two-way loudspeakers have firmly established themselves as a cornerstone of PA technology, providing a versatile and high-quality sound solution for a diverse range of applications. Their ability to deliver clear, balanced sound across the frequency spectrum has made them indispensable for sound reinforcement professionals worldwide.

As technology continues to advance, two-way loudspeakers are poised to remain at the forefront of PA innovation, with further refinements and advancements in driver design, crossover technology, and enclosure materials. The future of two-way loudspeakers is undoubtedly bright, ensuring that they will continue to play a pivotal role in shaping the soundscapes of live performances, events, and installations for years to come.

TEST: Mackie TH-15A

 Maybe it's just a subjective perception on my part, but it's slowly starting to seem to me as if the days of passive loudspeaker designs in the small P.A. and vocal systems sector are numbered. It definitely makes sense if you take a closer look at the design-related peculiarities of the fused power amplifier/loudspeaker combination in one housing.

Not only is there no need to transport the external power amplifier in the 19-inch format, along with cabling, but the space required both in the transporter and on stage is also significantly reduced. Especially in the area of discreet sound reinforcement at private parties or company anniversaries, where every case more or less represents a visual faux pas, minimizing the tools on stage is a must!

In order to still be able to offer a voluminous sound with the appropriate air movement, fully-fledged multi-way constructions have recently appeared more and more often, sometimes with a 15-inch model in the bass range, but these also often have to deal with the problem of transport weight have to beat.

In order to overcome this problem, Mackie has consistently focused on the issue of weight in its TH-15A product and tried to ensure the fusion of performance with low weight using various components. That makes you curious.


construction

The Mackie TH-15A is an active two-way box. In terms of performance, the product generates 200 watts sine wave with a peak of 400 watts, with a 15 inch bass speaker being operated with a 150 watt Class D power amplifier, while the 1 inch tweeter driver is operated with a Class AB power amplifier. Separation occurs at 3 kHz. In order to support the bass a little more, the construction is designed as a bass reflex.

In addition to the comparatively small Class D power amplifier, the very light housing made of polypropylene ensures that the product only has a total weight of 16.3 cm despite the above-mentioned performance specifications and the housing dimensions of 68.9 cm x 42.7 cm x 40.1 cm kilogram!

The area of application ranges from the classic vocal system to the floor monitor area (trapezoidal shape!) to the full-fledged club P.A. with appropriate daisy chain operation of several individual components. The box can even be used as a moderate drum fill in a pinch, provided the drummer doesn't play in a Motörhead tribute band.


In terms of transport, the product has three handles or recessed grips, two on the outside and one on the top. Due to the convenient placement and the weight mentioned above, a man of average strength can easily transport this box alone without exposing himself to the risk of back pain.

The construction has four stacking troughs on the top and bottom, which should, however, be treated with a little caution. For a well-situated event, the tilting is sufficient to place two boxes safely on top of each other. However, if you are dealing with a throbbing mosh pit in front of the stage, with one or the other tumbling against a sound system, the individual elements must be secured with tension straps. The box also has the standard 35 mm flange on the bottom for stand operation.

A special feature, especially in this price range, is the three-band tone control, which is recessed on the back of the box. Two shelving filters at 80 Hz and 12 kHz, as well as a semi-parametric mid-band with a selectable frequency between 100 Hz and 8 kHz, ensure post-processing of the applied signal. If necessary, the equalizer can also be deactivated using a pressure switch.


Regarding the connection panel, the user has to make do with a single XLR socket, which he can loop through via another XLR socket if necessary. That's it, there's nothing more, but let's be honest, Speakon is eliminated and jack or even Cinch in the performance class? Go away....

Finally, the master volume controller, a power plug and the on/off switch are all located slightly inwards on the back of the housing. Oh, by the way, you can also easily connect a microphone directly. Despite the lack of a gain control, the result is quite usable. Barkers of all countries, unite ;-)



Practice

As soon as you activate the construction, several typical Mackie components catch your eye and ear. In addition to the characteristic blue LED on the front panel, it is the rather soft treble that runs through the entire Mackie speaker range, especially since the treble control is very tasteful.

In general, the sound control is pleasing. Even if the filters in this price range do not quite reach the culture of the more expensive Mackie consoles, the possibility of frequency correction can almost be viewed as a luxury in this segment. With the necessary sensitivity, spatial problem areas can be addressed and possibly sound-unfavorable source material can be processed. So everything is fine?

Well, where there is a lot of light, there is sometimes a bit of shadow. The weight advantages mentioned at the beginning are undoubtedly a relief for your back and your wallet, but they also have the disadvantage that, due to the reduced mass, low-frequency components easily cause the housing to vibrate. Depending on the sound material, you could notice that, especially with strong bass-heavy material and boosting of the same, the housing tends to make a slight drone and the quality of the radiation characteristics of the construction is somewhat reduced.

The fact that a 15-inch model can of course process more low-frequency components than the more commonly used 12-inch model also contributes to this. So, especially to the gentlemen DJ, be careful with the bass control, even if the loudspeaker seduces you.

As expected, there is a slight dip in the high-mid range, as the bass loudspeaker cannot manage the range between 2 - 3 kHz quite as well due to its sluggish mass until the high-frequency horn finally kicks in. I see real problems in this regard. but not because the Hochtorn horn in this design is very expansive and compensates for this small flaw well.

A small annoyance, as with many speakers of the same design, is the cable routing when using the product as a floor monitor. No matter which side the box is on, either the IEC plug or the XLR cable will be bent at an angle, which in the medium term can lead to a cable break or damage to the socket. Therefore, slightly rework the connector arrangement or housing shape and everything is in order. Oh yes, the controls are a bit wobbly because they are not countered on the outer plate. Not existential, but it would have been nice.


Conclusion

It happened as it had to, the active Mackie TH-15A construction is also a really valuable purchase in terms of price-performance ratio. For less than 300 euros you get a highly flexible sound system construction that covers a wide range of areas.

An additional tone control, good workmanship and a very low weight make the TH-15A an all-purpose weapon when it comes to being quick, light, uncomplicated and inexpensive.

Recommended!

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Additional Informations:

Multi-way loudspeaker systems featuring a 1-inch compression driver and a 15-inch woofer have become a cornerstone in the professional audio (PA) industry. These systems are designed to deliver high-fidelity sound across a wide frequency range, combining the strengths of both high-frequency precision and robust low-frequency performance. This article explores the history, technological advancements, and impact of these versatile loudspeaker systems in the PA domain.

### Early Loudspeaker Technology

The origins of loudspeaker technology date back to the early 20th century. Initial designs were rudimentary and typically featured a single driver attempting to cover the entire audio spectrum. These early systems, often horn-loaded to improve efficiency, were limited in frequency response and sound fidelity. The single driver struggled to reproduce both low and high frequencies accurately, resulting in significant audio distortion and subpar performance.

