Please help with a custom switch problem

[effectsbay]

Hello All

I'm running into a wall with a switch problem I'm having. A friend of mine asked if I could help build a switch for her, and she had some unusual requests, that at the time, I thought would be easy. She plays 3 acoustic based instruments (acoustic guitar, tenor acoustic and banjo). Each will need to have their own line in to the switch. Each will need to have their own line out of the switch (which goes into their own individual DIs). Additionally, the reason for this switch, is that she needs a tuner send/return so all instruments can use the same tuner.

I've basically built this 3 times, and all 3 times, the same problem occurs.. and only when using a mixer. I think it might be something related to Lo to Hi conversion. Basically, if I stick an instrument on 1 you hear it on output 1.. perfect. If I stick an instrument in 2.. you hear it in 2. Good so far, but if you play instrument 1, and jack the gain on the mixer for channel 2, instrument 1 is coming through channel 2. I can't test in my workspace (no PA, no DIs, etc), but I simulated it with amps as channels. I have to gain the hell out of my amp, and I can hear it very quietly in the background... instrument 1 out of 2. So the problem is there, but less noticeable with amps.

This has led me to believe that I jacked up my tuner send/return. I have all channels going to tuner send (as if it was a effect circuit) and all tuner returns are tied to individual tuner returns on the 3PDT switches. I feel that this is the problem, since the return is all ganged up. So, I'm at a loss on what I should do. I feel like my planning is wrong, but I'm unsure how to correct this.

Here is a schematic (hopefully I put it together right). Basically, input goes to ground if the switch is off. When the switch is up, it sends to the tuner and receives output from the tuner, then sends it to the output jack. If it's off, there should be nothing sending to the output.



Here is a diagram of the 3PDT switch



Let me know if you would like to see a gut shot.

This last version I thought I addressed the problem with input going to ground. I thought it was some weird cross talk. The switch was definitely 'cleaner', but the PA/DI problem was still there. It almost sounds like everything comes out on channel 2 when plugged into the PA. Any advise is greatly appreciated. Definitely loosing my mind on this. Something simple.. ugh.

Thanks!
hank

[Tony Forestiere]

Maybe this?

[slacker]

Based on your drawing of the switch I can't see what would be causing it. I'd just ground the unused outputs as well, that should shut it up, if it doesn't you might have some sort of ground wiring problem.

[effectsbay]

Based on your drawing of the switch I can't see what would be causing it. I'd just ground the unused outputs as well, that should shut it up, if it doesn't you might have some sort of ground wiring problem.

Hmmm.. so I'm guessing all I need to do is run a jumper from the middle right lug (output) to bottom center (ground)? I'm really baffled that this seems to work fine with lo-z signal to my amps, but reacts this harshly with PA and DIs. The DIs are powered via phantom, wasn't sure if that was a possible issue as well. It almost acts like a completely different switch with the PA and DIs.

Thanks!
hank