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.