### Emergence of Multi-Way Systems

The need for improved sound quality led to the development of multi-way loudspeaker systems. By using multiple drivers, each optimized for a specific portion of the audio spectrum, engineers could enhance sound clarity and minimize distortion. This concept laid the foundation for the multi-way systems that would later feature the combination of a 1-inch compression driver and a 15-inch woofer.

### Introduction of the 1-Inch Compression Driver

Compression drivers are specialized high-frequency drivers designed to produce clear and powerful high-end sound. The 1-inch compression driver, in particular, became popular due to its ability to deliver precise and articulate high frequencies. These drivers use a small diaphragm attached to a voice coil, which is driven by a powerful magnet. The diaphragm's movement compresses the air in a small chamber, which is then directed through a horn to amplify the sound.

#### Early Compression Drivers

The first compression drivers emerged in the 1930s and 1940s, primarily used in public address systems and cinema sound. These early models were relatively crude but laid the groundwork for more advanced designs. The introduction of the 1-inch compression driver marked a significant improvement in high-frequency reproduction, offering better clarity and higher output levels compared to previous technologies.

### Development of the 15-Inch Woofer

Simultaneously, advancements were being made in low-frequency driver technology. The 15-inch woofer became a popular choice for handling bass frequencies due to its ability to move a large volume of air. This driver size struck a balance between low-frequency extension and efficiency, making it ideal for PA applications.

#### Early 15-Inch Woofers

The first 15-inch woofers appeared in the 1950s and 1960s. These early woofers were typically used in large speaker cabinets and were designed to provide powerful bass response for live music and public address systems. Over time, improvements in materials and engineering led to more efficient and robust woofer designs.

### Birth of the 1/15 Multi-Way Loudspeaker System

Combining the strengths of the 1-inch compression driver and the 15-inch woofer, the 1/15 multi-way loudspeaker system emerged as a powerful solution for PA applications. These systems typically feature a two-way design, with the 15-inch woofer handling low and mid frequencies and the 1-inch compression driver covering the high frequencies.

#### Early 1/15 Systems

The first 1/15 multi-way systems appeared in the 1960s and 1970s. These systems used passive crossovers to divide the audio signal into separate frequency bands, directing each band to the appropriate driver. The passive crossover networks were relatively simple, consisting of capacitors, inductors, and resistors, but they marked a significant improvement in sound quality compared to single-driver designs.

### Advances in Crossover Technology

Crossover technology quickly became a focal point for innovation in multi-way loudspeaker systems. Early passive crossovers had fixed crossover points, limiting their flexibility and performance. As technology advanced, more sophisticated crossover designs were developed, allowing for adjustable crossover points and improved frequency band separation.

#### Active Crossovers

The introduction of active crossovers in the 1970s and 1980s revolutionized the design of 1/15 systems. Unlike passive crossovers, active crossovers are placed before the power amplification stage and use active electronic components like transistors and operational amplifiers. This placement allows for more precise control over the frequency division and offers the ability to adjust crossover points more accurately. Active crossovers also enable independent amplification for each driver, improving overall system efficiency and sound quality.

### Driver Technology and Materials

The evolution of driver technology and materials has been integral to the development of 1/15 multi-way loudspeaker systems. Early drivers used paper cones and metal diaphragms, which had limitations in terms of durability and sound fidelity. Over time, new materials such as polypropylene, Kevlar, and carbon fiber were introduced, offering improved performance characteristics.

#### Woofer Development

Woofers in 1/15 systems are designed to handle low and mid frequencies, typically ranging from 20 Hz to 1.5 kHz. Advances in woofer design have focused on improving cone materials, motor structures, and suspension systems to enhance low-frequency response and minimize distortion. Modern woofers often use materials like treated paper, aluminum, or composite materials to achieve the desired balance of strength and lightness.

#### Compression Driver Development

Compression drivers, particularly the 1-inch variety, are responsible for high frequencies, usually from 1.5 kHz to 20 kHz. The development of new diaphragm materials such as titanium and mylar, along with improvements in magnet structures and phase plug designs, has significantly enhanced the performance of these drivers. Modern 1-inch compression drivers offer higher output, greater clarity, and improved reliability compared to their predecessors.

### Integration with Digital Signal Processing (DSP)

The advent of digital signal processing (DSP) in the late 20th century brought about another wave of innovation in 1/15 multi-way loudspeaker systems. DSP allows for precise control over various aspects of the audio signal, including equalization, crossover settings, and time alignment. This technology enables engineers to optimize the performance of 1/15 systems in real-time, compensating for acoustic anomalies and ensuring consistent sound quality across different environments.

### Applications in Professional Audio

1/15 multi-way loudspeaker systems are ubiquitous in professional audio applications due to their balance of performance, cost, and complexity. They are commonly used in live sound reinforcement, installed sound systems, and studio monitoring.

#### Live Sound Reinforcement

In live sound applications, 1/15 systems offer the clarity and power needed to deliver high-quality audio to audiences of various sizes. They are often used in combination with subwoofers to extend the low-frequency response, creating a full-range sound system capable of handling a wide variety of music and speech content.

#### Installed Sound Systems

1/15 loudspeakers are also prevalent in installed sound systems, such as those found in theaters, stadiums, and houses of worship. Their ability to provide even coverage and high intelligibility makes them ideal for these environments, where both music and speech reproduction are critical.

#### Studio Monitoring

In the studio, 1/15 monitors are essential tools for recording and mixing engineers. They provide accurate sound reproduction, allowing engineers to make precise adjustments to their recordings. The combination of a 15-inch woofer and a 1-inch compression driver ensures that these monitors can handle a wide range of frequencies, providing a clear and detailed sound.

### Conclusion

The evolution of 1/15 multi-way loudspeaker systems has been marked by continuous innovation and improvement. From their early beginnings as a solution to the limitations of single-driver designs, these systems have evolved into highly sophisticated and versatile tools in the professional audio industry. Advances in crossover technology, driver materials, and digital signal processing have all contributed to the superior performance and widespread adoption of 1/15 systems. As technology continues to advance, the future of 1/15 loudspeaker systems promises even greater enhancements, further solidifying their role as indispensable components in the world of professional audio.

TEST: Mackie TH-12A

 If you have dealt with the topic of active 2-way sound reinforcement in recent years, you cannot avoid the name Mackie. Especially when it comes to lightweight construction combined with uncomplicated handling, the name comes up again and again. With the Thumb series, in addition to the successful TH-15A, Mackie now also relies on the smaller version TH-12A, which, as expected, comes with the more compact 12-inch version instead of a 15-inch woofer, without reducing the performance specifications.

The construction was designed by the same guild that produced the best-selling SRM450v2. The product was developed in the USA and the active box is built in China.


construction

The Mackie TH-12A is an active two-way speaker, which has a power output of 200 watts sine wave and a peak of 400 watts, with the 12 inch bass speaker having a 150 watt Class D, and the 1 inch tweeter driver a Class AB power amplifier is operated. As is usual in this performance class, the construction is designed as a bass reflex. The woofer is protected from external influences by a solid metal grille, and the driver is installed sufficiently back.

