[sdiy] RE: Reaktor and CV

[WeAreAs1 at aol.com]

"James R. Coplin" <moog at qwest.net> wrote:

<<  Does anybody make a A->D converter that could be stuck onto TDIF 
or light pipe which would be DC-coupled? If so there could really be the 
makings of an impressive digital analog hybrid. I'm already extremely 
pleased with the results of outputting reactor to my Serge and 2600 to 
create some really nice FM type stuff which would be nearly impossible 
otherwise.  >>

James,

You could probably pick up a used original ADAT for next to nothing - 
especially if it has a broken or malfunctioning tape transport (there may be a few of 
those out there... ;)  )  I see fully working ADAT's for sale all the time 
for less than $300; broken ones for as little as $100.  You'd even get some cool 
input level indicators with the ADAT's bar graph level meters.

It would then be a matter of modifying the ADAT inputs to be DC-coupled 
(simply bypass the coupling capacitors).  The ADAT I/O circuitry is all located on 
one easy to access circuit board, so it's likely that you could do this 
without needing the ADAT schematics, but they are available if you really need to 
see them.  You could also DC-couple the outputs and gain another eight analog 
outs via the lightpipe connection from your 2408.  BTW, early (Black Face) 
ADAT's have 16-bit converters; ADAT XT's (silver face) have 18-bit converters -- 
but I think the 16-bit conversion would work just fine for this purpose.

Michael Bacich

P.S. -- If there is a slight DC offset in the ADAT input circuitry (after 
DC-coupling), you could probably simply trim it out inside Reaktor, which, I am 
assuming, has some kind of virtual "DC offset" trimmer modules.  This would 
simplify the ADAT modification process.