What is the Platinum MixMaster?
It's a mix processor designed for use in processing stereo signals primarily in the final mix down phase, though it needn't be limited to that: there are applications in stereo tracklaying and live sound. Our idea was to make a box which just makes the whole thing sound better (more like a "proper" mix) and do some general housekeeping tasks: sort of a one box version of the Focusrite Blue mastering equipment for the project studio. It's a line level device designed to sit in the mix inserts or between your console and your final stereo recording device, DAT, CD, cassette or whatever.
So The Mix Master is to stereo audio what spice is to cooking?
Yes- as a man who loves Indian food that's an analogy I'm very happy with! But as in cooking, you do have to add your "audio spice" carefully- too much will impair the flavour of the dish itself. A stereo mix is a very complicated signal, and it's very easy to lose transparency through intermodulation when processing it, much more so that with the sound of a single instrument.
What processing engines feature in The Mix Master?
Essentially it's a multi-band (spectral) compressor, with an EQ circuit and built-in image controller. It also happens to have a stereo expander, a limiter and a rotary output trim, as well as a 24 bit/96KHz capable digital output. Oh, and there are lots and lots of lights!
Just to make it look nice?
No, though I do like gear that is visually fun. The main purpose is so that the operator gets an immediate visual indication of what's happening as he alters the controls and they interact with the music. When you're mastering you have to pay partiular attention to levels, phase, extraneous noises etc. - after all you may be the last person who has the opportunity to do anything before it's released.
There's a lot on the unit. Does that mean it's tough to operate?
No, it's very simple - you can set up parameters to correct or enhance an entire mix in just a few seconds. Each section can be dropped in or bypassed individually like the other Platinum products, so you can set up each element independently if you choose. There's also a master bypass switch that allows you to compare the output with the unprocessed signal.
Why did you choose to use a spectral (multi band) compressor?
Because you don't want something in the low frequencies, for example a massive kick drum, to trigger compression across all the stereo signal. Splitting it into freq. bands means you get the kick drum, or whatever, only affecting compression of the low band, hi hat only compressing the high band, vocals only compressing the mids etc. The real benefit is that we can make a compressor that sounds very warm, whilst at the same time possessing extreme clarity- your mix is kept open and given room to breathe, rather than all the parts squashing each other up. In that sense it's a continuation of Focusrite's "compression signature" that is well known and respected from the Red 3 for example, which was in turn a development from the original Forte Series Console stereo output compressor I designed. I've also added controls to trim the amount of compression you apply to the high and low bands relative to the mid, which allows some very creative uses of the device.
Why have you got a limiter as well as the compressor?
The limiter is really there to protect the device that's next in line, whether it's a recorder or something else, whereas the compressor, particularly this one, is much more of a creative tool to make your mix appear to be louder and more "up-front". We've found that a lot of limiters although very good at the protection function sound just awful on some programmes because of their fast time constants, so for this one I developed a thing called "adaptive attack", which makes it a whole lot smoother.
What's an expander, and what's special about Focusrite's version?
An expander is like a soft gate - it reduces the overall audio level when there's not much happening - but whereas a gate is either on or off, the expander reduces the level more gently, in proportion to the smallness of the input. The one in the Mixmaster is a little unusual in that the threshold settings are very low i.e. it works right down at the lowest levels of the signal, down to the noise floor. If you have a very quiet section of music, for example at the beginning or end of a track, any background noises are very loud relative to the signal at that time, so you can hear them embarrassingly clearly. The expander will gently turn down the gain at these times, making any such artefacts inaudible. In this unit, as with the Compounder we use optocouplers as the gain control element which gives performance that you simply couldn't achieve with a VCA in this application.
Is the EQ a new design?
Essentially yes, though it's based on the principles of things like the ISA 110. An EQ for stereo programme has slightly different requirements than one for that's being used on a single channel of a multitrack recording, not least that the matching between the two channels needs to be very good! For that reason we've used switched frequencies for the HF and LF bands, and deliberately restricted the sweep on the MID frequency control, though the x10 switch still gives it enormous range. Also you don't want huge amounts of cut and boost, but you do need particularly good resolution in the 0....3dB sort of range. The actual curves of the EQ I picked to try and give enormous clarity and as much selectivity as possible, whilst keeping the thing very musical. Oh, and you're probably wondering what the TILT positions on the HF and LF frequency controls are. They give a very gradual slope enabling you to very gently and very smoothly alter the bass/treble balance of your mix.
Why do you need a phase meter?
In some cases your stereo master may be required to be reproduced in mono, so you have to have some idea of what the phase is like: you don't want everything to disappear into a massive null! And, if you're going to vinyl and something is badly out of phase at low frequencies, you physically can't cut the track. There's a lot more freedom with digital of course, but it's still very useful to know what's going on in terms of phase coherence. And it gave me an excuse to put in a blue LED.
What about the Image Controller?
It's one of the key processing elements. Basically it allows you to manipulate the stereo image as the name suggests- in particular it's really nice to be able to "make things bigger" - size can be important!
How do you "make things bigger" - are we not talking simply about making things louder?
No, "bigger" in terms of stereo image. If you want to sound spacious and "recorded on a grand scale" the easiest way is to create the impression that you've widened the stereo image. The way this is done is basically to amplify the difference between the 2 channels- see what's in the right channel but not the left and vice versa, and then to increase the level of that, whilst simultaneously de-emphasising the audio content which is the same in both the L and R channels (the mono bit). Because not everyone wants big and wide you can also make the stereo spread narrower if you want to- "small but perfectly formed" also has an appeal under certain circumstances. We've also provided some extra direct inputs to the unit that mix in further down the signal path i.e. just before the output so you can add for example an "in your face" vocal after making your backing tracks super-wide.
There's also a Balance control?
Yes, a 3dB trim either L or R, allows subtle correction of level imbalance between the channels, essential if you want to get the most out of the width control as well as keeping the whole mix central.
Could you use the Mix Master in a live situation?
Absolutely - it would nestle nicely between your mixer and main FOH system. There is something of an artificial divide between recording and live equipment- often what works well in one environment works equally well in the other - we are only talking about audio going from A to B after all. Some features, for example the limiter, have a direct relevance to live sound and installed audio- having the option to place a limiter across the output in this environment is an ideal way to save your club rig from the wayward enthusiasm of the visiting DJ who slowly increases the volume as the night goes on because his ears start to close down after midnight! Both the compressor and the Image Controller have the ability to make mixes sound a lot bigger (particularly in the bottom), so I can see a few going into clubs just for that.
This is the first time in the Platinum range that Focusrite have included a digital output - why?
Because many people want to process in the analogue domain, but now need the convienience of a digital hookup. With the world and his dog choosing digital media now, we decided that the time was right for FF to "speak digital" although the processing is still entirely analogue Class A - the best of both worlds. The other point is that all converters are not the same - by including Focusrite converters in the box we have total control of the final signal conversion - a key moment. After all, if you're going to the expense of making sure your analogue processing is true audiophile quality, it would be dumb to entrust your final conversion to a 2nd rate conversion device. Focusrite's converter is 24 bit, 128 times oversampled and can handle sample rates up to 96KHz, and most importantly it's being converted in a pristine electrical environment. Doing it in the average sound card inside a computer for example is the digital equivalent of trying to record chamber music on the hard shoulder of the M1 motorway!