[Mark Brown]

Hi all, the time is here to make an amp selector switch and I am wondering if this idea might work....

Meth addict picture aside, A) controls the guitar inputs TO the amps so Red/Yellow/Blue respective. The B) connection is the Speaker side. Now, if a fellow were to tie the grounds for speaker and signal together would that work?? That is essentially how they are represented inside of an amplifier, but I don't know if it would work on a switch.

I am trying to make a selector for 3 amp heads to run into the TAE. Logic says it makes sense this way.... but I am sure there is something flawed.

 

[Mark Brown]

In the absence of advice (which i might have ignored anyway) I went ahead and gave it a go. Works like magic.

I'm not good at drawing things, but here is a flow chart of how it works. I put a 1/4 inch input jack on the switch, tied its ground common to the "speaker" which in this case is the input for the TAE. Amp grounds get tied in input and output and voila. 3 way selector rotary dial to select between Amp heads and input at the turn of a dial.

I think the finished product will need some finesse... but the prototype is working!

 

[Verne]

I have no idea what it is, but it looks impressive to me. Certainly far more technical than what I am capable of. Nice work Mark.

 

[Mark Brown]

Thanks Mr. Verne. It is mostly the same as the design found in a simple guitar selector switch, the difference here is I am using it to send signal from the Amplifier outputs to the TAE and the signal from the guitar to the amp heads.

The part I was unfamiliar with was how the grounding path was going to interact being directly tied where it was. Turns out it works just dandy. That's a benefit because I was wondering how many switches it was going to take to split all kinds of crazy signals. You can buy these types of things, but making one for 8 dollars seems to make sense to me.

Building the amp rack serves no purpose if I have to constantly be playing with wires. I have built a 4" hollow channel/shelf into my desk so I can install a plate into it and have a guitar input jack, the selector switch and then add an output jack and a switch that controls that. Then, when the mood suits me, I can go from the amp heads direct to cab. Right now the TAE is routed through my interface and headphones so there is no need to have a speaker hooked to that, but it is nice sometimes to simply play the amp heads through a cab the way they were designed to. That will be super easy to do as it is simply a DPDT switch, send the signal one way to a cab and the other to the TAE.

The only drawback of this is if I am a complete moron and select the wrong amp, the failsafe is that without input there is no output so the transformer should be ok. That isn't a theory I want to test if I can help it, but it should not be hard to remember to select which amp I am using. One has to turn them on, so it isn't much more of a step to select them I wouldn't imagine.

 

[alwaysflat]

Interesting. Ponder perhaps, that if you have shorting inputs to your amp, leaving a cable plugged, not connected, removes the short, and may increase the noise floor of that amp left powered on. May or may not be a factor.

 

[Mark Brown]

I only have one input filled per amp so I don't think it should matter? It didn't seem to matter last night when I gave it the old college try.

They are unloaded selectors so my comfort level leaving amps powered on and not selected is right around zero.

The amps have no common connection between them. Amp A B C all have separate connections for their respective ground before they make the connection on the switch and then share ground to output.... if that makes any sense. I'm not sure it does