Doepfer

> 
> What sort of musical effects are you looking to get via tapping
> individual band outs from the Filterbank?

let me call attention of two specific applications for separate outs 
which some of you might enjoy.  I have to be a bit of a name 
dropper on this one.

One is running the output of a signal that is coming from a high 
Q band pass filter into the fixed filter and popping off the 
separate taps.  You will get an amazing sound from the minimal 
bandwidth of those two filters working in series.  If you control the 
bandpass with a random stepped sample and hold, then gate 
the outs of each of the fixed filter banks you are tapping off of with 
it's own envelope/VCA pair, things get even more interesting.  I 
will make an MP# this week of a piece of music i did years ago 
that used this effect.  it was a very cool effect.

The second application is even more fun:

Ok, I am old.  like mid-forties old.  I studied composition at Cal 
Arts.  I worked with Subotnick during the Sky of Cloudless Sulfer 
days.  I was one of the students who realized his control track 
score for SKY OCS from a score Mort wrote for us.  We recorded 
control signals which were generated form the computer in the 
Buchla 300 we had there. 

If you know that piece, if you know how control tracks work, this 
will be easy to understand.  Before midi, in order to pre-record 
information which you wanted to use to control a synth, you had 
to make a control track.  This was an audio track from a tape 
recorder, whose output was fed into an envelope follower in 
which voltage and trigger information was obtained.

If you have heard Sky of Cloudless Sulfer, or Until Spring for that 
matter, you'll get the idea that everything is synced, so massive 
control tracks had to be were used to pull it off, either that or a 
Buchla the size of a house.  A matter of fact,  Mort rented an 
Ampex eight track, dedicated four of the eight for control tracks 
and four only for the actual music - and that still wasn't enough 
for him. He needed more than four control tracks.  They were 
used to generate the pitch info, the meter  (timing), for the 
transcients, for timbre control and even spacial location of every 
single sound event in that piece of music.  This is why he 
needed only four track for audio.  He would set a patch up, start 
the deck with all the control tracks going through envelpe 
followers and the piece would basically play itself.  It's no big 
thing now with midi, but it was all voodoo back then.  We didnt 
know why Mort had us doing all this stuff and then he showed 
us and our mouths were on the floor. 

We spent about two months making the control tracks, which 
were very presicely scored, down to the second. He took those 
and recorded the entire record in one weekend.  30 minutes of 
music.

Because he needed more control tracks than the four channels 
would provide, we devised a way in which to put TWO control 
tracks on each audio track using the fixed outs of a Buchla fixed 
filter bank as a demultiplexer.  We would record two independant 
signals on one track of the deck They were nothing but bleeps of 
varying lengths. (short decay-only envelope sines used for timing 
later on and longer ones that swept panning, or opened 
envelops, etc).  Oneof the bleep track  was a low frequency sine 
tone, one was a higher frequency.  We would run the output of 
track through the fixed filter bank, tap off of the output which was 
the center frequency of the lower recorded tone, and then run an 
output which was the center frequency of the higher tone.

We fed both of those outs into two envelope followers.  

We were able to get two independant controls tracks on one 
recorded track with absolutely no cross talk.  We tried it with 
three but it started getting a little dicey.  I am not sure if that was 
due to the filter not being able to pick those off well enough,  the 
tape we were using to record them on (Ampex 406) or any 
harmonic distortion from the preamp in between .

Ok, using a fixed filter bank in this was is a bit archaic now, I 
admit, but it's an interesting story...no?

Anyway, if Doepfer releases this option, buy it.  It will be like a 
pulse divider - you won't use it every day, but when you do, you'l 
dig it.

Peter grenader