As with its big sister, the very light casing made of polypropylene ensures that the product only has a very moderate total weight of 11.6 kilograms despite generously proportioned performance specifications and casing dimensions of 596 x 367 x 314 mm. Despite the pure plastic design, the housing proves to be scratch-resistant and "deformable", which means that the plastic tray does not break easily under strong mechanical external influences.

Thanks to its trapezoidal shape, the design can be used from the classic vocal system to the floor monitor area to a simple small P.A. expand if you generate a corresponding daisy chain operation of several components and do not need the ultimate sub-bass in your performance. It gives the impression that speech and song transmission in the P.A. Area is the primary area of application of the box.


In order to be able to move the construction at the most ergonomic angle at any time, the product has three handles or recessed grips, two on the outside and one on the top. This means that the box can be maneuvered relatively easily onto a high stand without putting excessive strain on the back area. The construction only has four stacking troughs on the underside, which defines the area of application of the construction even more precisely. The Tower of Babel is not the thing here, but rather the department of additional subwoofers plus a spacer rod. To ensure this operating mode, the box has the standard 35 mm flange on the bottom for stand operation.

The integrated three-band tone control, which is recessed on the back of the box for protection reasons, is always a real plus. Two shelving filters at 80 Hz and 12 kHz, as well as a semi-parametric midband with a selectable frequency between 100 Hz and 8 kHz, ensure post-processing of the applied signal if necessary. If in doubt, the equalizer can also be deactivated using a pressure switch.


As with the TH-15A, the user has to make do with a single XLR socket, which he can loop through via another XLR socket if necessary. A cinch plug might be helpful for connecting an MP3 player or similar equipment; if necessary, you can of course also work with adapters.


Finally, the master volume control, a power plug and the on/off switch, as well as the tone control controls, are all located slightly inwards on the back of the housing. Due to the XLR input, you can also connect a microphone directly if necessary. Due to the lack of a gain control, there may be a slight mismatch, but the basic function will be retained.


Practice

If you apply a signal to the speaker, you will immediately hear the characteristic Mackie sound. The fairly soft highs and the open sound ensure a universal area of use. Once again, the treble control at 12 Khz is particularly pleasing, an area that tends to cause unpleasant scratching in the competition. Even if the sound culture does not reach the range of the VLZ series, the filter section is very appealing for this price segment.

With the necessary sensitivity, spatial problems can be put into perspective with the help of the parametric mid control or source material that is sonically unfavorable can be processed. Remember, to get sound problems under control, you can also lower frequencies! The midrange in particular sometimes prefers the minus dB range rather than the boost sector. At 80 Hz, the bass control is relatively low for a 12-inch speaker, but it works pleasantly discreetly so that, assuming moderate handling, you don't have to worry about a low output.

Due to the 12-inch device, a fact that should not be underestimated can be easily identified. While the large TH-15A version has a slight dip in the high-mid range, as the bass loudspeaker does not quite keep in touch with the tweeter horn in the range between 2 - 3 kHz due to its inert mass, the faster 12 inch version gets out of the starting blocks much faster and conveys a more homogeneous sound spectrum.

What is pleasantly noticeable about this design is the cable routing when using the product as a floor monitor. While the big sister still had problems with plugs bending, especially with the power cables, due to the shape, the TH-12A has thought better of it. For the first time, regular Neutrik plugs can be used without there being any mechanical stress on the quick-release axles, but only if the box with the tweeter horn is on the left side. What remains are the somewhat wobbly controls, which are not countered on the outer panel. Not really bad, but it would have been an additional security point.



Conclusion

With the active TH-12A construction, Mackie is expanding its position in the active 2-way sector and leaves a good overall impression. For just under €300 street price you get an easy-to-use, flexible sound system construction that serves a wide range of applications.

Small, light, well-engineered and with good workmanship, you can't go wrong with this product. Anyone thinking about purchasing in this segment should have the TH-12A on their list.

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Additional Informations:

Two-way loudspeaker systems are a cornerstone of professional audio (PA), celebrated for their ability to deliver a broad frequency range with clarity and efficiency. By dividing audio signals into two frequency bands, each handled by specialized drivers, two-way systems offer a balance between performance and complexity, making them a popular choice in various PA applications. This article delves into the rich history and development of two-way loudspeaker systems, tracing their technological advancements and impact on the audio industry.

### Early Loudspeaker Designs

The origins of loudspeaker technology date back to the early 20th century. Initial designs were rudimentary, often consisting of a single driver tasked with reproducing the entire audio spectrum. These early systems, frequently horn-loaded to boost efficiency, struggled with limitations in frequency response and sound fidelity. The single driver could not effectively cover both low and high frequencies, resulting in significant audio distortion and subpar performance.

### The Concept of Multi-Way Systems

The quest for improved sound quality led to the concept of multi-way loudspeaker systems. By using multiple drivers, each optimized for a specific portion of the audio spectrum, engineers could enhance sound clarity and minimize distortion. This concept laid the foundation for the development of two-way loudspeaker systems, which became the first step towards more sophisticated multi-way designs.

### Birth of the Two-Way System

The two-way loudspeaker system emerged as a solution to the limitations of single-driver designs. It typically consists of a woofer, responsible for low frequencies, and a tweeter, designed for high frequencies. The key innovation in two-way systems is the crossover network, which divides the audio signal into separate frequency bands, directing each band to the appropriate driver.

#### Early Two-Way Designs

The first two-way loudspeaker systems appeared in the 1930s and 1940s. These early models used passive crossovers, which are placed between the amplifier and the drivers. Passive crossovers rely on passive electronic components like capacitors, inductors, and resistors to split the audio signal. These components were relatively simple but marked a significant improvement over single-driver systems, offering better sound quality and higher output levels.

### Advancements in Crossover Technology

Crossover technology quickly became a focal point for innovation in two-way loudspeaker systems. Early passive crossovers had fixed crossover points, which sometimes limited their flexibility and performance. As technology advanced, more sophisticated crossover designs were developed, allowing for adjustable crossover points and improved frequency band separation.

#### Active Crossovers

The introduction of active crossovers in the 1960s and 1970s revolutionized the design of two-way systems. Unlike passive crossovers, active crossovers are placed before the power amplification stage and use active electronic components like transistors and operational amplifiers. This placement allows for more precise control over the frequency division and offers the ability to adjust crossover points more accurately. Active crossovers also enable independent amplification for each driver, improving overall system efficiency and sound quality.

### Driver Technology and Materials

The evolution of driver technology and materials has been integral to the development of two-way loudspeaker systems. Early drivers used paper cones, which, while lightweight and efficient, had limitations in terms of durability and sound fidelity. Over time, new materials such as polypropylene, Kevlar, and carbon fiber were introduced, offering improved performance characteristics.

