dead metal muff lead to an interesting mod

[pinkjimiphoton]

first jfet, a buffer between input and output was dead. was smd, so i didn't even mess with it. instead, i just disconnected the buffer completely. not only brought the circuit back to life, but to my ears, improved the tone and dynamics substantially.

its really easy to disconnect if you want the buffer gone, or if everything on the pedal audibly "works" but passes very little or no output signal <including in bypass, which is always buffered stock>

open her up, and look near the input jack. you'll see a little blob labeled fb1.... ferite bead one.

take the side opposite the input jack, and tack a wire on that side. make the wire about 2-2.5" long.

snip the first lead of the bypass ribbon cable, first as in top to bottom with the switches facing at you.
this would be lead #7 on the switching board on the bypass switch.

solder the lead from the ferite bead to pin #3 of the footswitch.

done. now it should work, if it didn't, and the buffer is out of the picture. in my case, it was shorted and it killed the whole pedal.

if ya really feel the need, heat up the 10k smd resistor just above/to the right of the ferite bead. that will effectively isolate the buffer completely, but its likely overkill. i didn't even bother, as it wasn't passing signal anyways.. but removing that resistor will remove the input to the buffer completely.

to my ears, it has better dynamics, less squash and more balls, too. ymmv.

anyways..... if ya don't like the mod, just unsolder the wire from fb1 and reconnect pin 7 to the switching breakout board.

done deal!

[bool]

Hmmmmm...

Out of sheer impulse I looked up the m/muff schem on the forbidden place and saw that the input jfet is biased with a 1meg resistor from the 4.5V.

This would make a perfect opportunity for a BJT buffer mod!

Since practically all SOT23 smd packages share the control-out-in electrode layout, it would be theoretically possible to swap a smd BJT or a mosfet right in.

You would just have to remove the fet (MMBF4393 ?) and solder a BJT or a MOSFET directly in its place.

Suitable candidates would be the smd equivalents of 2N2222, BC549C and a 2N7000, which are MMBT2222, BC849C and a 2N7002.

One thing with a BJT is the whole circuit could become a little noisier, but would at the same time retain a better attack and mid-focus (not tested with a metal muff in particular, but a general observation).

[bool]

Oh, one thing more - if you mod for a BJT, you should perhaps also change the 10K resistor (R55) after ferrite bead to a 1K (like in most other BJT buffers).

And in place of the R59 you could solder in a 100pF (or something) smd cap as a RFI filter.

[pinkjimiphoton]

i had toyed with replacing the jfet bro,
but i didn't want the buffer anyways, its always on... so i just 86'd it. the whole pedal seemed to come to life more. but i agree, you could easy get the old smd out and graft in a thru hole component.
too lazy to try it at this point...
right now trying to bring a mutron phasor II circuit back from the shades