from: http://reviews.harmony-central.com/reviews/Effects/product/MXR/Phase+90+Mod/10/1
" This is the part of the review that really matters for this pedal. The standard reissure Phase 90 sounds fairly nice - a nice airy-fairy phase that's quite solid in it's tone. Unfortunately it tends to clip in the midrange of its phase cycle...when you're aiming for airy-fairy cleans, this can be a problem!
I went about doing a couple of mods to this pedal. The R28 mod where you just remove a resistor from the signal (see previous poster for sound review there), and the C11 and C12 mod, which just involves the removal of 2 capacitors from the signal path. These are the input and output caps (as far as I can tell, I don't know much more about electronics than basic understanding of a schematic). When you remove these, it gives the effect more headroom, which means you can hit the effect really hard with your guitar signal, and it shouldn't clip at all now (or at least, very little).
And that's exactly what happened - I now have a Phase 90 that has around 80% of its distortion gone! I just pulled out some pliers and clipped one leg off the resistor and each of the caps and bent them away enough so they wouldn't touch the board. This way, if I decided I don't like it I can just solder it back together
.
So here's how to do it:
R28 - Just above the output jack, its the first resistor there, runs east-west across the board, and is slightly offset from its brothers above it. Just clip the outside leg.
C11 - This is located on the top, right-hand side of the board. It runs north-south up and down the board. It's right on the edge of the board, and it's between the input jack and another, bigger capacitor.
C12 - Is on the lower, left-hand side of the board. Just below the output jack is a series of 3 resistors...C12 sits just next to the last one, and it runs east-west across the board. It's sort of between the output jack and the footswitch."
" This is the part of the review that really matters for this pedal. The standard reissure Phase 90 sounds fairly nice - a nice airy-fairy phase that's quite solid in it's tone. Unfortunately it tends to clip in the midrange of its phase cycle...when you're aiming for airy-fairy cleans, this can be a problem!
I went about doing a couple of mods to this pedal. The R28 mod where you just remove a resistor from the signal (see previous poster for sound review there), and the C11 and C12 mod, which just involves the removal of 2 capacitors from the signal path. These are the input and output caps (as far as I can tell, I don't know much more about electronics than basic understanding of a schematic). When you remove these, it gives the effect more headroom, which means you can hit the effect really hard with your guitar signal, and it shouldn't clip at all now (or at least, very little).
And that's exactly what happened - I now have a Phase 90 that has around 80% of its distortion gone! I just pulled out some pliers and clipped one leg off the resistor and each of the caps and bent them away enough so they wouldn't touch the board. This way, if I decided I don't like it I can just solder it back together
.So here's how to do it:
R28 - Just above the output jack, its the first resistor there, runs east-west across the board, and is slightly offset from its brothers above it. Just clip the outside leg.
C11 - This is located on the top, right-hand side of the board. It runs north-south up and down the board. It's right on the edge of the board, and it's between the input jack and another, bigger capacitor.
C12 - Is on the lower, left-hand side of the board. Just below the output jack is a series of 3 resistors...C12 sits just next to the last one, and it runs east-west across the board. It's sort of between the output jack and the footswitch."
