Doepfer

> Hi everybody,
>
> I have had a synthesizers.com system for a little while now, but
> I have recently been getting more euro-rack modules and I am
> thinking of switching over to euro entirely...
>
> Here is my question:
>
> Can digitizing/bit-crushing be done with a sample + hold like it
> can with dotcom S+H?
>
> http://www.synthesizers.com/pmwiki/pmwiki.php?n=Modules.Digitizer
>
> I have done this with dotcom and it works. However, I tried it
> with the S+H on th Moog CP-251 and it did not work, I heard
> artifacts of the clock speed in the sound... Is there someone
> with a Doepfer S+H that would be willing to test out that patch for me?
>
> I'm particularly interested in how it sounds to run drums through it...
>
> Thanks,
>
> Rafael

One has to distinguish between two types of quantizing/digitizing/crushing:

- level quantizing (that's what from my knowledge is normally called "bit
crushing")
- time quantizing (i.e. picking out samples at certain clock rate)

Level quantizing requires an analog-to-digital converter (ADC), a processor
that reduces the number of bits used for conversion and a digital-to-analog
converter (DAC) that outputs the quantized signal (with reduced resolution).
The quantizing becomes more "dramatical" as the number of bits is reduced -
down to one bit.

Time quantizing can be realized with a S&H provided that is a "real" S&H
(not a T&H = track and hold) and that it is fast enough for audio signals.
Normally S&Hs are planned for CV signals and the holding capacitor of the
S&H circuit may have to be replaced by a smaller value for audio
applications.

Both types of quantizing can be uses at the same time. E.g. the prototype of
our universal AD/DA module has a clock input that controls the sampling rate
(i.e. time quantization) and a CV input that defines the number of bits used
for conversion.

Best wishes
Dieter Doepfer