#### Woofer Development

Woofers in two-way systems are designed to handle low frequencies, typically ranging from 20 Hz to 2 kHz. Advances in woofer design have focused on improving cone materials, motor structures, and suspension systems to enhance low-frequency response and minimize distortion. Modern woofers often use materials like treated paper, aluminum, or composite materials to achieve the desired balance of strength and lightness.

#### Tweeter Development

Tweeters are responsible for high frequencies, usually from 2 kHz to 20 kHz. The development of dome tweeters in the mid-20th century represented a significant leap forward. Dome tweeters, with their lightweight diaphragms and efficient motor structures, offer superior high-frequency response and dispersion compared to earlier cone tweeters. Materials such as silk, aluminum, and titanium are commonly used in modern tweeter designs to achieve the desired performance.

### Integration with Digital Signal Processing (DSP)

The advent of digital signal processing (DSP) in the late 20th century brought about another wave of innovation in two-way loudspeaker systems. DSP allows for precise control over various aspects of the audio signal, including equalization, crossover settings, and time alignment. This technology enables engineers to optimize the performance of two-way systems in real-time, compensating for acoustic anomalies and ensuring consistent sound quality across different environments.

### Applications in Professional Audio

Two-way loudspeaker systems are ubiquitous in professional audio applications due to their balance of performance, cost, and complexity. They are commonly used in live sound reinforcement, installed sound systems, and studio monitoring.

#### Live Sound Reinforcement

In live sound applications, two-way systems offer the clarity and power needed to deliver high-quality audio to audiences of various sizes. They are often used in combination with subwoofers to extend the low-frequency response, creating a full-range sound system capable of handling a wide variety of music and speech content.

#### Installed Sound Systems

Two-way loudspeakers are also prevalent in installed sound systems, such as those found in theaters, stadiums, and houses of worship. Their ability to provide even coverage and high intelligibility makes them ideal for these environments, where both music and speech reproduction are critical.

#### Studio Monitoring

In the studio, two-way monitors are essential tools for recording and mixing engineers. They provide accurate sound reproduction, allowing engineers to make precise adjustments to their recordings. The compact size and high performance of two-way monitors make them a popular choice in both professional and home studios.

### Conclusion

The evolution of two-way loudspeaker systems has been marked by continuous innovation and improvement. From their early beginnings as a solution to the limitations of single-driver designs, two-way systems have evolved into highly sophisticated and versatile tools in the professional audio industry. Advances in crossover technology, driver materials, and digital signal processing have all contributed to the superior performance and widespread adoption of two-way systems. As technology continues to advance, the future of two-way loudspeaker systems promises even greater enhancements, further solidifying their role as indispensable components in the world of professional audio.

TEST: Mackie SRM450V2

 In recent years there has been a trend in the sound reinforcement industry that relies on minimal housing dimensions with maximum power output. We're talking about powerful active speakers, which, due to their compact design, have recently been increasingly found at smaller club gigs, small open air sound systems and increasingly with cover bands of various styles. A typical representative of this genre is the SRM450v2 from the American manufacturer Mackie, a box which, due to its asymmetrical trapezoidal shape, can handle both PA sound reinforcement and be used as a floor wedge.

Construction:

The loudspeaker system is a relatively clear plastic construction with the dimensions: height 66 centimeters, width 39 centimeters, depth 38 centimeters, and weighs 18 kilograms. The coarse-grained plastic housing makes a highly solid impression and is flawlessly processed. Due to the carrying handles, which are both ergonomically positioned and ensure a good grip thanks to their core, the SRM450 can be easily moved to the appropriate high stand as well as to the wedge position.

In order to lock the box on the stand, there is an additional screw connection on the bottom/back of the construction. If the system is to be operated as a flying structure, a total of eight different rigging points are available to the user. Due to a recessed recess on the top of the housing, the box can be easily transported with one hand. For stacking purposes, there are 3 feet or troughs embedded on the top and bottom, which are further secured against involuntary movement using external bolts.

The SRM450v2 is an active biamping system, which consists of a titanium tweeter horn with a load capacity of 100 watts and a 15 inch woofer speaker with a load of 300 watts. From a sound pressure of approx. 120 db, a compressor regulates the power in the soft knee setting; the use of the compressor is indicated by an LED on the back. In collaboration with additional subwoofers, two SRMv2s can be turned into a small P.A. in no time. put together, which also accounts for ambitious club sound systems. It should be noted that the boxes are not suitable for unconditional outdoor use. When used in public, the components must be protected from rainwater or moisture.

The horizontal radiation is given as 90 degrees; for the vertical radiation, the tweeter horn is assigned a radiation of 45 degrees. Mackie points out that the usual problem of selective radiation at high frequencies is eliminated with her tweeter horn.   The tweeter horn is recessed approx. 15 centimeters into the housing to protect it from damage during transport. A relatively finely perforated, black steel grille, which was secured with four screws, is used to protect the woofer installed on the rear.

The amplifier unit is located on the back of the box. The central power switch is located next to the cold appliance power socket. The only input connectors are limited to a female and a male XLR connector. You can cascade several systems by connecting the XLR connectors in parallel. This has the advantage that you can initially start with a single pair of speakers and then adapt to the sound requirements by purchasing additional systems. Additional passive speakers cannot be connected to the amplifier unit; the speaker unit works autonomously, so to speak.

Using an automatically controlled “Timed Turnoff” switch, the box switches off automatically below a minimum input level. When it comes to sound control, the low frequencies below 100 Hertz and the high frequencies above 12 kilohertz can be increased by three dB. A low-cut switch lowers the frequencies below 75 Hertz if necessary. Especially for wedge use, you should lower the low bass range; anything in the double-digit range has no place in a floor monitor. A simple input controller is used to determine the input sensitivity for the signal applied. In an emergency, dynamic microphones can also be connected directly due to the gain of up to +40 dB, but these then only have a rudimentary sound control. The interposition of a regular mixer is definitely the better option, but it is nice to know that you can do without this intermediary in an emergency. 22 massive black cooling fins ensure sufficient cooling of the unit.


Practice:

When you press the power switch, a bright blue LED on the front of the device reports the operating status. A switch-on limitation prevents any form of switch-on impulse, so this process takes place absolutely noiselessly. While the woofer operates with absolutely no background noise when in idle mode, there is a quiet humming noise coming from the tweeter horn, which shouldn't be noticeable even at quiet events. In addition, with a pre-amplification of over + 30 db, a slight noise occurs, which, however, will be below the audible limit at the expected volume.

What distinguishes the SRM450v2 from the first sound impression is a very vivid reproduction with a high degree of depth. In contrast to many other vocal systems, which are sometimes unpleasant due to their very tight or harsh reproduction of the signal, the Mackie Box has a kind of “velvety sound” across the entire frequency range. The high-mid range in particular is particularly pleasing thanks to its precise location in the stereo image. If you as an audience have the pleasure of staying within the stereo triangle, you can actually enjoy a spatial stereo image, a fact that is usually lost in the sound system of small events. Here you are more than happy if you can offer the listener audiophile accessibility so that they can actually hear the signal; stereo images are sometimes considered pure luxury here.

