MV or no MV that is the question

[Capt Vemo]

Not really a complete newbie but I figured this is the best place to ask this question. I have a plexi replica with the Lar/Mar MV installed in it. The amp sounds great but my friend brought it to my attention instead of have a MV in the head I would get way more of the original superlead tone from the amp if I removed it and used a distortion pedal. He mention that once a MV is installed it makes the amp sound really thin. I miss quoted my friend what I was kind of looking for is I play mostly at bedroom volumes so would the amp sound better with the Lar/Mar PPIMV. Or remove it and use a good distortion pedal in front of the amp? Also I think this is in the wrong section I think it should be in the mod and restoration section. Is there any way a moderator can move it?

[neikeel]

A PPIMV drives the phase inverter tube, so that is where the distortion occurs, the output valves are given an easy ride by the PPIMV as most of the signal is shunted away from them. Thin tone with PPIMV will be due to a poor PI valve and the fact that if you turn it down too much you simply do not move as much air and you lose speaker distortion too.

If you just use a pedal you will always be using the pedal tone, not necessarily the power valves only turning the amp volume knobs up will do that. So your friend is not strictly correct .

Only way to get power valves cooking at sensible volumes is to use an attenuator. I am a big fan of the Alex version.

No need to remove the LAr/Mar type PPIMV anyway - turn it up fully and it is out of circuit.

Best results are with attenuator one click (-3 or 4 dB) and the PPIMV at about 8/10 on the dial IMO.

[Janglin_Jack]

Best results are with attenuator one click (-3 or 4 dB) and the PPIMV at about 8/10 on the dial IMO.

+1 to this.

Mike