an a/b pedal that will put the amps in phase

[Fast Pistoleros]

Hello - I am going to run two amps and wondering if there is a box I can make to put the two amps in phase? something like a aby or an ab would work or is it more complicated than this? thank you for your time!

[stallik]

I made a simple switch to swap the polarity of the speaker cables on one amp.

Here's the thing. Some pedals can invert the phase. If you have such a pedal in front of only one amp, you end up out of phase without the effect, in phase with it (or vice versa).
I had this issue and I used the speaker polarity switch to check out what's going on. The difference can be enormous!
Not wanting to have to hit an extra switch every time I engage an effect on one amp only, I just settled on a combination which avoids the issue. Once done, the switch can be done away with though I've left mine in place just to give me another thing to go wrong

[zombiwoof]

Radial Engineering Tone Bone Twin City amp switcher, A/B or both, true bypass, LED's to show which channel your on, and phase reverse switch for phase problems like you are experiencing.  Here's on on Ebay, but try to find one during the big online stores' Holiday sales to get like 15-29% off, or buy mint like new on Ebay like I did and get a real deal:

http://www.ebay.com/itm/Radial-Engineering-Tonebone-Twin-City-Active-ABY-Amp-Switcher-/361702472171?hash=item543725b9eb:g:~zIAAOSwq7JT9QLG

They make a cheaper version with no LED's, but I want to know which amp I'm on so I got the Twin City.

Al

Hello - I am going to run two amps and wondering if there is a box I can make to put the two amps in phase? something like a aby or an ab would work or is it more complicated than this? thank you for your time!