Amps out of phase...

[Glenn Fricker]

Hey all,

Got an interesting one here: When reamping, I've noticed how my 5150 & Recto are exactly 180 degrees out of phase. Question is, how the hell do I tell which one is right? I know the easiest solution is a reversed speaker cable, no big deal, I have one... but I want to make sure I'm plugging it into the right amp....

TIA,
-0z-

 

[ahjteam]

Hey all,

Got an interesting one here: When reamping, I've noticed how my 5150 & Recto are exactly 180 degrees out of phase. Question is, how the hell do I tell which one is right? I know the easiest solution is a reversed speaker cable, no big deal, I have one... but I want to make sure I'm plugging it into the right amp....

TIA,
-0z-

I'm not entirely sure, but it shouldn't matter which one you flip, because if you flip the other one, they should be in the same phase, right? Same thing with eg. top&bottom mic on snare, it doesn't matter which one you flip the phase on. Also you can do the phase flipping for the mics, right?

 

[HeadCrusher]

^that's what I thought too. curious to find out what's the problem...

 

[Glenn Fricker]

I'm more worried about the speakers moving in the right direction... yes, it can effect your sound.

 

[Katau]

Are you using the same cabinet with both amps? IOW, is the amp out of phase, or the cabinet out of phase? If it's the cabinet, then just rewire it. If it's the amp...? Never heard of that before.

 

[Metaltastic]

Oops, nevermind...

Maybe take your other amps (Windsor, Traynor, I dunno if you have any others), record with them, and go with the majority phase?

 

[ReliXKeepeR]

Why don't you just compare it with the DI signal?

 

[Keiffer]

yeah, I've seen the same. One has an additional/less inverting stage.

 

[LSD-Studio]

right?
there is no "right"? or actually they're both right.

when you're using different tracks it doesn't matter anyway, when you're blending for the same DI just flip the phase on one of them, it really doesn't matter.
The speaker is still movin in the correct direction (just T/2 "later")

 

[Glenn Fricker]

right?
there is no "right"? or actually they're both right.

when you're using different tracks it doesn't matter anyway, when you're blending for the same DI just flip the phase on one of them, it really doesn't matter.
The speaker is still movin in the correct direction (just T/2 "later")

Yeah, you're probably right.


BTW, I said "amps" not "Cabinet" it's the same cab.

 

[xconnyx]

some day, while recording both amps at the same time, i found out that my engl powerball and peavey xxx are 180degres out of phase too. i switched phase at the desk, because bothe cabs were isolated form each other.

i think there is no right phase with guitaramps/cabs. its just the thing that, if there are two cabs or two amps running the same signal at the same time, have to be in-phase.

 

[AdamWathan]

You should try splitting the guitar signal between both amps and running them into a stereo cab simultaneously... I bet THAT would sound weird

 

[Loren Littlejohn]

I'm more worried about the speakers moving in the right direction... yes, it can effect your sound.

Grab a speaker cable and put a 9v battery across the end. The cab with the speakers that shoot out and stay that way is the one you don't want to change.

EDIT: never-mind I'm stupid.

 

[53Crëw]

This might be what Keiffer was mentioning.....

If the two amps don't have an equal number of gain stages they may not end up in phase at the speaker.

I seem to remember that each time a signal goes through a gain stage in the amp, the phase is inverted 180-degrees. So if one amp has 5 gain stages and the other amp has 6 gain stages, the two outputs would be 180-degrees out of phase with each other.

The simplest thing to do is just use a "crossover" speaker cable that will reverse the polarity of one of the outputs to the cab.

 

[Keiffer]

it's been a while but if memory serves my DR and either 5150 or Rev1 do not reamp the same. for the same DI one is inverted to the other... all else equal. checking the schematics and stages were different. although this is not a guarantee.

 

[daveotero]

I'm not entirely sure, but it shouldn't matter which one you flip, because if you flip the other one, they should be in the same phase, right? Same thing with eg. top&bottom mic on snare, it doesn't matter which one you flip the phase on. Also you can do the phase flipping for the mics, right?

Not true for snare. If you flip phase on your top mic your snare is more likely to be out of phase with the OHs, HH, or toms.

In Oz's case, I would just flip phase at the pre or in the DAW.