Pulldown resistors in parallel

[armdnrdy]

I noticed something that I left out of the Mutron Flanger MN3007 circuit and was wondering if someone could offer some insight.

The original circuit bypasses the effect by making a connection from the output of the input buffer through a non polar 10µf cap, and a 47K pull down resistor to the switch.

*Note the 47K pull down resistor between the switch and the output jack.

Original output section:



I deleted the original "bypass" components and added the other half of a 3PDT switch at the input for true bypass.

Modified bypass circuit:



My question is:
In the original, the 47K (R38) is seen in parallel with another 47K whether in bypass of effect mode which results in the output seeing a 23.5K pull down.

Having a 47K to ground on your bypassed signal isn't exactly true bypass.
I thought to replace R37 with a 24K and call it good but, I was wondering, is the 47K (R38) serving a purpose? (anti pop)

Suggestions always welcome.

[R.G.]

I wouldn't sweat it. The exact value of R37 is probably not an issue. You could use anything between 10K and 1M, most likely, unless the pedal has other unusual issues.

It is **possible** that the original pulldowns were solving some other problem, such as capacitive transfer from the clocking circuits, where having a lower value of pulldown helped lower the transfer of clock to the signal line. I'd leave R37 at 47K.

As to R38, I'd leave it out until testing proves it's needed. There's some rationale for it in the case of a buffered switch like the original, but I don't think it's needed in this case, unless testing shows that too much clock noise gets into the signal bypass wiring. In that case, I'd shield the bypass wiring rather than loading down the bypass signal with resistance.

[armdnrdy]

Thanks R.G.

Great insight as always!