Affordable digital mixer previewed
It's all-digital. It's all-new. It has built-in stereo effects. And it wants to control your MIDI data. Bob Dormon gets a designer's-eye view on the Yamaha ProMix 01, and wonders how long he can live without it
It was like peeping over the garden wall at forbidden fruit - visiting Yamaha's pro-audio stand at the 1991 APRS show. At the time, the realms of home recording and pro sound were separated by a string of noughts, and technology percolated down in more of a trickle than a flood.
The very first 20-bit eight-track digital recorder and mixer combination, the DMR8, was on show, together with the DMC1000 digital mixing console. Terry Holton (then Yamaha's Professional Products specialist) was choreographing this double-act, recalling digital mixes with motorised faders obediently falling into line. It was an enviable display, and a far cry from the DMP7 MIDI-controllable mixer that Yamaha had wooed us with some four years earlier. The DMP7D had followed a year or so later, equipped with a multitude of digital ins/outs for DASH and ProDigi multitracks, as well as the AES/EBU and SP/DIF formats for two-channel material. The rack-mounted DMP9 with multiple outputs appeared some time later. Now, here was a major manufacturer bringing the benefits of digital technology into the marketplace at a realistic price. Digital mixers had learned to walk at last.
The A/V and classical arena were already well-pleased with the DMC1000, Deutsche Gramophon boasting no fewer than 50. But what about the rest of us? Well, some seven years on from the DMP7, Yamaha appear ready to scratch the popular itch and return to the needs of those on smaller budgets. The question is: how?
Under a veil of secrecy that would put the masons to shame, I went down to Yamaha's R&D premises in London, knocked three times and asked for Terry. The twisting corridors of workshops confused me sufficiently for him to dispense with the blindfold. Tapping in yet another security combination, Terry led me to the studio.
At first glance everything seemed in its place. The control room flanked by enormous Quested monitors, and various processors all looking pretty normal except... well, where was the desk? None of your British heavyweights here, just a DMR8 in the corner, a couple of computers, and a DMC1000. But hang on: what's that portable mixer doing in here?
The Yamaha ProMix 01 console is the first of an entirely new breed of mixer that has no equivalent DSP in the Yamaha range. Whereas DMP7s stole from the SPX90 technology, and the DMC1000 utilises SPX1000 processors, the ProMix has a new signal processing engine, the CDSP, which will no doubt be appearing in other Yamaha products in the future.
The ProMix 01 has 18 input channels, the first eight of which are balanced XLRs, the next eight balanced jack inputs, and the last two unbalanced jacks that appear on a dedicated stereo fader.
The first 16 inputs have an input gain range of -16dB to -60dB, allowing mic or line signals to be accommodated, and include a 20dB pad, with phantom power available for the first eight (XLR) inputs. However, there are no digital inputs; not even Yamaha's Y2 (digital cascade) input is supported. So I asked Terry Holton to explain the thinking behind the ProMix 01.
"The idea behind the console," he replied, "is to take advantage of the control you get with a digital system, rather than producing a mixer specifically for mixing digital audio signals. The primary applications are for a MIDI studio, keyboard sub-mixer, live sound, or a sub-mixer to a larger analogue console."
Interesting. However, as the ProMix 01 does have an SP/DIF digital output to allow interfacing with a suitable digital mixer, sampler, hard-disk recorder, DAT or DCC machines, it could equally be married up to a bigger digital desk such as a DMC1000.
And it's the outputs that really dictate the applications. The ProMix 01 is simply an 18:2 mixer with four aux sends - two digitally 'hard-wired' to internal effects processors, and two analogue sends (via an 18-bit D/A converter) to external effects devices or even a multi-track recorder. So it could be configured as an 18:4 mixer, if you were that way inclined.
As Terry says, it's the control aspect that sets this mixer apart. Every parameter can be controlled via MIDI. There are also 50 Scene Memories that can be accessed at the touch of a button. For live applications, you could have a whole set stored with specific changes available instantly.
In the MIDI environment, songs can be recalled from previous sessions. You don't just get the fader positions, you get the lot: mutes, EQ, panning, sends and returns, compressor/gates, digital effects, and channel grouping configurations.
Digital control is all very well, but all the button-pressing involved can be tedious in the extreme. Luckily, Yamaha haven't strayed much from the original DMP7 operating style. Two buttons above each channel fader select them for editing, soloing, and muting. And the large 240x64-dot LCD screen relays all the relevant information in an intuitive, uncluttered display.
"Under a veil of secrecy that would put the masons to shame, I went down to Yamaha's R&D premises in London, knocked three times and asked for Terry"
Navigating your way through the gamut of mixing parameters is made easier by the inclusion of arrow keys and an alpha dial to the right of the screen. And to the left, rows of dedicated function keys for Memory Store, Recall and up/down increments, EQ Library, Utilities, Metering, Pan/Phase, Compression, Cue/Solo options, Pairing or Grouping, Aux sends, and EQ help quicken editing still further. Repeated pressing on the EQ buttons (there's one each for Low, Mid, and High) moves the cursor through the gain, frequency, and Q/shelf options.
