TEST: SPL Phonitor 2

 A headphone amplifier for nearly 1,300 euros? Anyone who views the SPL Phonitor 2 from this perspective has already lost. Much has been written about monitoring through headphones. Rarely has a topic been so controversially discussed over decades as mixing without proper monitors. Why is that? Wouldn't it be wonderful to work on your individual output anytime, regardless of time and space, entirely according to your personal mood?

This is precisely the goal SPL pursues with its Phonitor series, and now they have brought the successor to Model 1 to market with the SPL Phonitor 2, which boasts some meaningful extensions in addition to its predecessor.

Construction

Why do we actually prefer working with speakers and normally only take headphones on board as a supplement? Well, there are primarily two points that cause problems for the inclined audio engineer when operating purely with headphones. For one, we always perceive music, or all audio signals, in a spatial context, which is not the case with headphone operation. The ultra-stereo setup of headphones at 180 degrees doesn't really occur in nature to this extent and confuses our brain more than it helps. Even the legendary artificial head recordings from several decades ago were characterized by generating the ultimate spatial resolution through headphone operation. A brilliant principle, but one that failed due to the user's inability to handle it.

Furthermore, the majority of our music is still generated for the classic stereo triangle, which spatially cannot be generated in normal headphone operation. Frequency-wise, headphones can already make up a lot of ground depending on the quality level, but the haptics of a recording and especially the depth layering of the spatial image go completely to the dogs here. This is where the first peculiarity of the SPL Phonitor 2 comes in, and explains over the course of the test why one should put down nearly 1,300 € for a headphone amplifier when even every entry-level console nowadays has at least one headphone output.

Speaking of haptics, anyone playing with the thought of acquiring the SPL Phonitor 2 should have a tidy workspace. With dimensions of 305 mm x 277 mm x 99 mm and a hefty weight of 4.3 kilograms, the device spreads a special kind of haptics on its four rubberized aluminum feet. An extremely massive construction, exclusively the best components in the exterior and interior, and a thoroughly noble appearance immediately suggest that this is not just a normal headphone amplifier that simply makes things "loud".

As with many other products, the company from Niederkrüchten also follows the principle of 120-volt technology (symmetrical +/- 60 volts) with the Phonitor 2, which has a significantly better signal-to-noise ratio, higher dynamics, and in particular a larger headroom, making the product sound more "relaxed" in its entirety. Perhaps some of you have already sat under headphones for several hours in an OB van or on other occasions and inevitably experienced fatigue in attention. This is not only due to poorly fitting headphones, but also an operational amplifier that, even if almost inaudibly, constantly works at the limit, straining acoustic perception significantly more than a product that only operates in the middle range.

Unlike its predecessor, which could only manage one stereo source in the input area, the SPL Phonitor 2 can handle three different input sources, making the product also a stereo preamplifier. On the front panel, as with its predecessor, a large volume potentiometer adorns the panel, allowing adjustment from 0 to -97 dB. The special feature, however, is that the control is motorized and can be operated by an infrared remote control if needed via a learning function. Nice for someone who wants to integrate the Phonitor into their Hi-Fi setup, but probably the exception in the studio. Two large, backlit VU meters, which can be switched in input sensitivity between 0, +6dB or +12dB, provide information about the applied level. Overload indicators have been omitted due to the immense headroom of the 120-volt technology.

The sophisticated electronics of the SPL Phonitor 2 can be operated via a total of 7 small toggle switches and 4 additional rotary controls beside the volume control. The Matrix parameters Center, Angle, and Crossfeed quickly attract the user's attention, as this is where the product's special features are bundled. The Angle rotary switch simulates the stereo width of the set-up speaker pair in six different angles (15, 22, 30, 40, 55, 70 degrees). Crossfeed also regulates the crosstalk of the speakers in six stages, while Center regulates the volume of the phantom center to balance the center signals, which are always reproduced a bit quieter in headphone operation. This area alone already shows how elaborately the respective, personal listening experience can be emulated via the preferred monitors.

The Cr/A, off, all toggle switch allows for a quick A/B comparison by activating all three Matrix controls, only Crossfeed and Angle, or deactivating everything. The Solo switch allows you to listen to either the left or right stereo signal individually, optionally Solo-in-Place, or via the activated Mono switch also Solo-in-Center. The Phase switch in combination with the Mono switch also allows you to find phase cancellations very nicely and quickly, without having to struggle through software-based correlation displays. The Laterality control is a very high-quality balance control that, unlike standard versions, has a significantly higher resolution and doesn't regulate down to zero at the stop, which would be pointless in practice anyway.

