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Simple Patch Panel Question

  1. Aug 12, 2010 #1
    I have an old telephone switchboard with standard 1/4'' TRS connectors that I am planning to rewire for use with my many many many guitar effect pedals and recorders and things. The switchboard has 4 panels, each panel has two rows of 26 jacks.

    Let the 'o' be jacks and the '|' symbols are not there they are just imaginary to help group what I plan to do. I was planning on wiring the panel like this:

    [ 1 2 3 4 5
    [ o o | o o o | o o | o o o | o o o o o ....
    [ o o | o o o | o o | o o o | o o o o o ....

    IN1 | OUT1 | IN2 | OUT2 | etc ....

    so that the first four jacks (columns 1 and 2) have six outputs (columns 3 4 5) and this process will be repeated for the next group of 5 columns until there is a single column which I am not going to worry about. These in/out groups will all be separate from one another.

    Now these are simple normally closed jacks with only the signal and ground leads. How exactly do I wire this? At first I assumed that I wire all the outs in series and all the ins in series and then throw a diode in there connecting the ins and outs. But then I realized that after a couple of gain stages I will get some wicked distortion from that diode and I need my audio fidelity.

    Maybe I am just over-thinking this. Any help guys? I desire to learn!
  2. jcsd
  3. Aug 12, 2010 #2
    First I would put all the IN's in the top row, with their partner OUT's below them. That's the way I've wired studio panels anyway. Then, since you don't seem to have normal-switched jacks, just wire each box to its own set of IN/OUT jacks. Then you can use patch cables to build up a series of effects. If you had "normaled" jacks, which have a connection for a signal that is broken when you plug something in, you could wire the panel to have a "normal" connection, say each box in a series OUT to next-IN. Then you could dispense with all the patch cords until you wanted to change something.

    I would also wire some sets of jacks together so you can split a signal to go to more than one input. To combine outputs you should use a mixer, rather than just plugging them together. You could make a _very_ simple mixer with a group of pots and resistors and put them on the panel too. Getting too fancy? Don't forget to wire you telephone to a jack so you can record off of it...heh...
  4. Aug 12, 2010 #3
    Excellent information! Thanks a whole bunch. Yeah I realized I was probably trying to do something that did not make a whole lot of sense, especially since I don't have those nifty switch jacks. I asked one of my Physics professors and he basically said the same thing. I came to report the news in case anyone else was interested but I saw that you replied all too swift.

    I did actually make a simple mixer and excellent that you say wire my telephone to one of the jacks because that was one of my first recording projects. Hands down telephone mouthpieces make some of the coolest microphones, like the Coachwhips does it:

    Another quick question since you have done some studio stuff, would I have say a single patch panel devoted to the series of say a bunch of 4 jack fan-outs and then have another panel devoted to the one in (top) to one out (bottom) setup? I am merely interested in practical studio setup.
    Last edited by a moderator: Sep 25, 2014
  5. Aug 12, 2010 #4
    Also, what wire (gage/solid or stranded) do you normally use to connect these? I was just using like 20 gage stranded audio wire. I'm sure it doesn't matter, just curious.
  6. Aug 12, 2010 #5
    If you have patch panel strips to spare, by all means use a separate one for the multi's. IIRC there's about 25 jacks across a 19" rack, if you've got more than 10 effects boxes you're going pretty crazy...

    Any wire will do. Not much current flowing. And most outputs are very low impedance, they won't have trouble with noise so shielding is not really required...
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