The tweeter's radiation behavior as described by Mackie is also not exaggerated; even with a spatial offset of 45 degrees, the listener can still clearly perceive the high-frequency range, which makes it possible to set it up even in difficult terrain. The bass reflex openings on the right and left below the woofer ensure powerful bass. Roaring frequencies via standing waves or housing vibrations could not be heard.



Conclusion:

With the SRM450v2, the traditional American manufacturer of mixing consoles presents a more than solid workhorse that is truly impressive with its performance features. Especially when things have to be done quickly and every meter of cable that needs to be laid is too much, the box can show its strengths.

In terms of price, it's absolutely within the green range, so it's a good idea to buy a small park of SRM450 systems and, depending on the size, use the speakers as stand-alones, in cascade connection or as individual wedges.

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Additional Informations:

Multi-way loudspeaker systems, commonly referred to as multi-way speakers, are essential components in professional audio (PA) setups. These systems are designed to reproduce sound across a wide frequency range by dividing the audio signal into multiple frequency bands, each handled by specialized drivers. The development of multi-way speakers has been a significant milestone in audio engineering, improving sound quality, coverage, and efficiency in various applications from live concerts to public announcements.

### Early Loudspeaker Systems

The roots of modern loudspeaker technology can be traced back to the early 20th century. The first loudspeakers were relatively simple devices, typically consisting of a single driver responsible for covering the entire audio spectrum. These early designs, often horn-loaded for improved efficiency, were limited in their frequency response and sound quality. The single driver struggled to accurately reproduce both low and high frequencies, leading to distortion and poor audio performance.

### Birth of Multi-Way Systems

The limitations of single-driver systems led to the development of multi-way loudspeakers. The basic principle behind multi-way systems is to use multiple drivers, each optimized for a specific portion of the audio spectrum. This approach minimizes distortion and improves clarity by ensuring that each driver operates within its optimal frequency range.

#### Two-Way Systems

The first multi-way systems were two-way designs, featuring a woofer for low frequencies and a tweeter for high frequencies. The introduction of crossovers—electronic circuits that divide the audio signal into separate frequency bands—was a critical innovation. Passive crossovers, which are placed between the amplifier and the drivers, became standard in these early designs. Two-way systems offered significant improvements over their single-driver predecessors, providing better sound quality and higher output levels.

### Advancements in Crossover Technology

As the demand for higher fidelity and more powerful PA systems grew, so did the complexity of crossover networks. Engineers began experimenting with different crossover designs, including active crossovers, which are placed before the power amplification stage. Active crossovers allow for greater precision in frequency band division and offer adjustable crossover points, enabling fine-tuning of the system for specific applications.

### Three-Way and Beyond

The evolution continued with the introduction of three-way systems, which added a midrange driver to handle the frequencies between the woofer and tweeter. This further enhanced the clarity and detail of the sound, as each driver could now operate within an even narrower frequency range. The three-way design became popular in high-end PA systems, providing a more balanced and dynamic sound.

Further advancements led to the development of four-way and even five-way systems, incorporating additional drivers such as subwoofers for ultra-low frequencies and super-tweeters for ultra-high frequencies. These complex systems required sophisticated crossover designs and precise engineering to ensure seamless integration between drivers.

### The Role of Materials and Driver Technology

The evolution of multi-way loudspeaker systems has also been driven by advancements in materials and driver technology. Early loudspeaker cones were typically made of paper, which, while lightweight, had limitations in terms of durability and sound quality. Modern drivers use advanced materials such as Kevlar, carbon fiber, and various composites, which offer superior performance characteristics.

The development of new magnet materials, such as neodymium, has allowed for more powerful and efficient drivers. Neodymium magnets are significantly stronger than traditional ferrite magnets, enabling the design of compact yet powerful drivers that are ideal for multi-way systems.

### Integration with Digital Signal Processing (DSP)

The integration of digital signal processing (DSP) has revolutionized multi-way loudspeaker systems in recent years. DSP allows for precise control over every aspect of the audio signal, including crossover points, equalization, and time alignment. This technology enables engineers to optimize the performance of multi-way systems in real-time, compensating for acoustic anomalies and ensuring consistent sound quality across different environments.

### Applications in Professional Audio

Multi-way loudspeaker systems are ubiquitous in professional audio applications. In live sound reinforcement, they provide the clarity and power needed to deliver high-quality audio to large audiences. Line array systems, which consist of multiple multi-way speaker cabinets stacked vertically, have become standard in concert sound, offering excellent coverage and sound pressure levels.

In installed sound systems, such as those found in theaters, stadiums, and houses of worship, multi-way speakers ensure even coverage and intelligibility, critical for both music and speech. Studio monitors, another application of multi-way systems, provide the accurate sound reproduction needed for recording and mixing music.

### Conclusion

The evolution of multi-way loudspeaker systems has been driven by the quest for better sound quality, higher efficiency, and greater versatility in professional audio applications. From the early days of rudimentary single-driver speakers to today's sophisticated multi-way systems with advanced materials and digital processing, the journey has been marked by continuous innovation and improvement. As technology continues to advance, the future of multi-way loudspeaker systems promises even greater enhancements, further solidifying their role as indispensable tools in the world of professional audio.

TEST: Mackie SRM350V2

 Never change a winning team or you can expand your product range. OK, the comparison seems a bit brittle, but the product developers at Mackie must have felt something similar when it came to the SRM series.

Similar to the instrument amplifier sector, there are relatively identical concepts here, which only vary upwards or downwards depending on the type in terms of speaker configuration or power output. For example, the SRM350v2 active box I was testing has its sister model SRM450v2, a product that was supposed to do very well in one of the last tests.

With the 350 version, the priorities have now been placed on better transportability and the product has been significantly reduced in terms of dimensions. Let's see to what extent the little brother can keep up in terms of sound, workmanship and practicality.


Construction:

The SRM350v2 once again uses polypropylene as a construction material, a robust material that has the right mix of hardness (stable construction) and softness (risk of breakage in the event of strong impacts). The dimensions of the construction are height 53 centimeters, width 34 centimeters, depth 31 centimeters, with a weight of 12 kilograms, ensuring that the box can also be easily transported in a small car.

The shape of the box is an asymmetrical trapezoid, which means the box can be used as a stand-alone or satellite solution for P.A., sidefill or as an approx. 45 degree wedge.

A carrying handle on the side of the housing, equipped with an ergonomically placed core, ensures that the box can be easily lifted onto a high stand. A corresponding flange is attached to the underside of the housing.

In general, the box can be described as very handy, as its center of gravity when approached on this handle can be described as very successful. Thanks to an additional recessed grip on the top of the housing, the box can also be quickly maneuvered vertically. 4 strong plastic feet secure the construction against slipping, but there are no recesses on the top for stacking.

