mbb (shorting) vs bbm (non-shorting) switches (mod-wah dual inductor pcb)

[kirk10x]

As I prepare to for my first project, I was baffled by a bit of advice. Specifically, I have a GGG Mod-Wah pcb and am collecting components to rebuild a Vox 847 with those new innards. For switches, the advice provided was break-before-make switches, together with added resistors to minimize the popping when switching in use. I am a novice here, but that seems backwards to me. Wouldn't the make-before-break (shorting) switch eliminate the pops by providing an unbroken signal path?

Btw, I would welcome advise for rotary switches suitable for this build. So many models in Mouser have HUGE decks.

Thank you,
Kirk

[thermionix]

What are you switching?  If it's caps that could have DC stored, it may still pop with MBB.  The resistors would bleed off the stored voltage.

BUT...if this is something you're unlikely to ever switch in the middle of a song, it probably doesn't matter much.

[kirk10x]

What are you switching?  If it's caps that could have DC stored, it may still pop with MBB.  The resistors would bleed off the stored voltage.
BUT...if this is something you're unlikely to ever switch in the middle of a song, it probably doesn't matter much.

This design switches two things:

• capacitors,
• inductors

Not planning to switch anything during a song, but I am simply concerned for my speakers.

[thermionix]

It's probably not an actual threat to your speakers.  As jarring as a loud amplified pop can be, it generally isn't really any louder than your normal guitar signal.  The power of your amplifier is still a limiting factor.  Also the brevity of it means it doesn't have much chance to heat your voice coil.

But I understand wanting to avoid the noise.  You're probably on the right track thinking about MBB, it might be enough to keep the popping minimized without adding resistors.  I don't know why BBM would be recommended, I can't think of anything that might be damaged by briefly having two selections shorted while switching.  But there could be some reason I just haven't thought of.