Glen Trew reviews the new PSC Solice mixer

SEPT. 2009 NOTE: After reading this review, please read about the
important refinements that PSC applied to the Solice mixer
after this review. SOLICE REFINEMENTS, Sept. 2009

APRIL 8, 2009

It sounds great.

When listening to a Sennheiser 8040 through the Solice for the first time, I was betting this mixer had transformerless inputs. A quick call to the designer and PSC owner, Ron Meyer, confirmed that my ears may not have been imagining the low distortion clarity that is the signature of well designed electronically balanced transformerless mic inputs.

The standard features that professional location film/video production sound mixing engineers require are addressed in the Solice: 10-18VDC power into a 4-pin XLR connector, pre/post direct outs for each input, comprehensive communication system, input limiters that conjure up images of a cushion rather than a brick wall, and enough mix busses and outputs for whatever is normally planned (and enough left over for the inevitable surprises).

Consistent with other PSC products, the Solice is looking for that balance in the market of giving users most of what they need while saving on what they are willing to live without. In what may become a study in economics that other manufactures will take note of, PSC has come up with some interesting choices and unique elements relating to signal routing and monitoring.

Structurally, the Solice is well made and should last a very long time. Most of the abuse this mixer will see over its lifetime will be absorbed by the beefy side panels that are routed from aluminum billets. These panels rise stylishly above the level of the controls so that if the mixer is turned upside down on a table, there is no pressure on the knobs. The two side panels are grooved to accept a solid aluminum cover that can stop a brick, protecting the knobs and switches during storage and transport.

The 8 inputs are rear-mounted 3-pin XLR connectors. Normal enough, except for what will be a concern for many: The XLR connectors do not have latches, relying on a spring-loaded detent to grip the input cable. The decision to not use latches was probably to facilitate the manufacturing of the very compact design, and there is some advantage in being able to quickly remove the input cables in tight quarters. But, with this design, the risk of accidental disconnection does exist. My cart uses a sliding shelf for the mixer (a growing trend) which is constantly being moved back and forth, and eventually this movement could cause an input to disconnect, for which there is never a good time. I’m sure the input cables can be made reasonably secure, but the user will probably want to devote some attention to a stain relief strategy.

The inputs can be mic or line level with the flip of a switch. Input trim is by a single gain pot at the top of the board, just where it should be. For what must be the first in ten years for a new product, in addition to standard 48V phantom power, the Solice has included a power choice for long-defunct T power microphones.Direct outs, prefader or postfader (more on this later), are available on 1/4″ TRS connectors with the same output level as the main outputs. The eight main outputs are available on XLRs and a 37 pin sub-D connector. The eight return input are available only on the 37 pin connector. Power comes in through a standard 4-pin XLR, and anything between 10VDC and 18VDC is OK. The top panel has a BNC connector for a work light, for which I understand a low current bright LED miniature gooseneck light will soon be available.

Input Metering
Wisely taking a cue from the Sonosax SX-ST mixer (who may have taken it from the Zaxcom Cameo mixer), the Solice has been given input metering that has two separate LED bars for  prefader and postfader points. Multi colored LED indicate limiter function. Combined with the output metering comprehensive metering of this type allows the operator to optimise the gain structure precisely.

EQ and Low Cut
A variable Low Cut control (referred to by PSC as “High-Pass”) is right where you’d expected it – under the trim pot – but it may take some getting used to because it operates in reverse from the traditional standard. For maximum reduction of rumble (increasing the frequency at which filtering begins, 200Hz max) the control is turned fully to the left (counterclockwise). Turning the knob fully to the right decreases the filter’s frequency to 18Hz. This means that the position of the Low Cut filter knob operates like a low freq EQ control, where turning clockwise increases the low frequencies. While the direction of this control can be logically explained, it is the opposite of all other such mixing boards I am aware of. The slope of the Low Cut is listed at 12dB/octave, which is less that the steeper slope of 18dB/octave I generally prefer in a such a filter, but does seem to effectively and unobjectionably control ambient rumble.