On the screen (above these parameters), the ProMix 01 actually draws a graph representing the EQ curve you've created. Groovy. Or should I say curvy?
There's also an EQ library with preset curves for the sonically challenged, and 20 user memory locations to store your tweaks de résistance. Ideal for fussy vocalists, and reviving favoured beat loops, among other things.
Panning also paints a pretty picture. The pan position of each channel is drawn as a conventional panpot. Below the 'pots', a horizontal slider displays the pan range and which of the 33 possible placements the currently selected channel (or pair) is set to. When channels are grouped together as a stereo pair, they are shown as a dual-concentric arrangement (a circle within a circle). One of the many neat features here is that stereo pairs can be trimmed, with one side panned more extremely than the other. Once that's set, the whole stereo image arrangement can be shifted left or right as an overall balance control. Using the alpha wheel to alter the panning helps bring these graphical adjustments back to a more familiar modus operandi.
Undoubtedly the most familiar feature of the console are the 19 motorised faders, although they perform a variety of functions in different modes. As individual channel faders, they operate as you would expect. However, the Pair/Group facility allows you to do precisely that. Faders can be paired so that stereo sources can be faded easily.
It doesn't matter which fader of the pair you touch as they'll both move together in tandem. That goes for the group function, too. Up to four fader groups can be assigned, allowing the control over any number of channels. This could be especially useful for functional live work when you might group a drumkit on the first six or so inputs, with groups for keyboard rigs, vocals and guitars on the remaining 12 channels. These configurations are clearly shown on the LCD, and any channel within the group/pair can be isolated, updated to a new position, and then reassigned.
Pressing any of the four aux send buttons immediately flips the faders to represent the send levels for each channel. Most of us are used to knobs for controlling aux sends but faders are fine, especially when they can be automated via MIDI or instantly recalled from the ProMix 01's memory.
Sends 1-2 are dedicated to the effects algorithms. These have yet to be finalised, as Terry was still appraising the virtues of a variety of effects included on the prototype chip at the time of my visit.
Regardless of the final configurations, the parameters available are laid out in typical Yamaha style, and one thing for certain is that pitch change will be available, which could be a laugh at gigs - how about the SPX 'Freeze' sampler program...?
Auxiliary sends 3-4 can be configured as a stereo pair for external devices, and all sends can be pre- or postfader.
The four aux sends have their own 'master' fader for overall send and return level, the status of this fader (like so many others) being dependent on the particular mode you've chosen. The aux returns (and the stereo input) can be EQ'd as a stereo pair, so that EQ is automatically duplicated for each side. This is all good time-saving stuff - something that even novices will appreciate. The ProMix 01 may involve a few button presses here and there (show me a desk that doesn't), but at least everything you need is in front of you.
In addition to the expected DSP functions, the ProMix 01 has three built-in dynamics processors. The mixer doesn't have any hardware inserts - it has software ones. So you can gate or compress a channel within the console, but there is no facility to connect an external device to the insert stage of that channel. There's nothing to stop you feeding a signal into a favourite delay or compressor before you plug into the mixer, but this isn't always satisfactory or feasible with some sources - like a microphone, for example.
"Despite the lack of knobs, working through the parameters is quick and easy"
Nevertheless, the three processors are available to any channel/pair. They all share the same bank of programs, so you can configure your own combination of gates and compressors. You could, say, have two gates working on some guitar tracks, with a stereo compressor acting on the whole mix. Two channels can be assigned to each (stereo) processor, and with gating effects, a 'key' channel can be assigned to trigger the gate operating on another channel. So, for example, synth pads or vocals can be punctuated in rhythm to the beat of a hi-hat, for that bizarre touch currently appearing on a multitude of dance tracks.
I tried gating a guitar track fed into the mixer from a DMR8 and found myself immediately familiar with all the parameters available. Unfortunately, it wasn't possible for me to then feed the gate's output into another dynamics effect such as a compressor, although you can still send the whole stereo mix into a compressor if you want to.
In detailed operation, the compressor presents no awkward surprises. If you set the compression ratio to infinity, then it acts as a limiter. Metering on the right of the display shows gain reduction and output level simultaneously, in a manner similar to dbx compressors. All the adjustments are smooth and clean, and despite the lack of knobs, working through the parameters is quick and easy.
You'll still have to exercise the grey matter on some things, though. Whether you're ducking, gating, or compressing channels, you would do well to plan ahead to optimise the obvious benefits these effects can bring when recording and mixing.
Besides the 20-bit, eight-times oversampled main stereo XLR output (to your two-track recorder or PA), the ProMix has an 18-bit monitor output, also with eight-times oversampling, for use in the control room and for headphone mixes.
ProMix 01 has a separate Cue page that provides an overview of all the various parameter settings available and/or in use, for a single ProMix channel. It's a very useful page and helps clarify the status of each channel.
