AB/Y buffered splitter with phase reverse switches

[Diablo]

Anyone know of a stomp box kit out there to take one guitar signal and split it to one or two buffered outputs, with the option of phase reversal on either output? I see that RG Keen has some schematics, but I'm dumber than a box of rocks when it comes to solid state electronics. I can build a kit if it has a layout, schematic and all the right parts. I'm kind of a paint by numbers guy when it comes to stomp boxes.

[soundguruman]

Maybe you could get the Morley AB switch, and mod it with phase switches.

[Diablo]

Unfortunately, the Morley is a passive box, and I believe I need an active circuit with buffers and two transformers for ground isolation.

[Chuck H]

Why do you need this? Many guitars have pickup selections that can flip the phase as do some stomp boxes so that you can never know for certain what your phase is! Do you plan on running two boards simultaneously from one guitar? I'm just interested in what you're trying to do.

[soundguruman]

I understand why he would want phase reverse.
It's actually a standing problem, but most guitar players don't understand the problem exists.

The phase reverse on the Pick Up does not address the actual problem.
The PU should remain in humbucking mode, despite the phase reverse.
The phase switch on a guitar reverses only one coil - and turns off the humbucking mode. So, that is not a solution.

WHAT a guitar player REALLY wants: Adjustable phase, to set the phase lag anywhere from 0-180 degrees out of phase or in, or anywhere in-between, at any point.
Except, there is no such device (yet).
But now you know you want one, even if it's never been invented for guitar amps.
Yes, that would be very handy.

[pdf64]

'Adjustable phase, to set the phase lag anywhere from 0-180 degrees out of phase or in, or anywhere in-between, at any point'
Such as phase lag is surely dependent on frequency?
My understanding is that the issue is signal polarity, which can be inverted easily.
Pete

[eschertron]

Adjustable phase, to set the phase lag anywhere from 0-180 degrees out of phase or in, or anywhere in-between, at any point.

Isn't that what the various BBE devices claim to do?

[Diablo]

What I am trying to do is run a single guitar to two different amps that may or may not be in phase with each other, or a single guitar to two channels of the same amp that may or may not be in phase with each other. I think it needs to be buffered so I don't change the tone because of the impedance. And I need the two isolation transformers to isolate the two amps so I don't get a ground loop hum.

[Chuck H]

Well, this next suggestion won't do anything for ground loops, but...

There is probably a DI box, EQ or other such device in your possession right now that inverts phase just by virtue of being in the signal path. Set the device for unity everything and place it at the end of one of your pedal boards. Then if the two legs are out of phase you can just activate the added device to correct. Something to try until you get your custom box built.

As to SGM's observation about being able to control phase... I'm aware of why it's useful, but I'm also aware of the fact that it doesn't really come up that often and sometimes there is an alternative solution. But thanks. There are a couple of scenarios where a player might want to simply invert phase. One is Diablo's current situation. Another could be when a player wants to run an effect in parallel. For example: I've read that some players have run their wha pedals parallel to the dry signal to reduce the intensity of the effect and that this can result in an out of phase situation (for better or worse). As to having 180* control??? I think that's a brilliant idea and I'm going to say why. Acoustic feedback control!!! Whether you want to accentuate or eliminate it from any stage position. Many times I've seen players try to eliminate feedback only to end up with badly hacked EQ for their instrument or, just as bad, try to get the right feedback effect that they can do in some venues but seemingly not others. As much of a consistent problem as both of these situations present I have never seen a 180* phase control device that should help. And I would design it and run straight to the patent office if I weren't such a stringently moral fellow. Because if it doesn't exist yet a patent for a phase control device to help control acoustic feedback for musicians could do very well once it caught on. SGM should get to work on it for two reasons. I want to own one (of course I may just build my own) and I'm not inclined to sit on the notion for TOO long

[Jazz P Bass]

Not too sure why you 'want' a buffered splitter.

Now you have 'colorization' issues.

I would go with a ToneBone Bigshot.

Radial BigShot ABY true bypass AB-Y switcher

[Diablo]

Not too sure why you 'want' a buffered splitter.

Now you have 'colorization' issues.

I would go with a ToneBone Bigshot.

Radial BigShot ABY true bypass AB-Y switcher

Here's the reason I think I need a buffered splitter. I'd like to avoid tone coloration, but I also need phase reversal between the two outputs. I don't think there's any way to do that passively. Reading up on RG Keen's interweb thoughts on the subject has me convinced that the best way to do this is to use opamps to buffer and 1:1 isolation transformers on the outputs to prevent ground hum.

[Jazz P Bass]

Have you read the BigShot desriptor?

Channel A: straight out.

Channel B: transformer isolated from Ch A, phase reversal as compared to Ch A, ground lift.

[g1]

What Jazz suggested above sounds like exactly what you are looking for.
If you are going to use isolation transformers, then that is all you need to invert the phase for one side.
That is the passive method for phase inversion.

[Jazz P Bass]

The SwitchBone is a buffered splitter.

Tonebone Switchbone - introduction

[Diablo]

OK, I found what I was looking for, and it's a kit.
It does require a minor modification to add the phase reverse switch on one side, but I also found instructions on how to do that on the BYOC forum.

Amp Selector And Stereo FX Router DIY Guitar Effects Pedal Kit | BYOC