The EQ control has three bands with frequencies that lend themselves to what I believe most production sound mixers need EQ for: blending dialog microphones in their mono mix. The center frequencies are: 8kHz for highs, 100Hz for lows, and variable from 1K to 3K for mids. With a maximum swing of +/-10dB, the person at the controls will find that they can turn the knobs further with finer resolution compared to other mixing consoles. For example, the EQ controls of Mackie, Sonosax, and Cooper have +/-15dB of adjustment, which, though typical, means that a small movement makes a relatively large change for the needs of a production mixer, when compared to the EQ on the Solice. However, this is a tradition that the Solice departs from with my full approval because, though I will EQ on the set as much or as little as my ears determine is needed, in 30 years of production mixing I have never  needed +/-15dB of EQ to blend and normalize voices in a mono mix. Never. Therefore, without compromising the needs of on-set EQ, the Solice’s control swing of +/-10dB will allow more physical movement of the controls resulting in higher resolution adjustments. So, Solice owners, if you were afraid to move your EQ knobs beyond 2:00 or 10:00 on a Cooper mixer, remember that you should happily turn the Solice EQ knobs further to achieve the same result.

Limiters and their use are often-debated topics. An “old school” of thought is that limiting and compressing should be completely avoided when recording original tracks, thereby maintaining the natural dynamics of dialog, relying on limiting only when the other option is overload distortion. But a more practical school of thought realizes that if you wait until just before distortion to start limiting enough to avoid overload, sufficient limiting will often be noticeable and objectionable. Also, when needing to ride levels on widely varying multiple voices, properly utilized compressor/limiters can often do a smoother job than human reflexes allow our fingers to do. So there is a valuable place in our jobs for good compressor/limiters, and those in the Solice seem well suited for the task. They are the “soft-knee” type, meaning that the limiting ratio increases gradually as the input level goes past the activation threshold. When a signal is high enough that the threshold has been reached, the Solice limiters begin with an approximate 3:1 ratio, which gradually increases to 50:1. The threshold and ratio settings are not externally adjustable, so the activation of the limiter is essentially controlled by the user with the input trim. But with the limiter activated, full deflection of the mix buss meters is almost impossible, which means, according to its peak meters, that a significant amount of available headroom will never be used when the limiters are on. In my opinion, an external threshold adjustment and a more gradual ratio increase would be more conducive to mixing and recording original dialog tracks, but these are such a vast improvement over the brick wall limiters found on Cooper mixers, I would be happy to use them in production for a while before deciding to ask for any changes.

[NOTE (April 6, 2009): During a conversation with designer/PSC owner, Ron Meyer, he mentioned plans to change the limiter’s threshold settings to make better use of the dynamic range of the mixer and the recorder it feeds.]

Tone, “0”, and Metering
OK, here we go…  Metering, line-up tone, and “0”, are probably the most important misunderstood concepts in audio, which, I’m afraid, is perpetuated somewhat by manufacturers using a seemingly random variety of scales and reference points.

The PSC Solice MAIN OUTPUT meters have a “+12” at the far right, and a “0” that is 12dB to the left of that. The “0” is where the internal tone lines up with the MAIN OUTPUT faders all the way up. Here’s where the confusion is likely to happen…

The common accepted “0VU” reference for digitally recording original dialog tracks is 20dB below digital max (full scale), notated as -20dBfs. However, the Solice outputs begin clipping at 15 dB above the meter’s “0”. This means that if a modern digital recorder’s standard 0VU reference (-20) is lined up this mixer’s “0”, then the mixer will clip 5dB before digital max is achieved at the recorder.

Here is what I believe is the proper procedure to make the most of the Solice’s headroom when recording digitally: With the Solice’s tone at the “0” position (default level when the main faders are full up) adjust your recorder so that this tone lines up to 12dB below full scale (-12dBfs). Your recorder is now properly aligned with the mixer. Have a nice day.

This setting allows the mixer, before clipping, to go 3dB beyond the recorder’s maximum, which will allow a recorder’s input limiters (those that have them) to save the day even if the Solice’s output signals go up to 3dB past its full scale.

Since the standard recorded line-up tone for original dialog tracks is generally accepted to be 20dB below max (-20dBfs), if using the Solice’s tone as the source, pull back the MAIN OUTPUT faders until the tone register’s -20dBfs on the recorder. You can now record a proper 0VU reference tone for post production. (When finished recording the tone, be sure to put the main faders back to the full up position for optimum gain structure.)

Signal Routing, Outputs, and Monitoring
The most dramatic difference between the demands of the old standard mixers and those designed for today’s productions is the need for more versatile signal routing; recording 8 or more unique tracks is now the norm. Plus, more outputs are routinely needed for a variety of uses including two or more channels of wireless monitoring, video assist, a couple of channels of music playback, public address for the AD, the EPK crew, and on, and on, and on. In order to have most of the appeal of more expensive mixers, PSC made some interesting and creative choices. The result will be some questions about how to achieve the needed mixes, outputs, and monitoring, but I found that the answer was always there if I was willing shift gears a bit.

