Stereo Ampifier?

[cdemike]

I'm not sure I understand the design goal. Are you after a wet/dry rig with one side doing reverb and the other dry signal? If the goal is reverb-only on one side rather than reverb mixed with the "original" guitar signal, I think that's only possible with two separate channels, whether that's using two amps or a stereo amp. If the goal is dispersion of sound over a physical space, a stereo head into two separate cabinets might be best to minimize headaches with needing several outlets, more cables, frustrations with levels/apparent volumes, etc.

Sorry if it's off-base, but it seems to me that based on the question about separate phase splitters you may be after a setup that takes a mono input and splits it into two separate outputs that can be fed to two separate cabinets placed apart from each other for a spatial stereo effect. If that's the case, I would approach it as one preamp feeding parallel output sections either with two phase inverters or two single-ended output sections. The PI mixer setup in the 18Watt.com schematic seems to me to work in reverse of what you're aiming for if you want two separate and different signals fed to different places.

Splitting a mono signal is a dual mono arrangement by definition until some sort of stereo field effect is introduced, like a stereo reverb or a stereo oscillator, like a tremolo or Leslie effect. If I just split a preamp output into parallel output stages with separate cabs, that's dual mono output, not stereo. Both cabs would be sending out the same signal, so a RIGHT/RIGHT output, or however you want to call it. The SPACE YOU"RE PLAYING IN AND HEARING would create a stereo impression, but not the ampifier itself. I was envisioning the use of FX loops in each channel to receive an actual stereo reverb effect so that each cab would then have a Right Wet and a Left Wet output signal respectively. The amp itself doesn't seem to be able to render a stereo image. Right? That's what I asked, is there such thing as a stereo guitar amp in the first place?

The idea of stereo guitars, for instance, seems to be a misnomer (no offense). It's like dual half mono output, right? Like I'm sending half the strings to one ring of a TRS jack, and the other strings to the tip. That's not stereo! Maybe I'm overthinking this. But do you get what I mean? Put any amp in a room and the ROOM is stereo. What makes the AMP stereo???? Just trying to proverbially shroom out the possibilities in my head.

No offense taken. This makes much more sense than what I was speculating -- should sound really cool! If you're aiming to have the stereo effect primarily come from the effects loops, it seems simplest to me to just split the signal after the last preamp gain stage into two parallel loops with each having its own driver, maintaining separation of the signals.

Good point. So then parallel SE output stages from each side of a PI tube would then cancel each other out. Right? Sh!tballs.

Swap the phase of the speaker coming out of one?

I chuckled at this -- reminds me of that anecdote about the Soviet space program using pencils in lieu of fancy pens that work in microgravity environments like NASA (as it happens, the Soviet space program did end up pens -- the same pens as NASA! https://www.scientificamerican.com/arti ... nasa-spen/).

If you're considering single-ended, why not just run two separate output sections after the recovery? An option to keep it push-pull would be to just run two whole separate output sections with each having its own phase inverter and therefore maintaining channel separation. If you ran the effects loop recovery into a dual triode set up as two separate concertina PIs, you'd have no net gain in tubes vs a design with a LTPI.