Just got around to listening to these.Greg_L wrote: ↑Mon Nov 11, 2019 4:25 pm @rayc and anyone else that might give shit.
This is the difference between PRE phase inverter master volume, and POST phase inverter master volume on Plexi/Bassman type amps that don't have their own master volumes.
Gibson Les Paul Traditional - Muttbucker PAF bridge
Marshall 1987 50w Plexi
Presence - 4
Bass - 5
Mid - 6
Treb - 4
Bright channel 1 vol - 5
High input only
Marshall 1960B 4x12 - Celestion G12-65
MXL R144 on axis, 3" off grill, dead center - Shure SM57 on axis, 3" off grill, just outside dustcap
50/50 mic blend
No FX or EQ
First up, the amp in it's natural state. No master volume.
1987 full.mp3
Turned down 50% with POST phase inverter master volume.
1987 POST PIMV 50%.mp3
Turned down 50% with PRE phase inverter master volume
1987 PRE PIMV 50%.mp3
This is without adjusting the mic preamps. Full loud is the baseline, and the others are relative to full loud. As you can tell, the amount of volume reduction between pre and post master volumes is different. And so is what it does to the tone. By cutting the signal before the phase inverter, it loses a lot of grind. The phase inverter, as part of the power section, obviously plays a big part in the tone. If I cut it back even further/quieter, the tone thins out even more. The preamp section alone is not enough to get the goods from this amp. Putting the master volume as POST phase inverter, we still get that goodness from the phase inverter being overdriven by the preamp, and the sound is closer to stock.....just at a lower volume.
Really like the no master vol. clip. This one is by far the best for me.
The 2nd one isn't that different to the first but I found it a bit too bright/harsh - similar to the first one, but harder on the ear!
The 3rd one - much lower gain and well bright! I didn't like listening to that one much - but then I do have a bit of a headache.