On the rear, the Phonitor has 2 balanced XLR Left/Right inputs and an XLR stereo output. Additionally, the SPL Phonitor 2 has a stereo RCA input compared to its predecessor. There's also a learning switch for the infrared remote control and the IEC socket. On the bottom of the housing are 4 additional mini switches with which you can adjust the output levels. All output levels can optionally be raised by +6dB or +12dB. Switch 3 raises the RCA level from -10dB to studio level 0dB, and switch 4 loops the signal without further processing except for the phase switching to the line output. This circuit is useful if you don't want to use the SPL Phonitor 2 as a preamplifier or monitor controller.

Practice

It's always difficult to capture listening impressions in written form. However, it's particularly difficult when it's not just about the personal listening impression of frequencies, but rather about a dynamic range that also plays out in the operating voltage range. To anticipate, even if the 120-volt technology is often dismissed as esoteric nonsense by some contemporaries, you can hear a clear difference. The sound impression both in near-field playback or in headphone operation is significantly softer and sounds less "strained". Ear fatigue decreases and the overall sound perception itself improves. Truly impressive.

In terms of speaker simulation, however, there's nothing to discuss, as the SPL Phonitor 2 plays in its own league without any competition. Even in the previous version, I was impressed by the truly incomparable ability to very well replicate my preferred near-field monitors, independent of room size and seating position. The unnatural listening behavior via headphones with the center in the head can indeed be individually faded out and processed to the highest degree via the product's matrix, so that mixing via headphones becomes tangible for the first time. Once you've "grasped" the workings of the parameters, you can literally build your own environment using the matrix. All switches result in a practical way of working and offer manifold possibilities for tonal control.

For my part, I find the mere fact that with the SPL Phonitor 2 you have a portable tool at hand that you can take to any studio along with your favorite headphones to be very helpful. If you train your hearing in parallel to your favorite near-field monitors on the aforementioned constellation, you are practically completely independent of the local monitoring situation. The laborious transport of your preferred monitors for rental productions in foreign studios is completely eliminated.

Expanding on the Phonitor 2's Capabilities

While the core features of the Phonitor 2 are impressive, it's worth delving deeper into some of its more nuanced capabilities and how they can benefit various audio professionals.

For mastering engineers, the Phonitor 2 offers a unique opportunity to check how their work translates to headphone listening, an increasingly common consumption method for end-users. The ability to simulate different speaker setups allows for a quick check of how a master might sound on various systems without the need for multiple physical setups.

Recording engineers working on location might find the Phonitor 2 invaluable. When working in acoustically challenging environments, the ability to have a consistent, reliable monitoring solution that simulates a well-tuned control room can be crucial for making informed decisions during recording.

For post-production professionals, particularly those working in film and TV, the Phonitor 2's spatial simulation capabilities could prove useful when working on surround mixes. While not a replacement for a full surround setup, it could provide a useful reference point when a full system isn't available.

Educators in audio engineering programs might consider the Phonitor 2 as a teaching tool. Its ability to switch between standard headphone playback and simulated speaker setups could help students understand the differences between these monitoring methods and develop critical listening skills.

The 120-volt technology employed in the Phonitor 2 deserves further exploration. While the audible benefits are clear, it's worth understanding the technical reasons behind this choice. The higher voltage allows for greater headroom, which means the circuitry is operating well within its capabilities even during peak moments in the audio. This results in lower distortion and a more open, relaxed sound. It's particularly beneficial when dealing with transient-rich material like percussion, where the extra headroom allows for more accurate reproduction of quick, high-energy peaks.

The motorized volume control, while perhaps seeming like a luxury feature, can be quite useful in professional settings. For instance, it allows for precise recall of volume settings, which can be crucial for maintaining consistent monitoring levels across sessions. The ability to control this via remote could be beneficial in certain workflow scenarios, such as when making adjustments from the "sweet spot" in a control room.

The multiple input options on the Phonitor 2 make it more than just a headphone amp. It can serve as a high-quality monitor controller in smaller studio setups. The ability to switch between three different sources could be useful for comparing mixes across different playback devices or for integrating multiple workstations in a single setup.

