Hands On - Lexicon PCM 70 (part 5)

Rich Resonances

Lexicon describe this effect as being “unlike anything that has ever appeared
before in an effects processor”, and I don’t 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 it’s amazing what you can do, even if it is really a novelty
effect. Don’t forget to try the ‘Auto Suspense’ program which
Lexicon advise, “is great for daytime soaps”!

Definitely Dynamic

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 don’t 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 hadn’t 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 wasn’t able to try this because I had already
returned my loan unit when I heard about it, but I’ll 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 isn’t 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:

• Aftertouch or velocity to Reverb Time
• Any controller to Reverb Time
• Any controller to Feedback
• Pitch wheel to pitches in Resonant Chords
• Any controller to Mix
• Note number to Pitch Master in Resonant Chords

It’s 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?

Long Life

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.