In Cue mode, there are three listening options:
1) Stereo Fix - the main stereo output is sent to the monitor output
2) Last Cue - this applies to solo modes and enables only one channel at a time to be solo'd
3) Mix Solo - allows you to solo as many channels as you want.
There are two small knobs on the top right of the mixer to adjust monitor and headphone volumes. Above them is the switch for a two-track return. It's a pity there's only one of these, but the stereo input channel can be used for another two-channel source if need be.
Besides the 12-segment LED meters for the main stereo output, the ProMix 01 console has a dedicated Meters button which displays the status of the first 16 input channels on the main LCD screen. Both sets of meters have a peak-hold option, which is always a welcome feature on digital equipment - it means you can take your eye off the meters but still be able to check for clipping while setting channels up. It's this page that'll probably be returned to most often in general use.
Hidden behind yet another button are the miscellaneous features of the ProMix which most manufacturers describe under the blanket term 'Utilities'.
It's here that you'll find the various MIDI save and load dump options, as well as an oscillator section. The oscillator provides a variable output of 10kHz, 1kHz, 100Hz, and pink noise. I would have liked to have seen A 440 included, so that during a soundcheck you might be able to convince a grunge metal lead guitarist that he is out of tune... man! But it could still happen. This is a prototype, remember.
"Not only can you store the settings of your mix, you can store the altered parameters you set up on other MIDI gear, too"
You'd imagine that to have MIDI control of all the parameters of this console would involve a few shortcuts here and there. DMP7 owners, for instance, weren't able to have all their parameters available to them, and had to reassign certain functions to the detriment of others, as there were just too many to be represented on one MIDI channel.
And there lies the answer to the ProMix 01's MIDI specification. Basically, it uses more than one channel. As most serious MIDI users have multi-port MIDI outputs, thus expanding the available channels, Yamaha have assumed that the ProMix 01 will be controlled exclusively from a spare MIDI port. Hence, around six MIDI channels are used to communicate with the console using controller data (not note data) to control all of its functions.
To simplify things still further, it is unlikely that you'd ever need to change these assignments, and thus automated operation with virtually any software sequencer is rendered invisible. But, unlike some conventional desk automation, the ProMix doesn't reference itself to any form of timecode. All the automation commands are actual MIDI controls, so when and where they happen are dependent on the MIDI sequencer.
An absolute killer feature of the ProMix is that its faders can be switched to 'Local Off' mode. Here, the faders effectively become MIDI data controllers which you can then assign, store, or automate to control external MIDI effects units without affecting the current setup on the console. So not only can you store the settings of your mix, you can store the altered parameters you set up on other MIDI gear, too.
The applications for this feature are endless. No more digital delirium tremens as you squint at a poxy front panel, attempting to change part volumes on a tone module. Just sit right where you are and remotely control the sounds coming into your mixer.
The only drawbacks I can foresee are that with all this sitting around, you might end up with an entirely different repetitive strain injury. Haemorrhoid cream, anyone...?
There are some pretty obvious omissions from the Pro Mix 01's list of features. Like a disk drive, cartridge slot, or any other simple means of saving all your precious setup data to an external storage medium other than via MIDI.
The reason is simple: cost. Terry and the Yamaha design team have reasoned that onboard control is the key issue, and that if anything is to be sacrificed in the name of cost, it should be external interfacing.
The same rationale explains the lack of a digital input. Seeing as the console would have to work with an external clock source, the additional expense to maintain timing integrity would, the design people say, have proved prohibitive.
I'm happy to see a digital output (albeit SP/DIF - Lord help us if they choose to implement SCMS copy protection on this output), and the fact that the desk samples at 48kHz implies that consumer DAT recorders with digital inputs will be able to take advantage of digital interfacing, perhaps for the first time.
Finally, it would be nice to see separate inputs for tape returns, which the channels could then toggle between. But maybe that would be not just having your cake and eating it, but not putting on any weight afterwards, either.
Even at this early stage, it's clear that Yamaha have succeeded in creating an intuitive console that's very easy to use. The information given in the main display is uncluttered and quite radical - particularly the info relating to EQ parameters.
And the MIDI control opens up new possibilities in the field of remote mixing. Imagine having a ProMix 01 mix sent to you down an ISDN line while you send back your alterations to the mix (via MIDI) from your own ProMix 01 or software interface from the comfort of the hotel room.
It remains to be seen what the software houses will come up with. I understand Yamaha have been collaborating with them for some time. And I'm sure that by the time the ProMix 01 is in production, most software houses will have seen one, some will have touched one, and I'll probably own one. State of the art? It's just been redefined.
Price inc VAT: £1878
More from: Yamaha-Kemble, (Contact Details)
Review by Bob Dormon
mu:zines is the result of thousands of hours of effort, and will require many thousands more going forward to reach our goals of getting all this content online.
If you value this resource, you can support this project - it really helps!