Stereo Amps - how to retain stereo imaging in front of two amps?

[Brian Wahl]

Hello all - I've got a technical question...

I'm having some strange behavior with stereo amps. I typically put wet effects (always stereo) after the amp/cab block, but in some presets I have some in front of them.

In these situations, I have a stereo delay that ping pongs (that's the delay right in front of the amp blocks), and then two amps - one panned hard L and the other hard R - and then a cab block set up with two cabs - again one panned L and one R.

I hear the stereo imaging of the amps no problem, but the delay gets summed to mono when the amps are engaged. If I turn the amps off, it's back to stereo. This tells me that the cab block isn't doing it - it's the amp(s).

Anybody know why this is? Or how to retain stereo effect imaging when going into two amps that are set up in stereo like this?

I've attached a file of a very simple preset that shows this. If you turn the amps off, the delay bounces between L and R. Turn them on and it's mono.

I've got my outputs set to stereo, using out 1.

 

[Greg Ferguson]

Amp blocks sum stereo signals to mono. Continue panning the amp blocks hard left and right, but change the input select setting of the left amp to left, and vice versa.

From the amp block page in the Wiki...

INPUT SELECT​

(Owners Manual) "The Amp block processes audio in mono. This control determines how incoming stereo signals will be processed. You can input only “LEFT” or “RIGHT” channels, or “SUM L+R” (the default setting)."

Adjust this to make two Amp blocks handle each side of a stereo signal separately. Or when using a single preset with two guitars, each with its own Amp block (Axe-Fx only). Or to keep the stereo spread of a stereo delay placed before the Amp blocks.

 

[Brian Wahl]

Amp blocks sum stereo signals to mono. Either put your effect in parallel to the amps and set its level to 100%, or move it after the amp blocks.

Thanks. So there is no way to have a stereo effect going into two amps (in parallel, panned hard L/R) and have the stereo imaging retained? I understand that running a stereo effect into a single amp block would sum to mono, but this preset is running the stereo effect into two separate amp blocks, and they're panned.

 

[Brian Wahl]

OK - FIXED .

In the ideal tab, you have to have your Left amp's input set to Left, and the Right amp's input set to Right (rather than Sum L+R)

 

[∞Fractals]

The manual is full of help (like he posted for you).

Glad you got it sorted.

 

[javajunkie]

OK - FIXED .

In the ideal tab, you have to have your Left amp's input set to Left, and the Right amp's input set to Right (rather than Sum L+R)

Yep, and just an FYI you can do that with many mono effects and stereo too. Drives, Volume, Cab blocks, Reverb, and quite a few more.

 

[Admin M@]

Hi @Brian Wahl

When you set a preset up like this, don't forget to also change that setting on all of the other channels in each amp block. Also set their balance controls wide, of course.

 

[javajunkie]

Hi @Brian Wahl

When you set a preset up like this, don't forget to also change that setting on all of the other channels in each amp block. Also set their balance controls wide, of course.

Yeah, I've forgot that one before.