Each of the 8 inputs has its own direct output. While this is not a new idea, the Solice is the only mixer in this class that has the ability to switch this output from prefader to postfader with a panel-mounted switch (some other brands require special soldering or internal switches). Kudos to PSC for this. They even took it a step further by giving each direct output its own level control. Since these outputs are usually used for isolating single microphones onto their own recording track, at first I could not see any practical use for the level control. After all, an isolation track feed should be at standard line level, with fine-tuning done at the recorder inputs. But when there is a need to use the direct output for something else, such as feeding a PA system, for example, the level control could be very handy. In this situation, think of the direct output and level control as a “one mic AUX send”. So, even more kudos to PSC for this one. Just be sure to keep the level controls fully up when sending to an iso track, using the trim knob to control the level as needed.

[For this next section, consider that the most commonly used standard for mutitrack recording of dramatic film and video production sound is “mono mix to channel 1, then all mics isolated prefader to the remaining tracks”. Also keep in mind that the somewhat questionable practice (in my opinion, anyway) of “radio mics mixed to one channel, boom(s) mixed to another” is a hold over from its beginning decades ago when trying to make the most out of the second channel of a Nagra IV-S. Those days, thankfully, are mostly gone.]

The Solice has 8 mix busses, which PSC refers to as “main ouputs”. The outputs of these mix busses can be thought of anyway you like: a stereo mix for the recorder plus 6 AUX mixes; a mono mix plus 6 iso channels to the recorder plus an AUX mix for video assist…  you can do whatever you want with them. The point is that there are not additional AUX busses, which, I think, was a wise choice in saving cost and panel real-estate, because the AUX sends of film/video production mixers are almost always full up anyway.

Each input can be assigned to any and all mix busses (“MAIN OUTPUTs”), prefader or postfader. This is an important feature that gives the ability of the mix busses to be used as prefader sends to the recorder. This ability also allows track assignments to be changed at the mixer’s panel instead of re-patching the cables going into the recorders.

Here’s where it gets a little odd…

Each of the 8 inputs can be assigned independently to mix buses 3-8. But a single switch on each input assigns it to MAIN OUTPUT-1 and MAIN OUTPUT-2 at the same time, relying on the pan pot to then route the input to MAIN OUTPUT-1, or MAIN OUTPUT-2, or a mix of both). This means that if an input is assigned postfader to MAIN OUTPUT-1 (normally the mono mix) it can only be postfader to MAIN OUTPUT-2, as well. So, if using the common convention of “mono mix on buss-1 to recorder track-1, and prefader iso’s on remaining tracks”, you cannot use MAIN OUTPUT-2 for your recorder because it will always be postfader. In a way, this is just as well because the Solice’s monitor section does not allow a mix buss to be monitored by itself anyway (more on this limitation later).

With this dilemma in mind, a reasonable configuration is to always use MAIN OUTPUTs 1 & 2 as postfader mono or “stereo” mix channels (allowing for the antiquated radios/boom “split tracks” convention, if insisted), then using the direct outs for prefader iso’s on remaining tracks. This was, no doubt, the intention of the design, but since the “mono mix and prefader iso” convention has pretty much replaced the 2-channel “split track” convention, MAIN OUTPUT-2 will almost always be usable only as a duplicate of output-1 (with the pan pot is centered). This being the case, output-2 could be used as another output for sending the mono mix to Comteks or video assist, etc. If you’re thinking of using the pan pot to create a different mix to MAIN OUTPUT 2 for Comteks or Video assist, think again, because you can’t listen directly to output-1 without also hearing output-2, giving a false impression of your mono mix; as explained…

Monitoring…. Efficient or limited?

Even the genius who immediately figures out the 1-2 assignment scheme will pause – possibly for along time – when assessing the Solice’s monitoring options. So, be prepared to read the following description several times:

There are 4 monitor circuits lined up left to right above the master fader section, labeled “DIRECTOR”, “BOOM-1”, BOOM-2, and “MIXER”. (I probably would have reversed the order, but this is totally a matter of what you get used to; heck, they even drive on the wrong side of the road in some countries). Each of these 4 circuits has 6 selections, but, as seen in the photo, they vary on each circuit (no two of these circuits has the same selections).

