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guitar 4 way foot switch

how do l build a foot switch with a single input (from guitar) to 4 separate jack outputs? Only one of the outputs can be on at any time. Each output in the unit must have an LED to indicate what one is active.  Diagrams would be helpful .... thanks  :-)





Picture of guitar 4 way foot switch
robertpool (author) 3 years ago
thanks for that. Below is the current set up. Any advice on improving the signal flow would be appreciated.

AB Box Setup.jpg
Yep, that's a pretty complex way of doing what you want. Have you looked into any commercial switchers, like this Joyo device?

Here's a schematic for a guitar splitter, uses a tl074 quad opamp. Before I mentioned grounding the input--that's wrong, I was thinking of a mixer, not a splitter. Grounding each opamp output is the way to go here.

In it's simplest form, a foot switch on each output would ground the unwanted signal paths. But to select one exclusively, you'd need to stomp twice. But it would have the benefit selecting more than one path simultaneously. For more "automatic" selection of one path, some logic circuit would be needed--maybe with FET transistors acting as the "switch to ground."

Note that in your diagram you also mix the signals after the FX, but I assume that part already works OK.
gmoon3 years ago
So many ways to achieve this, but unfortunately none are really simple. 

Check out RG Keen's Geofex page on FX stuff, the section on "Signal Routing and Effects Order." The "Juggler" is a good link. It uses an CMOS analog multiplexer (basically an analog switch) to select an output. Some of the other links there use audio transformers to truly isolate the signals and avoid any ground-loop hum.

There are other ways to do it other than CMOS--even using relays is possible, but that would probably pop quite a bit with an audio signal. And you'd still need some type of simple logic circuit to select only one output, think Boolean logic here. A binary counter, some type of exclusive OR made of discrete chips or even a tiny multicontroller.

I'd be tempted to make a splitter with a quad opamp, then mute the the unwanted outputs with an optoisolator on the opamp inputs (ground those inputs)....would still need some type of logic to make it a single output only...