Patch Cords customized for more functionality

bryan · Joined: May 28, 2008 Posts: 8 Location: some furniture

I need some advice, please.

What passive functions would be feasible for installing on patch cords? This would save rack space and reduce the time it takes to set up patches.

For example (on a eurorack-format modular), is there a good pot that would hold up well and not get in the way when attached to a patch cord? Would an inverting cord be as simple as crossing the +/- wires? What are some ways to get passive filtering and appropriate resistor values? What other things can be done in this vein?

Maybe an even better way to do this would be to use a little custom adapter that you can plug into on the end of a patch cord.

Possibilities, advice and pros/cons about doing this type of thing would be much appreciated.

DrJustice · Posted: Fri May 30, 2008 4:36 pm Post subject:

As you suggest yourself, a pot connected as a voltage divider is a nice attenuator. With a bit of shrink tubing to isolate the pot and secure the wires it ought to stand up to normal use.

Simply crossing the wires is probably not too useful as it would cause signal outputs to be shorted to ground, and ground used a a signal. Using Y-cables (or cables that split into more branches) is usually OK, both for mixing (check with your particular modules!) and for splitting.

Passive filtering is indeed possible. The simplest one would be a 1st order RC filter (a nice little ecalculator here).

A capacitor in series will work as a DC blocker. A diode in series is a half wave rectifier, or use a diode bridge for a fullwave rectifier.

Hmm.. there has to be more...

DJ
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elektro80 · Posted: Fri May 30, 2008 4:46 pm Post subject:

Good advice, but I kinda wonder why you feel you need to move signal processing to the patch cables. Attenuating a signal is signal processing in the modular world. If there is something specific you need then simply stripboard it and hook it up to a panel?

bryan · Joined: May 28, 2008 Posts: 8 Location: some furniture

DJ, thanks much that certainly helps me out.

elektro80, good question. In my case it's for 2 purposes: to conserve space in a compact system, and for live performance - it would be faster to have some dedicated utility cords rather than having to do a separate patch.