The VU meters on the Phonitor 2 are more than just visual flair. In an age where many engineers rely heavily on digital meters, having high-quality analog VU meters can provide a different perspective on levels. The ability to adjust the sensitivity of these meters adds to their utility, allowing for precise monitoring across a wide range of input levels.

One aspect of the Phonitor 2 that shouldn't be overlooked is its potential as a reference tool. By providing a consistent listening environment regardless of the physical space, it allows engineers to have a reliable point of comparison. This can be particularly useful when working in multiple studios or when collaborating remotely with other professionals.

The phase and mono switching capabilities of the Phonitor 2, while seemingly simple features, can be powerful diagnostic tools. The ability to quickly check for phase issues or evaluate a mix in mono can save time and help catch problems that might be missed otherwise.

It's worth noting that while the Phonitor 2 excels at speaker simulation, it doesn't address the frequency response characteristics of the headphones themselves. Users will still need to be aware of the specific colorations introduced by their headphones. Some professionals might choose to pair the Phonitor 2 with headphone correction software for a more complete solution.

For those working with binaural or immersive audio content, the Phonitor 2's crossfeed and speaker angle controls could prove invaluable. These features allow for fine-tuning of spatial perception, which could be crucial when crafting or evaluating 3D audio experiences.

The build quality of the Phonitor 2 is worth emphasizing. In an industry where equipment often needs to withstand the rigors of regular studio use or frequent transportation, the robust construction of the Phonitor 2 is a significant advantage. The use of high-quality components throughout suggests that this is a piece of equipment built to last, potentially offering better long-term value despite its higher initial cost.

When considering the Phonitor 2, it's important to view it as part of a larger monitoring strategy rather than a complete solution in itself. It complements rather than replaces traditional speakers, and its true value becomes apparent when used in conjunction with well-understood headphones and in comparison with other monitoring options.

The potential impact on workflow shouldn't be underestimated. By providing a consistent, speaker-like reference point, the Phonitor 2 could allow for more efficient use of time when working away from a main studio. This could be particularly valuable for producers and engineers who split their time between multiple workspaces or who often need to make critical decisions outside of their primary environment.

Conclusion

With the SPL Phonitor 2, SPL has a product on the market that continues to cover an area without competition, the practicality of which cannot be rated highly enough. In addition to its function as an excellent preamplifier in 120-volt technology, it is particularly the outstanding function of speaker simulation that catapults the product into a league of its own.

In conjunction with high-quality headphones, the product enables an unprecedented variety of design in terms of monitor imaging, which can be managed entirely according to personal taste. After an appropriate familiarization period, rooms, times, monitor manufacturers, and seating positions no longer play a role and enable the sound engineer unprecedented possibilities in terms of productivity.

A discussion about the price of the product can be confidently spared. A product that is not only developed in Germany but also completely manufactured there and additionally equipped with only the best components in every respect cannot be produced more cheaply under these circumstances. The only question that remains is whether one has this budget available, but not whether the product is "worth" the price.

Absolute top class!

In the broader context of audio technology, the Phonitor 2 represents an interesting bridge between traditional speaker-based monitoring and the increasing prevalence of headphone use in professional audio. As more content is consumed via headphones, tools like the Phonitor 2 may become increasingly relevant in ensuring that mixes translate well across various playback systems.

It's also worth considering the Phonitor 2 in light of emerging immersive audio formats. As technologies like Dolby Atmos and Sony 360 Reality Audio gain traction, tools that can accurately represent spatial audio information over headphones may become increasingly valuable. While the Phonitor 2 is primarily designed for stereo content, its underlying technology could potentially be adapted or expanded to address these new formats in the future.

Ultimately, the SPL Phonitor 2 is a specialized tool that addresses a specific need in the audio production world. Its value will depend largely on individual workflows and requirements. For those who frequently work on headphones or need a reliable reference when away from their main monitoring setup, the Phonitor 2 could be a game-changing addition to their toolkit. For others, it may be an interesting but non-essential luxury.

As with any audio tool, the true test of the Phonitor 2 will be in its long-term use across a variety of projects. Initial impressions are certainly positive, but its real worth will be determined by how it influences the quality and efficiency of users' work over time. For now, it stands as an intriguing and innovative approach to a long-standing challenge in audio production.