A/B/C Switch

[MarkR2955]

A local studio that I have made some pedals for is asking about an A/B/C Switch - similar to the Morley Tripler. I can find the schematic for one, but still being somewhat of a noob I have trouble with schematic to layout. The pedal would need to be A and/or B and/or C - Can anyone offer some suggestions?

[Al Heeley]

Here's some I did earlier:

Passive Switch Wiring
9V battery powers the LED indicators thru a 2k resistor
Uses combinations of 3PDT and DPDT switches
X-grounding for noise suppression where appropriate
Where not indicated, jackplug earths are grounded out together

1. A/B switch allows switching between 2 inputs into one output (eg: switch between 2 guitars in a gig without having to unplug) or use in reverse with one input switching between 2 outputs, eg: 1 guitar into either of 2 amps or amp/tuner, or select pedal chain or bypass for example.

2. A/B/Y switch allows AND/OR config: one guitar into either amp A OR amp B OR both at same time.
Note: Can be used in reverse as A/B box but not recommended for 2 inputs simultaneously into one amp - guitars will interfere and cause hum.

3. A/B+X/Y switch allows A or B choice on input and X or Y choice on output, for example, choose one of 2 guitars on stage into one of 2 different amps, 1 of 2 guitars into either amp or tuner (will mute amp)

4. A/B/C switch allows one of 3 guitars into 1 amp or in reverse, 1 input into either of 2 amps or a tuner for example. Switch 1 chooses between A and (B or C). Switch 2 chooses either B or C.

5. Feedback/Loop switch selects to either bypass or route signal thru an effects box with option to blend some of the 'wet' signal back into the effect loop (level set by 250k pot) or leave it 'one-pass'.

[trixdropd]

I'd use transformer isolation to avoid ground loops like the morley tripler has. geofex has a great write up on this.

[MarkR2955]

How would I be able to have a b & c all on at the same time?

[Processaurus]

How would I be able to have a b & c all on at the same time?

That would be a different switch.  Probably more intuitive, as the A/B OR C and  B/C isn't very natural.  That would just be a switch that alternately muted the inputs of three amps or connected them to the input.  You would just alternately connect each amp send to either the instrument input or to ground.

[MarkR2955]

I know Morley makes one called the Tripler, and Kendrick Amps makes one...I can find a schematic for the morley one, but am too dumb to get from schematic to pedal...