so, if you have a dc coupled interface but are confused by the cable issue, this might help. if anything i post is off, let me know.
so as you know, normal stereo cables wont work as outlines in the manual. See below...
so, to buy premade cables of awesomeness, there are two choices i'm aware of...In general special cables are recommended when using a DC-coupled audio interface as a source of CVs. Most audio interfaces have balanced outputs (on TRS ('stereo') jacks or XLRs), while synth CV inputs are unbalanced (usually on TS ('mono') jacks or minijacks). If you use a regular stereo or mono jack lead, you'll be shorting out one of the balanced output signals (usually the R (ring) to the S (shield)). While this probably wouldn't be a problem for normal audio use, when outputting the sustained voltages that are useful as CVs you risk damaging the interface hardware.
The usual recommendation is to make up special cables with a TRS jack at one end and a TS at the other, connecting T->T (tip to tip) and S->S (shield to shield) while leaving the R (ring) floating i.e. unconnected.
An alternative is to wire a TRS jack to two TS jacks, connecting one T->T/S->S and the other R->T/S->S. This then gives you two copies of the output CV, one of them inverted, which is particularly useful from LFOs. Note that this cable configuration is identical to that of a regular "Y" audio insert lead.
http://www.slygoosecables.com/index.php ... t&Itemid=2
and the always great ad infinitum
alex does make these special on request( you need to email him) but as of now(sept 2011..for all you in the future wigglers) he's swamped so it will take a hot minute.
EDIT by os:
Expert Sleepers now offer pre-made floating ring cables too:
insert cables are a good choice
they look like this
and you can find more info here
you can get these anywhere, but you can peep the link to read more about the cables if you like. of course, the eurorack massive needs 1/8 not 1/4. evidently, any 1/4 to 1/8 adaptor will work, either mono or stereo. they look like this....
coupler also found this solution. Although this box is getting harder to find.
Rean NYS-SSR-8 1/4" Patch Box 8 Send/Return Modules ($35 - G)
8ch TRS cable snake
16 1/4" to 1/8" adapters from monoprice (0.50 each) edit: you need STEREO (trs) adapters to make this work with the patch box
The Patch Box is meant for send/return on mixers, which basically means it takes TRS in on one side and spits out TS and RS on the other for each input. You just run the snake from your interface into this box, and then you don't need any special cables made just for silent way. Those 1/4"-1/8" adapters are super cheap on Monoprice, so just get 16 of those and put them all in the TS/TR outputs and then you can just use your normal modular cables to connect to the box. Or if you use a larger format modular then you obviously don't need the adapters...
Rean is a company recently launched by Neutrik, so the quality is pretty nice. I can attest that based on handling this little box, it probably will probably hold up nicely. It's pretty heavy and feels very sturdy. I'm very happy that I randomly found this little magic box. I haven't been able to find anything else like it.
if your a crafty sort, you can make your own.
Ring Floating Method (probably what you want if CV is involved)
Tip -> Tip
Ring -> Nothing
Shield -> Shield
okay, that's all i got. Hopefully this helps. if i said something wrong or if you have any additional info, please chime in.