Hi ele
> i'd want to make all sorts of sequences of numbers and waveforms and
> send them out of the computer as smooth cv's.
> this is what the dac resolution is all about, right a 12 bit dac won't
> be able to generate a smooth slow increase from one voltage to another,
> or replace a real sine wave lfo
I think you hang on a rumor, that isn't really true for everyone. But it
depends on what kind of Sound you want to do. Example:
First thing: there is no real sine LFO in modular systems (sorry, I do
not know any), because they would require a LC-based generator. Every
digitally created LFO will be a better sine but an analogue created one.
Second thing: The usablilty of a modulation source depends mostly on the
usage of the modulation. Example:
You have a rythm orientated music and want to do a modulation of a VCO
over one octave by an Soft LFO within pattern measures, lets say with a
"frequency" of 2 bars at a tempo of 132, then the stepping of an 8bit
modulation (256 steps!) won't be really audible. So the same soft-LFO
resolved with 12Bit (=4096 steps) will be satisfying also for a LFO
duration of 16 bars.
If you do the same modulation to a VCO without rythm instruments in the
background. The stepping of 8 Bit with a 2 bar duration will be audible
at the VCO. You will require 12Bits.
But now: If the modulation destination is not the VCO but the VCF cutoff
frequency, then the same modulation will be satisfying completely. If
the destination is a VCA and the audio signal is a sine, you will
definitley hear so called zipper noises. If the audio signal in the VCA
is a saw, you won't realize any digital modulation noise.
So you see: whether a digitally created modulation source is good or
not, depends completely on the usage of this modulation. I am sure, we
will find examples, where a 16-Bit Modulation won't be good enough! In
these cases we have to use slewlimiters - thats what they are for.
> am i correct that the mcv4, for example, won't let you send any kind of
> controller message out of any or all outputs why these limitations of
> only certain kinds of midi messages on certain channels
The limitation is mostly based on the userinterface. Technically it
would not be difficult on the D/A side, but it requires a very expensive
userinterface (Display, alphadial,...) to handle this.
So the concept for a low-cost interface must be a fix one.
Florian