Phase 90 R28 mod problem

[Errant Tiger]

This is probably wicked rudimentary and I’m anticipating much embarrassment when a solution is revealed, but here goes... I finally decided to do the R28 mod, and managed to find it and clip it pretty quickly (my very first mod, I want to point out). Got everything reassembled and plugged it in... and nothing. Well, not nothing - a warm filtery kind of tone but no actual phasing. The knob just doesn’t seem to do anything. What am I missing?

Thanks in advance...

[MechaGodzilla]

i would clip r28 out completely (or encase it in tape or something) just to make sure it isn't shorting. the way it's sticking up like that, it's looking for something to short on!

[eatyourguitar]

This is probably wicked rudimentary and I’m anticipating much embarrassment when a solution is revealed, but here goes... I finally decided to do the R28 mod, and managed to find it and clip it pretty quickly (my very first mod, I want to point out). Got everything reassembled and plugged it in... and nothing. Well, not nothing - a warm filtery kind of tone but no actual phasing. The knob just doesn’t seem to do anything. What am I missing?

Thanks in advance...

this IS phasing. you just don't have that exaggerated phase 90 sound. maybe you need a balance trim pot to balance the wet and the dry. when they are at unity gain, you will get maximum phase canceling sounds. you can also play with increasing the amount of LFO modulation through changing the LFO amplitude, impedance to modulate, and parallel resistors on the FET's.

[Errant Tiger]

This is probably wicked rudimentary and I’m anticipating much embarrassment when a solution is revealed, but here goes... I finally decided to do the R28 mod, and managed to find it and clip it pretty quickly (my very first mod, I want to point out). Got everything reassembled and plugged it in... and nothing. Well, not nothing - a warm filtery kind of tone but no actual phasing. The knob just doesn’t seem to do anything. What am I missing?

Thanks in advance...

this IS phasing. you just don't have that exaggerated phase 90 sound. maybe you need a balance trim pot to balance the wet and the dry. when they are at unity gain, you will get maximum phase canceling sounds. you can also play with increasing the amount of LFO modulation through changing the LFO amplitude, impedance to modulate, and parallel resistors on the FET's.

Right. I guess maybe a better way to put it is that the knob just doesn't work. Full CCW and CW sound exactly the same.

[Errant Tiger]

i would clip r28 out completely (or encase it in tape or something) just to make sure it isn't shorting. the way it's sticking up like that, it's looking for something to short on!

Sadly, this did nothing. I then realized that there’s a trumpet at the top of the board that everyone says don’t fuck with. So I fucked with it and got it to make some deeper phasing noises when I crank it CW, but the actual rate knob continues to be useless.

I’m going to find a position for the pot that is closest to the depth I most seriously need and leave it there until I can figure something out, or take it to my local shop. Which is 40 minutes away. Gig next week might have to be phaseless...

ETA: except I just snapped the thingy connecting the switch to the rest of the board. Dammit. I was not meant to mod...

[eatyourguitar]

maybe you clipped the LFO?! hence no modulation. what revision number is printed on that PCB? R28 on that PCB could be a different resistor than R28 on some other version PCB. if you had no modulation or no oscillation in the LFO then that would all make sense. that trumpet (trim pot?) is probably dry wet balance. so the wet signal is out of phase with the dry output but just not modulated by anything.

[Errant Tiger]

maybe you clipped the LFO?! hence no modulation. what revision number is printed on that PCB? R28 on that PCB could be a different resistor than R28 on some other version PCB. if you had no modulation or no oscillation in the LFO then that would all make sense. that trumpet (trim pot?) is probably dry wet balance. so the wet signal is out of phase with the dry output but just not modulated by anything.

It's Revision F, I think? Red board. I compared it to a couple pics over and over and when I clipped it out I saw that it was in fact R28.

Of course, it's irrelevant now since I snapped off the footswitch connector. Trying to decide if it's worth it to pay someone to fix it, or just suck it up and buy a script reissue, which is the sound I was going for with the mod. They're cheap, as pedals go, but cash is tight.

[MechaGodzilla]

the whirlwind phaser is really good too, not too expensive secondhand

[Errant Tiger]

the whirlwind phaser is really good too, not too expensive secondhand

That's what I hear; thanks for the tip! I'm definitely intrigued, but I have a pretty strong sentimental/iconic attachment to the look of the MXR. Silly, I know, but what can you do? (Other than get over it).

[Bartimaeus]

Step 1: buy whirlwind phasor second-hand
Step 2: rehouse whirlwind into the enclosure of your broken phase90

[Errant Tiger]

Step 1: buy whirlwind phasor second-hand
Step 2: rehouse whirlwind into the enclosure of your broken phase90

I like it.

Does the Whirlwind sound more block-ish or more script-ish?

[MechaGodzilla]

i don't have any real experience with the different mxr models but the whirlwind just destroyed any of the mxrs in demos (to my ears anyway). i would say it sounds more 70s than 80s.

i think i prefer phase 100 to phase 90, but the whirlwind - limited as it is - just sounds great