Matthews Guitars
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I've got a really nice 15 amp rated Powerstat autotransformer (variac) that I run my JMP era NMV Marshalls with.
I figured that just for the fun of it I'd compare how they all respond to Variac adjusted line voltage and here's what I've found.
I have very consistent 117 volt wall voltage.
I've found that for EVERY amp I've tried Variac adjusted power with, I always end up around 80 volts to the amp. This is the point where the amp still works
perfectly but its tone gets the most musical changes.
Constant factors with each amp: I compare them all with my Les Paul, and I drive the amps with a Seymour Duncan Pickup Booster, which is a pretty transparent, flat EQ'e line driver and preamp. I set it to about 15 dB of boost which in my opinion is its sweet spot. This gives a faceripping overdrive that still cleans up with guitar volume control manipulation.
Model 2061 20 watt Lead & Bass: This amp is surprisingly fairly stable with regard to tone, but dropping to 80 volts makes it distort much more easily, in fact at this voltage it basically doesn't clean up anymore even at very low volume settings. The tone is otherwise essentially unaffected all the way back up to 120 volts.
Output level doesn't seem to change much, either. I find that there is really little benefit to using a Variac with a 2061.
True (rebuilt) 1969 Plex, 100 watt Superlead model 1959. This amp loses considerable volume output when fed 80 volts. Its tone becomes darker and takes on a very pleasant growl. Seems to accentuate the "woody" character that Plexis are known for. The Variac tames the savage beast, makes it quite tolerable to play
cranked standing in the room with it, and alters the amp's voice in some obvious ways, and in other subtle ways that are hard to pin down. Very much worth doing!
1973 Superlead. A naturally bright and aggressive amp by nature and reputation, and stupendously loud, giving it 80 volts perhaps makes the most difference of any of the amps I've tried with a variac. First, it brings down the volume level by a fair degree. Second, the overdrive character changes more than any other amp. It lose that bright fuzz, and brings out a remarkable clarity to the overdrive in the midrange and treble. Your playing becomes more articulate with greater sensitivity and dynamics. The difference is such that I never want to run this amp without the variac set to 80 volts or so. it just makes the amp so much BETTER. You'd think the amp on the variac had been modded by an amp guru who knows his business, but it's stock.
A good variac unlocks some new tonal possibilities that in my opinion are well worth the reasonable cost of a good used variac. 200 bucks or so.
I figured that just for the fun of it I'd compare how they all respond to Variac adjusted line voltage and here's what I've found.
I have very consistent 117 volt wall voltage.
I've found that for EVERY amp I've tried Variac adjusted power with, I always end up around 80 volts to the amp. This is the point where the amp still works
perfectly but its tone gets the most musical changes.
Constant factors with each amp: I compare them all with my Les Paul, and I drive the amps with a Seymour Duncan Pickup Booster, which is a pretty transparent, flat EQ'e line driver and preamp. I set it to about 15 dB of boost which in my opinion is its sweet spot. This gives a faceripping overdrive that still cleans up with guitar volume control manipulation.
Model 2061 20 watt Lead & Bass: This amp is surprisingly fairly stable with regard to tone, but dropping to 80 volts makes it distort much more easily, in fact at this voltage it basically doesn't clean up anymore even at very low volume settings. The tone is otherwise essentially unaffected all the way back up to 120 volts.
Output level doesn't seem to change much, either. I find that there is really little benefit to using a Variac with a 2061.
True (rebuilt) 1969 Plex, 100 watt Superlead model 1959. This amp loses considerable volume output when fed 80 volts. Its tone becomes darker and takes on a very pleasant growl. Seems to accentuate the "woody" character that Plexis are known for. The Variac tames the savage beast, makes it quite tolerable to play
cranked standing in the room with it, and alters the amp's voice in some obvious ways, and in other subtle ways that are hard to pin down. Very much worth doing!
1973 Superlead. A naturally bright and aggressive amp by nature and reputation, and stupendously loud, giving it 80 volts perhaps makes the most difference of any of the amps I've tried with a variac. First, it brings down the volume level by a fair degree. Second, the overdrive character changes more than any other amp. It lose that bright fuzz, and brings out a remarkable clarity to the overdrive in the midrange and treble. Your playing becomes more articulate with greater sensitivity and dynamics. The difference is such that I never want to run this amp without the variac set to 80 volts or so. it just makes the amp so much BETTER. You'd think the amp on the variac had been modded by an amp guru who knows his business, but it's stock.
A good variac unlocks some new tonal possibilities that in my opinion are well worth the reasonable cost of a good used variac. 200 bucks or so.
