Patchbox for pedalboard

[sherminator1995]

I'm thinking of making a patchbox for my pedalboard, so I don't have to constantly feed cables through the gaps to get to pedals. Basically, it's going to have ports for

(1) From Guitar
(2) To Amp Front
(3) From FX Loop Send
(4) To FX Loop Return

Now, this is super simple to setup, I know, but I have one feature which I'd like to implement into it. Basically, sound only goes through (2) and (4) when there is something plugged into it, otherwise it bypasses them and goes and on to the pedals. I've illustrated this in the following image:



I have a feeling this could be done using a stereo jack (maybe a similar principle to how Boss pedals only switch on when something is plugged into the jacks).

Could someone help me out with this?

P.S.: Yes, I know I could use a patch cable and jump the two when I'm not using an fx loop, but that's boring.

[blackieNYC]

http://www.mouser.com/ProductDetail/Switchcraft/113BX/?qs=iwvYsH9bSFYjgIvXzY1hDA%3D%3D#spec

the switchcraft 113BX  - checkout the pdf data sheet, look at model 2A.
the tip is connected to an extra pin, but this pair is pushed apart by the insertion of a plug.

[GGBB]

With two of the jacks blackieNYC recommends, you can do that easily. But I got to thinking about whether or not you could get fancy and clever and do this so that the amp-in jack can be left always connected to the amp, and you don't have to move the cable from amp-in to fx-return jack when you want to have no loop. You'd just unplug both fx loop cables and you're in business. Turns out you can, but it's not a standard Switchcraft jack - it's a custom one they make for Mesa Boogie (and maybe others) - part number 610130. It's a tip-closed isolated-make - diagram XI here: http://www.switchcraft.com/Documents/Jack_Schematics.pdf. One of those for the fx-send, and a 113BX (or 12A open style) for the fx-return (which is diagram III). The shunts on those are connected to the amp-in jack and the pre-amp loop return jack (the pedal side of the amp-in jack). The connection between the amp-in jack and the pre-amp loop return jack goes through the extra isolated-make switch on the fx-send jack so that that connection is broken when no cable is plugged in.

That would be extra cool - if you can get a hold of one of those jacks which are probably 2-3 times the price of one of the others.

[sherminator1995]

http://www.mouser.com/ProductDetail/Switchcraft/113BX/?qs=iwvYsH9bSFYjgIvXzY1hDA%3D%3D#spec

the switchcraft 113BX  - checkout the pdf data sheet, look at model 2A.
the tip is connected to an extra pin, but this pair is pushed apart by the insertion of a plug.

So, the circuitry options aren't different versions of the same thing, they're just different ways you can wire it up?

How would I wire up a pair of these in that case? Run a jumper from the tip shunt of one to the tip shunt of the other?

[blackieNYC]

GGBB is quite right - you don't want your signal path to be fuzz, reverb, fx return (power amp input). You want the amp's regular input. I'd like to help, but I really don't understand what the jack contact #3 is doing.  GG?
what I think is that you have to have a fixed cable going to the amp input, of course. when you plug a cable in to the fx return/power amp in, you want:
1. the fuzz goes to the amp in.
2. the reverb goes to the fx return.
3. the send is active.
Both the send and return cables will be unplugged at the same time of course, otherwise you won't get the4 whole signal chain. So it seems both send and return jacks can be used for switching.
So the insertion of a cable into the jacks you designate for the fx send and return must switch fuzz to amp in, and reverb out to fx return.
The removal of a cable from the jacks you designate for the fx send and return must switch fuzz to reverb in, and reverb out to amp in

Note that the little box between pins 2 and 3 is an insulator. When the jack is inserted, 1 and 2 are pushed together, 3 and 4 are pushed apart.
Does this look like it will work?  I think so.

[GGBB]

That drawing looks right to me - I'll check more thoroughly when I have time later this afternoon. It "looks" like the chain goes out to the fx return but because of the shunt it goes back to the amp input when the fx return is unplugged - so that's right.

[blackieNYC]

But I cannot find that jack GGBB linked to - drawing XI.  Better track it down thru mesa boogie I guess.  Sound like its worth doing.
the jack will have a clear plastic insulator that can let an inserted plug close a circuit without actually connecting the plug in that circuit.
this isn't it, but this is the idea here:
https://www.emma-music.com/-switchcraft,us,4,SWI-E003M-13.cfm

[GGBB]

But I cannot find that jack GGBB linked to - drawing XI.  Better track it down thru mesa boogie I guess.  Sound like its worth doing.
the jack will have a clear plastic insulator that can let an inserted plug close a circuit without actually connecting the plug in that circuit.
this isn't it, but this is the idea here:
https://www.emma-music.com/-switchcraft,us,4,SWI-E003M-13.cfm

Right - I couldn't find that jack on the Switchcraft site either, but I found mention of it in an amp forum: http://ampgarage.com/forum/viewtopic.php?t=23734&sid=113a014c4df0b82600c7eed34435cbd6#p287428. Do a search for "mesa boogie 610130." It is available online but only for Germany, Austria and Hungary: http://www.meinlshop.de/en/mesa-boogie/spare-parts/electronic-components/sockets/jack-swcrft-610130#description. Otherwise you'd have to order it from a MB service dealer or maybe call them directly. It's the input jack in a few boogie amps including the King Snake.

[GGBB]

Apparently Neutrik makes a jack that *could* be used - it's an NMJ6HCD2-RM: http://www.neutrik.com/zoolu-website/media/download/2804/Jack+Circuits. You'd have to modify it to wrap some heatshrink around the ring connector so the the "ring make" becomes an isolated make. Also - it's pc pins not lugs - don't know if they have a lug version - but this might be easier to find than the boogie jack - and cheaper.