owlexifry
Well-known member
- Build Rating
- 5.00 star(s)
despite my doubts that this would sound any good, i was still keen to build one and see how it goes.
haven’t seen/heard many demos of the migfet on youtube, not sure what to expect.
the board calls for a 125B, but i really wanted to have all the knobs inline, so i made it happen in a 1590BB2.
measured a few mmbf5457 jfets and selected x3 that rated around -1.5V (Vp) and ~3 ma idss
for setting bias, had a look at the data in the build doc and a thread on here, tried some stuff, idk didn’t really seem to make sense or sound good.
tried setting all x3 trimmers at roughly halfway, still too much gain / overdrive.
so i just did it all by ear to try and get it to a nice tone that would clean up enough at low gain settings.
once i had this set right, hot damn, it actually sounds pretty good.
still way more overdrive than i expected this thing to be capable of, unless i just haven’t biased it correctly, but idk, sounds good enough to me.
surprisingly the barebones chargepump circuit/supply doesn’t make any noise. it doesn’t even have a 100u or 47u filter cap in front of it. nice.
in this demo, running an epiphone explorer direct into figment preamp then straight into normal channel (bright off, crunch off) SLO-100 clone build
i reckon it would probably sound better with either single coils, or a treble booster, tight drive or something similar.
still yet to try it direct into FX return, will see how that goes. bit scared to though, cos the output is super loud.
in front of an amp, unity seems to be around 9o’clock. 12o’clock is monster. don’t wanna know what dimed is like
didn’t get time to try boosting it with a nice tight drive just yet, but i reckon it’ll probably love it.
haven’t seen/heard many demos of the migfet on youtube, not sure what to expect.
the board calls for a 125B, but i really wanted to have all the knobs inline, so i made it happen in a 1590BB2.

measured a few mmbf5457 jfets and selected x3 that rated around -1.5V (Vp) and ~3 ma idss

for setting bias, had a look at the data in the build doc and a thread on here, tried some stuff, idk didn’t really seem to make sense or sound good.
tried setting all x3 trimmers at roughly halfway, still too much gain / overdrive.
so i just did it all by ear to try and get it to a nice tone that would clean up enough at low gain settings.
once i had this set right, hot damn, it actually sounds pretty good.
still way more overdrive than i expected this thing to be capable of, unless i just haven’t biased it correctly, but idk, sounds good enough to me.
surprisingly the barebones chargepump circuit/supply doesn’t make any noise. it doesn’t even have a 100u or 47u filter cap in front of it. nice.
in this demo, running an epiphone explorer direct into figment preamp then straight into normal channel (bright off, crunch off) SLO-100 clone build
i reckon it would probably sound better with either single coils, or a treble booster, tight drive or something similar.
still yet to try it direct into FX return, will see how that goes. bit scared to though, cos the output is super loud.
in front of an amp, unity seems to be around 9o’clock. 12o’clock is monster. don’t wanna know what dimed is like

didn’t get time to try boosting it with a nice tight drive just yet, but i reckon it’ll probably love it.

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