Hi Pierre

> BTW, I don't suppose anyone has access to more than a few of the BBD
> modules,

Dieter will be happy about each module, we buy ;-)))

> but I wonder if anyone could tell me which of the modules provides
> the best 'bit crunching' effect. I have a 256 stage BBD and it's pretty
> good for this but I was wondering whether one of the longer staged chips
> might not produce a wider range or more extreme effect.

I think you are looking for a kind of "intended reduction of signal
quality". There is no real bit crunching with a BBD Module. But there
are some side effects which you may want to use:

The first is caused by the sample&hold stage of the BBD with lower clock
rates (funny sounds happen, if the audio contains signals one octave
below and above the clockrate).
If you want to achieve this effect, then the answer already is given
with this explanation: the best module for "bit crunching" might be not
a BBD, but a simple S&H module. Feed it the audio signal through the S&H
and use a high tuned VCO or fast LFO as clock source.


The second side effect: with long delaytimes the analogue storage stages
(in principle: capacitors) loose content. This changes of course the
sound, because the waveform is changed.
This effect will happen in general with every BBD, but assumingly it
will be heavier at BBDs with more stages, because the 'capacitors' have
to be mechanically smaller.

Florian