From mkarl2@uswest.net Sat Aug 06 08:11:55 2005
Subject:The CRACK - MS Pro/LoPro, Voce V5, Y* P90 piano

THE CRACK

First, the gear: Yamaha P90 digital piano MIDIed to VOCE V5 'B3'
module. V5 volume out to Morley ProII volume pedal, to Motion Sound
Pro3T and LoPro. Piano audio going through PA, not the issue here.

(Note on the MIDI connect: Yamaha disagrees with Voce on the location
of middle C, so I had to transpose the P90's MIDI output by 12
semitones. I also suppressed sending Midi patch change to the V5.)

Anyone who has the MS combo learns how to balance the pre-gain and
post-gain for either clean or tube distorted audio. I was playing in
the studio and rediscovered something I only hear occasionally
playing live. I turned down the post-gain / final volume stage to
less than ¼, with the pre-gain set straight up.. going for tube
distortion, in other words.

The Symptom: I was fooling around layering P90 piano with organ,
doing the very crunchy chordal riff in the Band's 'Chest Fever'. The
MS 'Leslie' was grunting satisfactorily. But occasionally, during
chord changes, an audio artifact I can only term a 'crack' came out
of the MS.

Remember this is at extremely low volume. Playing around it seemed
related to sustain pedal – CC64 – lifts. But not reliably. There is
a peculiarity about the sustain pedal on the P90, it's got a feature
for 'half-pedal' function on two of the internal grand piano patches.

So I can't break this down. It does NOT happen when the MS is set
more balanced, with more equal pre- and post- gain functions, but the
overall volume doesn't seem to matter. I wonder what MIDI is
getting sent with this mystery 'half-pedal' function (CC64+something
else?), but once again, I use the pedal constantly – since
I'm 'really' a pianist. This crack or snap out of the MS isn't
necessarily momentary volume changes, either, because it happens when
I'm not pumping the Morley pedal at all.

So it IS related to the pre-gain tube circuit somehow, and if I don't
go for distortion on the MS, then I never hear it. I guess I should
send an email to John Fisher of Motion Sound.

Any ideas? There's a very few in this forum with this combination of
gear.. have You heard The Crack?

Thx

Karl