Each of the 4 circuits can choose to monitor 1&2, 3&4, 5&6, and 7&8. Position #5 of the DIRECTOR monitor is “iPOD” (there is an input called “iPod” for piping mood music around the set), which is not shared with the boom monitor choices. Position #1 of BOOM-1 is “CH1” (input 1), but position #1 of BOOM-2 is “CH8” (input 8). These choices seem to be personalized for the way a few might like to work, and it is a bit confusing that the selections vary in all four monitoring circuits as they relate to the knob positions.

The MIXER and BOOM-1 have a selection to monitor input-1, the design assumption being that the first boom usually goes into input 1 (for everyone but me, maybe). But the BOOM-2 input monitor choice is input-8, the design assumption being that the second boom will go into input 8 (which is where I usually have the first boom!).

An effort to include features that appeal to a few resulted in the omission of a basic monitoring option needed by nearly everyone: A mono mix to a single mix buss cannot be monitored by itself. In other words, the main outputs can only be monitored in pairs; there is no option for listening to just MAIN OUTPUT 1 or just MAIN OUTPUT 5, etc. How serious is this? I estimate that the vast majority of film/video production sound mixers, boom operators, and directors monitor the mono mix from buss 1 in both ears, but with the Solice this cannot be done. However, always using output channel 1 and output channel 2 as the mono mix will somewhat negate this limitation, as will the return monitoring scheme described in my suggested configuration points below.

Those who record in M/S stereo will be happy to see a M/S decoding switch in the monitor option. This same switch has “MONO” and “STEREO” positions. While the MONO position may be handy for the radios/booms split-track crowd, it does not solve the inability to listen to just one mix bus.

To make the best of the Solice’s routing and monitoring limitations (which can be worked with very well, as I discovered) here is how I would use it with an 8-input, 8-track recorder:

• Assign every input, postfader, to MAIN OUTPUTs 1 and 2
• Connect MAIN OUTPUT 1 to the recorder, and assigned it to recording track 1 (mono mix)
• Keeping the pan pot centered, MAIN OUTPUT 2 will always be a duplicate of the mono mix, which I would use to feed video assist (since outputs 1 and 2 share the same master fader, there is no chance of forgetting to have this feed on).
• The prefader direct outputs would then go to recorder tracks 2-8, giving 7 prefader isolation tracks. (When using 8 inputs, a decision would have to be made as to which mics have to share a recording track).
• This leaves MAIN OUTPUTs 3-8 to be used for whatever else: music playback, EPK crew, Comteks, etc.
• Connect the headphone output of the recorder to the Solice’s return inputs 1 & 2. Assuming that the recorder headphone outputs have the ability to listen to single track (like the Deva series does), this accomplishes the need to hear only the mono mix in both ears. I strongly recommend monitoring the return inputs at all times until there is a good reason not to. This is the only way to verify that the signal is getting to the recorder. Also with this return monitoring strategy, playback is heard whenever the recorder’s playback button is pressed. If the recorder has solo (PFL) capability, you can also solo the prefader tracks during record or while playing back. Monitoring the recorder in this way makes the Solice’s single-buss-monitoring limitation almost a non-issue.

Communication
The Solice has a very capable 3-channel communications section, allowing private 2-way conversation between the sound mixer and two boom operators, using the PL button. A separate COM button allows also taking to the “director’s” monitor without going onto the main outputs.

When the sound mixer presses the PL button, both boom operators will hear their boss. The boom operators can key their circuits remotely (such as with a belt-worn box) to talk privately to the sound mixer and to each other. Whoever talks will also hear their own voice in their headphones.

The sound mixer’s external slate/PL input and the boom operator’s talkback inputs are mic level and have 5V for powering electret condenser microphones. There is no external provision for adjusting the level of these mic inputs, but the level seemed to be just about right when testing with the Sony MDR-7506 headset conversion by Remote Audio (using the electret mini headset mic option). The mic inputs can be used with a dynamic microphone, but since there is no switch to turn the bias voltage off, an external DC blocking circuit is required, and a weak level should be expected (just go with the condenser mic).

The same boom cable and talkback system made by Remote Audio for the Sonosax mixers works great with the Solice. The boom box and extension cables are the same; the only difference is the mixer end fan-out (call to specify Solice if ordering).

Conclusion
The PSC Solice mixer will find a well-deserved, very successful place with film/video production sound pros, because of its balanced combination of extensive routing ability, utility, and moderate price. But what may be the Solice’s most valuable feature is PSC’s proven reputation for standing behind its products.

Plus, it sounds great.

PSC Solice manual (492K PDF)