You can see that the SRM350v2 can be flown, and appropriate screws can be attached to the top, but the primary focus is on small standing operations. Compared to the 8 rigging points of the 450 version, the 350 has focused on the essentials.



The SRM350v2 is an active biamping system, which consists of a 1.4 inch titanium tweeter horn with a load capacity of 75 watts and a 10 inch woofer speaker with a load of 250 watts. The speakers are powered by a Class D 165 watt woofer amplifier and a 30 watt Class AB tweeter amplifier.

The woofer amplifier is factory-equipped with a dynamic bass boost, which ensures that the frequencies below 70 Hertz are reduced as the volume increases. This not only ensures that the power-consuming frequencies in the high-load range absorb the lion's share of the power, but it also takes into account the fact that the human ear reacts more sensitively to the low-frequency range at high volumes.

At maximum volume, a limiter regulates the power in the soft knee setting at the first distortion; the use of the limiter is indicated by an LED on the back. In collaboration with additional subwoofers, two SRMv2s can be turned into a small P.A. in no time. put together, which also accounts for small club sound systems. It should be noted that the boxes are not suitable for unconditional outdoor use. When used in public, the components must be protected from rainwater or moisture.

The horizontal radiation is given as 90 degrees. The tweeter horn is recessed approx. 10 centimeters into the housing to protect it from damage during transport. A relatively finely perforated, black steel grille, which was secured with four screws, is used to protect the woofer installed on the rear.

The amplifier unit is located on the back of the box. The central power switch is located next to the cold appliance power socket. The input plug is the well-known variant of an XLR female and a 6.35 jack plug, both of which can be locked.

Using a switch, the input sensitivity can be switched between microphone and line level. A simple input controller is used to determine the input sensitivity for the signal applied. Due to the gain of up to +40 db (microphone) or + 5 db (line), dynamic microphones can also be connected directly.

Phantom power is not provided, which means condenser microphones must be operated with an internal battery. When it comes to sound control, the low frequencies below 100 Hertz and the high frequencies above 12 kilohertz can be increased by three dB using a contour switch.

There is an XLR male above the input plug for daisy chain cascading. Additional passive speakers cannot be connected to the amplifier unit. 19 massive black cooling fins ensure sufficient cooling of the unit.


Practice:

When you press the power switch, a bright blue LED on the front of the device reports the operating status. In general, the SRM350v2 can be said to have the same sound attributes as its big 450 sister. Here too you will encounter a soft, three-dimensional reproduction with the “velvety” sound already mentioned. Despite the lack of internal damping, the plastic housing has no resonance frequencies or standing waves.

The spatial reproduction can be described as successful, although of course you always have to take the acoustic conditions of the area of use into account. Due to the good radiation behavior of the tweeter unit, speech intelligibility remains unusually good even with unfavorable reflections and ensures that everyone's faces are happy.

In addition, the box sounds very pleasant even at low volumes; the voice coils do not require a large stroke as with other products to get a voluminous sound from the speakers.

The only criticism of the design is the fact that an angled power plug should be used when operating as a floor monitor, as a straight plug would be bent relatively sharply due to the angle and positioning of the socket.



Conclusion:

As with its big sister, the SRM450v2, the smaller 350 version ensures a harmonious and all-round successful appearance. For use in moderate volume operation, you will find a handy partner that is unobtrusive, can be set up and ready for use in a very short time, with just a few simple steps and extremely clear cable requirements.

Tons of dance and cover bands will appreciate exactly these features, plus you can start with a couple and then upgrade as needed, both in the monitor and in the P.A. Area.

A coherent system with high practical suitability.

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Additional Informations:

## The History of Multi-way Loudspeakers in the P.A. Industry

Multi-way loudspeakers have become a staple in the P.A. industry, providing superior sound quality and versatility compared to traditional full-range speakers. Their ability to reproduce a wide range of frequencies with clarity and detail has made them essential for a variety of applications, from live concerts and theatrical performances to houses of worship and corporate events.

The history of multi-way loudspeakers can be traced back to the early days of sound reinforcement, when engineers began experimenting with dividing the audio spectrum into different frequency bands and reproducing each band with a dedicated driver. This approach offered several advantages over full-range speakers, which were often limited in their ability to reproduce both high and low frequencies accurately.

One of the pioneers of multi-way loudspeaker design was Paul Klipsch, who founded the Klipsch company in 1946. Klipsch was a firm believer in the benefits of multi-way design, and he developed a number of innovative loudspeaker systems that helped to popularize the technology.

In the 1960s and 1970s, multi-way loudspeakers continued to evolve, as engineers developed new materials and techniques for driver design. This led to the development of more efficient and powerful loudspeakers that could handle a wider range of frequencies.

The 1980s saw the introduction of a number of new technologies that further improved the performance of multi-way loudspeakers. These included the use of computer-aided design (CAD) software to optimize driver design, the development of new materials such as titanium and kevlar, and the use of advanced crossover networks to divide the audio spectrum more precisely.

Today, multi-way loudspeakers are available in a wide variety of configurations, from simple two-way systems to complex line arrays with dozens of drivers. They are used in a wide range of applications, from small clubs and bars to large stadiums and arenas.

Here are some of the key milestones in the history of multi-way loudspeakers:

* **1946:** Paul Klipsch founds the Klipsch company and begins developing multi-way loudspeaker systems.
* **1960s and 1970s:** New materials and techniques for driver design lead to more efficient and powerful multi-way loudspeakers.
* **1980s:** Introduction of CAD software, new materials, and advanced crossover networks further improves the performance of multi-way loudspeakers.
* **Today:** Multi-way loudspeakers are available in a wide variety of configurations and are used in a wide range of applications.

Multi-way loudspeakers have played a significant role in the evolution of sound reinforcement. Their superior sound quality and versatility have made them an essential tool for sound engineers and musicians alike. As technology continues to advance, we can expect to see even more innovative and powerful multi-way loudspeakers in the years to come.

## Paul Klipsch and the Pioneering Spirit of Multi-way Loudspeakers

Paul W. Klipsch, a renowned American audio engineer and founder of the Klipsch company, stands as a pivotal figure in the development of multi-way loudspeaker systems. His innovative designs and unwavering belief in the benefits of separating the audio spectrum played a crucial role in shaping the P.A. industry and the way we experience sound today.

**Early Inspiration and the Klipsch Horn:**

Klipsch's fascination with acoustics began during his studies at the University of Arkansas, where he conducted research on horns for phonographs. He recognized the limitations of traditional full-range speakers, particularly their struggles with reproducing both high and low frequencies efficiently. Inspired by the natural amplification properties of horns, Klipsch began experimenting with horn designs that could improve speaker performance.

