Lexicon describe this effect as being unlike anything that has ever appeared before in an effects processor, and I dont think anything like it has appeared since either. The effect is created by six delay lines, each of which has its own delay and feedback controls. As you probably know, if you set a short enough delay time and apply feedback then any input will create a sequence of impulses which recur so rapidly that they are heard as a musical note. Multiply this by six and you have the ability to create chords, so that each bash of the snare drum will produce a burst of harmony at the output. You could probably achieve the same thing with six delay units, but Lexicon have been thoughtful enough to allow the user to program in musical notes, so you can program a chord very quickly rather than have to tune the delays very precisely. Each of these short delays with feedback is preceded by a longer delay so that the six notes can emerge in a rhythmic sequence. Once you get started on editing these programs its amazing what you can do, even if it is really a novelty effect. Dont forget to try the Auto Suspense program which Lexicon advise, is great for daytime soaps!
When the Lexicon PCM70 first appeared, it had one major new selling point, Dynamic MIDI, which allowed you to control parameters from the MIDI keyboard. Nowadays this is considered something that every serious effects unit must have, the only problem is that hardly anyone ever uses the feature! The blame for this lies with the manufacturers who on the whole spare no effort to produce brilliant equipment and then dont bother to show us how we can get the best out of it. It is human nature that if something is difficult to understand, then we are reluctant to put time and energy into understanding it - unless we can see clearly what the reward is eventually going to be. I would recommend that any manufacturer of effects units which incorporate the equivalent of Dynamic MIDI that they program in a few presets which use it, and most of all explain prominently in the manual what we are supposed to hear and tell us how we can get the best out of the feature. I have tried using it from time to time, but I always found my results interesting only in an academic sense and up until very recently (actually yesterday) I hadnt met one person who had used Dynamic MIDI or the equivalent function on another effects unit. But this one person who does use it has an application which indeed does appear to be musically interesting (thank you Steve Culnane). It is to use a flanging program on the PCM70 with the depth of the flange controlled inversely by note on velocity, so that the more quietly the keyboard is played the more effect is added, which apparently makes all the difference between a dull ordinary piano sound and one with life and sparkle. I wasnt able to try this because I had already returned my loan unit when I heard about it, but Ill certainly have a go the next chance I get. Until then, let me explain a little about to use Dynamic MIDI yourself:
Each Program has ten patches available by which a MIDI control source can change a program parameter. In Edit mode (which is when neither the Program nor Register LED is illuminated) Row 5 of the display is given to MIDI patches, and it would be most logical to start at position 5.0. If you spin the soft knob now you will see the possible control sources, which as well as MIDI controllers such as the pitch bend and modulation wheel - and all the rest - can be note on velocity, aftertouch, note number of last note played, or even MIDI clock rate. When your chosen control source appears, press the Load key. Now you can select the parameter you wish to control. Once you have got this far in PCM70 operation it isnt difficult to get the hang of the other Dynamic MIDI operations. and with patience almost everything you could imagine yourself wanting to do is possible, such as - as Lexicon suggest - these few:
Its up to you what you achieve with Dynamic MIDI, is it going to be interesting only in the sense that you have achieved a victory in the battle of man against machine, or will it be truly musically useful, something you will want to return to time and again?
In this day and age of disposable products it may come as a surprise to learn that the Lexicon PCM70, classic though it is, is still available (at £1792+VAT). I had assumed that by now it was surely discontinued but a phone call to distributors Stirling Audio put me right on that one. It goes to show that if you have a quality product, and support it with software updates, that the customers will keep on coming back. The PCM70, even against modern competition, is still a wonderful piece of equipment and I have no hesitation in recommending it, not only to buy, but to put at the top of the list of questions you would ask any studio you were thinking about booking. The question is Do you have a Lexicon?, and an affirmative answer will tell you that the studio, at least in the effects rack, is properly equipped.Come on the FREE COURSE TOUR