Build Your Own Clone Message Board

My Phase Royal build suffered from what, based on this forum, seems to be a common problem: a loud pop from the foot switch. I tried pull-down resistors of various values in various configurations to no avail, tried switching the power source, reflowing the joints, etc. I finally realized that I should check for the other common source of popping: the LED. Sure enough, after I de-soldered the wire off lug 1 the pop disappeared completely. In order to fix the pop without taking the LED out of the circuit, I soldered a .47 uf cap from the lug 1 (LED) to lug 2 (gnd), my quick and dirty version of the resistor-cap delay circuit suggested here: http://www.muzique.com/lab/led.htm. I'm using a much smaller cap value than he recommends, and didn't add a second resistor to the 4.7K R38 already in the circuit, but it seems to work fine. Absolutely no pop.

I hope this helps those who, like me, were frustrated that this great-sounding pedal was rendered almost unusable by the switch pop.

- Kilgore

Hey kilgore, love your handle!!! Welcome to the forum, and thanks for the post!

Kilgore,

Right ON! Thank you for this post. I, too, have been suffering from popping on my phase royal, and will set about seeing if I can fix it using the method you proscribed. I don't suppose you managed to snap any pics...?

If not can you answer me this question? When you reference Lugs 1 and 2, are those references per the BYOC instructions?

Thanks again!

CEW

Yes, lugs 1 and 2 per the BYOC instructions: the upper left and middle left. Good luck.

- Kilgore

I've encountered this popping problem with the Phase Royale and the first thing I tried was removing the wire from lug 1 on the footswitch to remove the status LED from the circuit. The pop was still there though. What gives?
B.

I've encountered leaky input or output caps that caused switch pop in the past. Check for small amounts of DC on foot switch lugs 4 and 8 in both states. If you find voltage, try replacing the associated cap (C1/C12). Shouldn't happen with the the bleeder resistors in place (R1/R29), but it seems to happen anyway sometimes.

You can also try removing the wire from lug 4, and then lug 8, to see which one is the culprit and work from there.

Are you seeing this a lot in the PR? Mine is quiet.

I have another finished and same thing so, it's 2 in a row so far that I've noticed. I shall follow your lead and reply with my findings.
I sincerely appreciate the help
B.

I just applied KilgoreTrout's mod to my Phase Royale and Optical Compressor and it seems to have eliminated the problem (though I was playing them last night rather quiet - tonight they will get the full practice volume test).

Thanks for chiming in Morgan - I'll keep this handy for the next time the issue appears (if).

Thanks Kilgore!

CEW

I tried the cap across lugs 1 and 2 as suggested above. Pop still there. Then I tried wirng up a seperate LED as suggested on the Muzique link but using the Phasers switch and power. Pop gone, yay! So then I mod the circuit to reflect the mock up I had just successfully tested and the pop returns!
More investigating showed that an aligator clip directly from the switch to the LED worked fine, no pop, but using the PCB trace that runs to the LED from the switch and the pop comes back. WTF?
B.

Maybe a PCB layout issue? I remember I used to need to do this on the old digital delay boards (not use the pcb mounted LED resistor), but didn't have that issue on other builds that used the same circuit.

That's what I'm wondering too.
B.

The final fix came down to this last night. I pulled the current limiting resistor from the board and put it in line with the wire going to lug 2 on the switch. I was going to put a jumper in its place but used a 390ohm resistor instead. This has drastically reduced the pop. All other suggestions did not work as well as this.
B.

So, 390r in place of the current limiting resistor, and 4.7K between lug 2 and pcb pad 2?

Yup. The 390ohm resistor is not a must, it just happened to be easier and handier. The customer picked it up last night and was pleased with the resuslts. I was pleased to liberate my work area of another repair/project
B.