**The Klipschorn: A Cornerstone of Multi-way Design:**

In 1936, Klipsch unveiled his revolutionary creation - the Klipschorn. This horn-loaded loudspeaker system represented a significant leap forward in loudspeaker technology. The Klipschorn utilized a folded bass horn design to efficiently reproduce low frequencies. This freed up the other drivers in the system to focus on reproducing midrange and high frequencies with greater clarity and detail. It wasn't just a two-way system though.  The Klipschorn incorporated a tweeter and a squawker (midrange driver) alongside the bass horn, effectively creating a three-way design. This approach not only improved sound quality but also allowed for increased efficiency, meaning the Klipschorn could produce louder sound with lower amplifier power compared to traditional full-range speakers.

**Beyond the Klipschorn:**

The success of the Klipschorn solidified Klipsch's reputation as a pioneer in loudspeaker design. He continued to refine and develop multi-way concepts, creating new horn designs and exploring different driver configurations. He advocated for the benefits of high efficiency and accurate frequency response, challenging the prevailing industry norms. His work inspired other engineers and companies to explore the potential of multi-way loudspeakers, leading to further advancements in the field.

**Klipsch's Legacy:**

Klipsch's dedication to multi-way loudspeaker technology laid the foundation for the high-fidelity sound reproduction we experience today. His principles of efficient horn design, accurate frequency response, and meticulous crossover networks have become cornerstones of modern loudspeaker construction. While technology and materials have evolved significantly since his time, the core concepts he championed remain relevant. Today, Klipsch continues to be a leading manufacturer of high-performance multi-way loudspeakers for a variety of applications, from home audio to professional sound reinforcement systems.

**Further Exploration:**

Here are some additional points to consider when exploring Klipsch's work with multi-way loudspeakers:

* **The Importance of Crossover Networks:** Klipsch recognized that simply separating the audio spectrum wouldn't be enough. He developed sophisticated crossover networks to ensure each driver received the correct frequencies and prevent overlap between them.
* **The Klipsch Synergy:** Klipsch believed in a holistic approach to loudspeaker design. He emphasized the importance of integrating the drivers, crossover networks, and enclosure design to achieve optimal performance.
* **The Debate Over Horn Design:** Not everyone embraced Klipsch's horn-loaded designs. Some audiophiles argued that horns could introduce coloration to the sound. However, Klipsch constantly improved his designs to minimize this effect.

By delving deeper into these aspects,  you can gain a richer understanding of Paul Klipsch's groundbreaking contributions to the world of multi-way loudspeakers and their lasting impact on the P.A. industry.

TEST: Mackie S408

 In addition to its main area of application, the production of mixing consoles, Mackie has increasingly invested in the area of sound reinforcement in terms of know-how and implementation in recent years. Little by little, without much fanfare, the entire area from the smallest monitor for keyboard players to the medium-sized club P.A. processed. It is not surprising that Mackie quickly gained a foothold in this segment and, like its consoles, was able to gain a good reputation within a short time.

In addition to the increasingly popular area of active speakers, Mackie also serves the classic passive area. A promising candidate from this segment is the S408 I have, a two-way speaker which, due to its asymmetrical trapezoidal shape, can handle both PA sound reinforcement and be used as a floor wedge.

Construction:

The S408 is a component that is already in the P.A. segment is to be classified. Both the load information and the dimensions go beyond the “singing system use” without negating their use in this area.

600 watts RMS and 2400 watts peak speak for themselves, and you also need at least 2 strong men to adequately move the 81 cm high, 51 cm wide and 46 cm deep, along with its 33 kg weight, or balance it on a high stand.

The case of the S408 is made of 18 mm multi-layered plywood and makes a solid and flawlessly manufactured impression. A PVC layer is used as the outer layer to provide moisture resistance.

A total of 3 handles were installed on the S408, one on each side plus a handle on the top of the case. 4 stacking corners ensure a stable hold in the upright position, its side parts are provided with small rubber feet to also prevent it from slipping when used as a wedge. The box has sufficient rigging points to allow the system to be operated sideways or upright if necessary.

The S408 is a passive 2-way system equipped with 5 speakers, which has 2 Speakon sockets (Input / Thru) as the only connections on the back, through which the systems can be cascaded if necessary. In addition to a high-midrange horn separated at 2500 Hertz for the treble range, Mackie relies on 4 8-inch ferrite speakers for the bass range. The acoustic reason is obvious and is similar to the use of 4x10" bass speakers in the instrumental area.

A larger number of smaller loudspeakers have approximately the same membrane area as a single large loudspeaker and can therefore move the same amount of air, but are significantly more faithful to impulses, have a much faster response and the spatial arrangement allows a much more balanced sound to be generated. That's what happened here too. To ensure more even radiation, two 8-inch speakers were installed slightly to the right and left, respectively, above and below the high-midrange horn.

The box is not insulated on the inside and has bass reflex openings on the back both below and above the connection panel. Even if it is generally known that the box should never be placed in the corner of a room, uncontrolled drone frequencies would undoubtedly be the logical consequence, especially with a rear reflex construction as described here.

According to the frequency diagram, the S408 has a fairly even frequency response between 100 Hertz and up to 10 kilohertz, with only a small dip at 500 Hertz and an over-presence at 6 kilohertz being noted. Below or above these marks, the playability drops significantly.

Thanks to the trapezoidal shape (radius 37.5 degrees), you can cover a vertex radius of 75 degrees when using two S408s next to each other, which promotes very good coverage of the auditorium.

Practice:

The S408 can be used in a variety of ways. Due to its neutral orientation, it can be used as a stand-alone solution, as a satellite solution on a subwoofer, as a sidefill or as a wedge.

When you start using it, you immediately notice the radiation behavior of the box. In fact, you can easily move up to 30 degrees away from the center of the box and still have no loss in frequency range. Both the intelligibility of speech transmission and the fidelity of impulses in music are retained.

The second unusual point is the sound of the box in the bass range. What I have known for a long time from the backline in the instrumental area is in the P.A. Area a bit unusual at first. Anyone who has the indirect, always slightly spongy impulse of a 15-inch or even...
Anyone who is used to the flabby 18-inch model, which has a lot of air but has a catastrophic response due to the design, will need a moment to be able to properly assess and appreciate the fast 8-inch model.
The rapid response initially confuses your hearing, but once you get used to the impulse you won't want to part with it. How sluggish your beloved 15 suddenly seems...

Don't misunderstand us, for example, in order to boost a kick at 70 Hertz for the famous "stomach effect", a whole armada of 408s will not be enough; at least a corresponding number of 10" or 12" in the subwoofer must be involved in the sound formation intervention. However, if you are looking for a very powerful satellite solution or a powerful stand-alone solution for small events, you are on the safe side with the S408.

In general, the box is very powerful in the mids, with good speech intelligibility and pleasing vocal reproduction, both from female and male voices. The box does not have a “whitewashing effect”, which means that the “silky” finish that you know from Mackie's active boxes is not present here. On the other hand, the applied signal is processed in a rather “bony” way, but this does not mean that detailed playback is not possible.

All frequencies that are important for the live range are reproduced evenly without any noticeable dips; the deflections recorded by the diagram are absolutely negligible live.

Conclusion:

With its unusual loudspeaker design consisting of a high-midrange horn and four 8-inch bass loudspeakers, the S408 from Mackie takes a path that is not entirely new but rarely used. Wrongfully so, as the test has shown.

The unusually fast impulse fidelity in the bass range and the excellent radiation characteristics make the S408 an all-purpose weapon in the fight against uneven sound reinforcement. The passive two-way system was particularly able to shine in voice transmission, but without disappointing in music reproduction.

If there was one point at all about the S408 that could be criticized, it was the not excessive, but still high weight, which on the one hand supports the impulse fidelity through minimal housing vibrations, but negates the ability to be transported by just one person.

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Additional Informations:

# The Evolution of Multi-Way Loudspeakers in Professional Audio (P.A.) Systems

Multi-way loudspeakers, or speaker systems that use multiple drivers to cover different frequency ranges, are a cornerstone of modern professional audio (P.A.) systems. They provide superior sound quality and power handling compared to single-driver speakers, making them essential for live sound reinforcement, large venues, and public address applications. This article explores the history and development of multi-way loudspeakers in the P.A. domain, highlighting key innovations and technological advancements that have shaped their evolution.

## Early Beginnings: The Birth of Loudspeaker Technology

### The Mono Loudspeaker Era

The development of loudspeakers began in the late 19th and early 20th centuries. The first practical loudspeakers were mono, full-range units that attempted to reproduce the entire audio spectrum using a single driver. These early loudspeakers were rudimentary by today's standards, with limited frequency response and power handling capabilities.

**1920s: The First Electrodynamic Loudspeakers**

The invention of the electrodynamic loudspeaker by Chester W. Rice and Edward W. Kellogg in 1925 marked a significant milestone. This design, which used a voice coil and diaphragm driven by an electromagnet, became the foundation for modern loudspeakers. However, these early speakers still struggled to reproduce the full range of audio frequencies accurately.

### The Advent of Multi-Way Systems

**1930s: The Introduction of Two-Way Systems**

As audio technology progressed, the limitations of single-driver loudspeakers became increasingly apparent. The need for better sound quality, particularly in terms of frequency response and clarity, led to the development of two-way systems in the 1930s. These systems used two separate drivers: a woofer for low frequencies and a tweeter for high frequencies. This division of labor allowed each driver to operate more efficiently within its designated frequency range, resulting in improved overall sound quality.

**1940s: The Emergence of Three-Way Systems**

The 1940s saw the introduction of three-way speaker systems, which added a midrange driver to the woofer and tweeter configuration. This further refined the audio reproduction by dedicating specific drivers to low, mid, and high frequencies, allowing for even greater clarity and accuracy. These advancements were crucial for high-fidelity audio reproduction in both home and professional settings.

## The Rise of Professional Audio Systems

### Post-War Innovations

**1950s: The Birth of P.A. Systems**

The post-World War II era brought about significant advancements in electronic technology and an increasing demand for public address systems. P.A. systems required loudspeakers capable of delivering high sound pressure levels (SPL) over large areas without compromising on sound quality. This need drove further innovation in multi-way speaker design.

**1960s: The Evolution of Sound Reinforcement**

The 1960s marked the beginning of modern sound reinforcement systems. The rise of rock and roll and large-scale concerts necessitated powerful and reliable P.A. systems. Companies like JBL, Altec Lansing, and Electro-Voice began producing robust multi-way loudspeakers specifically designed for live sound applications. These systems often featured horn-loaded designs to increase efficiency and directivity, making them ideal for projecting sound over long distances in large venues.

### The Transition to Modular and Scalable Systems

**1970s: The Advent of Modular P.A. Systems**

The 1970s saw the introduction of modular P.A. systems, which allowed for greater flexibility and scalability. Modular systems consisted of separate components—such as subwoofers, midrange cabinets, and high-frequency horns—that could be combined and configured to suit the specific requirements of different venues and events. This approach provided sound engineers with the ability to tailor the sound system to the acoustics of the performance space, resulting in better sound quality and coverage.

**1980s: Advances in Speaker Technology**

The 1980s brought about significant advancements in speaker technology. The development of new materials for driver diaphragms, such as Kevlar and polypropylene, improved the performance and durability of loudspeakers. Additionally, advancements in crossover design and digital signal processing (DSP) allowed for more precise control over the frequency response and phase alignment of multi-way systems.

## The Digital Revolution: Modern Multi-Way P.A. Systems

### The Impact of Digital Technology

**1990s: The Introduction of Digital Signal Processing**

The 1990s witnessed the widespread adoption of digital technology in audio systems. Digital signal processing (DSP) revolutionized the design and functionality of P.A. systems. DSP allowed for sophisticated crossover networks, equalization, and time alignment to be implemented with unprecedented precision. This resulted in multi-way loudspeakers that could deliver exceptionally accurate and consistent sound quality across a wide range of frequencies and SPLs.

**2000s: The Rise of Line Array Systems**

The early 2000s saw the emergence of line array systems, which represented a significant leap forward in P.A. technology. Line arrays consist of multiple speaker modules stacked vertically to create a cohesive and highly directional sound field. This design offers several advantages, including improved sound coverage, reduced feedback, and greater control over dispersion patterns. Line array systems quickly became the standard for large-scale concerts and events, with manufacturers like L-Acoustics, Meyer Sound, and d&b audiotechnik leading the way.

### Modern Innovations and Trends

**2010s: Compact and Portable P.A. Systems**

The 2010s brought a focus on portability and ease of use without sacrificing sound quality. Advances in lightweight materials and compact design allowed manufacturers to create powerful multi-way P.A. systems that were easy to transport and set up. These systems often featured built-in amplification and DSP, providing an all-in-one solution for small to medium-sized events.

**2020s: Networked Audio and Smart P.A. Systems**

The current decade has seen the integration of networked audio technologies and smart features into P.A. systems. Ethernet-based audio protocols, such as Dante and AVB, enable seamless digital audio distribution and control over large networks. Smart P.A. systems leverage AI and machine learning to optimize sound quality and performance in real-time, adapting to changing acoustic conditions and user preferences.

## Conclusion

The evolution of multi-way loudspeakers in professional audio systems is a testament to the relentless pursuit of better sound quality, reliability, and flexibility. From the early days of rudimentary mono loudspeakers to the sophisticated, digitally-controlled multi-way systems of today, each advancement has brought about significant improvements in the way sound is reproduced and experienced.

Modern multi-way P.A. systems offer unparalleled performance, capable of delivering clear, powerful, and immersive sound in any environment. As technology continues to advance, the future of P.A. systems promises even greater innovations, ensuring that audiences worldwide can continue to enjoy exceptional audio experiences.

The journey of multi-way loudspeakers is a fascinating example of how engineering and technology can work together to meet the ever-evolving demands of the professional audio industry. From the humble beginnings of the electrodynamic loudspeaker to the cutting-edge line array systems of today, the evolution of multi-way P.A. loudspeakers is a story of innovation, adaptation, and excellence in sound reproduction.