Author Topic: ts9 noiseless switching making noise?  (Read 2921 times)

aab0mb

ts9 noiseless switching making noise?
« on: September 21, 2013, 07:45:34 PM »
I have a ts9 that i've just finished modding a little bit. All seems to be working well although there is an audible 'click" from the switch when the pedal is turned off. 

I have a few other tubescreamers sitting around so i tried a few to compare.  i have some that are totally silent in the switching and some that have a slight click.  The one i'm referring to has a click that's quite a bit louder than any of the others.

I speculated that it clicks because it's a rather new switch or that the increased gain via the mods has somehow contributed to a noise during switching.

Has anyone experienced this with a supposedly "noiseless" switch?

I'm at a loss here.  Any info, experience, or ideas would help. 

Thanks gang.

psychedelicfish

Re: ts9 noiseless switching making noise?
« Reply #1 on: September 21, 2013, 08:00:44 PM »
There are half a million threads on switch popping on here, I suggest you read a few. If you can't find any (you're probably at least half blind) do a search for Lbzg and you'll find several.
If at first you don't succeed... use bigger transistors!

aab0mb

Re: ts9 noiseless switching making noise?
« Reply #2 on: September 21, 2013, 08:18:50 PM »
Aren't all of those threads (that i've seen with mine working eyes) about true bypass mechanical popping?

This seems like a rather different issue all together...


aab0mb

Re: ts9 noiseless switching making noise?
« Reply #3 on: September 21, 2013, 08:35:05 PM »
"for non-mechanical switches the switch elements may couple a little of their control signal into the signal path. This is what happens with JFET, CMOS and relay bypass switches. If any of these are driven with a sudden-change control voltage, the unavoidable capacitances inside them can couple the fast wavefront into the signal lines, and this makes a pop. "

and the suggested fix:

"Ramp the control voltage up/down slowly (over a mS or two) to keep it from being coupled through the small capacitances."

ANyone know how to go about the fix part?

psychedelicfish

Re: ts9 noiseless switching making noise?
« Reply #4 on: September 21, 2013, 08:46:51 PM »
Aren't all of those threads (that i've seen with mine working eyes) about true bypass mechanical popping?
Sorry, your first post made me think you were talking about some kind of mechanical switch, a "noiseless switch" being a particular brand you'd bought

I still have no idea about what sort of switch you're using, perhaps you could link some kind of schematic? As for ramping the control voltage, stick a capacitor to ground from your control voltage. Some of the information in the threads about mechanical popping is still relevant, are you sure there's no caps that end up with a floating end when you change the state of the switch? Is there any DC across your switch?
If at first you don't succeed... use bigger transistors!

R.G.

Re: ts9 noiseless switching making noise?
« Reply #5 on: September 21, 2013, 08:48:38 PM »
If it's a commercial TS with the original switching scheme used, not an optimistically "modded" one, see:
http://geofex.com/Article_Folders/bosstech.pdf
for how it works. Note especially Rslow and Cslow.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

aab0mb

Re: ts9 noiseless switching making noise?
« Reply #6 on: September 22, 2013, 01:18:41 AM »
ok there is a small dc voltage across the switch.  That explains why it kind of sounds like a static pop.  I'm kind of trying to trace and look at the schematic here but it's not my strong point. Any pointers in the right direction from out in pedal land?

aab0mb

Re: ts9 noiseless switching making noise?
« Reply #7 on: September 22, 2013, 01:57:04 AM »
ok there is a small dc voltage across the switch.  That explains why it kind of sounds like a static pop.  I'm kind of trying to trace and look at the schematic here but it's not my strong point. Any pointers in the right direction from out in pedal land?

Yeah, apparently Ibanez didn't think that both Cslow caps where needed on that particular day.  I was looking all over for the pair of caps and could only find one.  After tracing I found an open spot where the other cap should have been placed.  Dropped the part in... no more pop. 

Thanks for chiming in guys.  I realize the last thing this forum needs is another ts9 and or switch pop thread....   :icon_rolleyes:

duck_arse

Re: ts9 noiseless switching making noise?
« Reply #8 on: September 22, 2013, 12:09:32 PM »
.... but you have now provided another possible cause/effect/solution we can use next time it comes up. we'll just refer them to you.
"You've got a suss sus sus sus sus sus sus suspect device."

“Unless you are living in a cave, you know what it means," he said.

aab0mb

Re: ts9 noiseless switching making noise?
« Reply #9 on: September 22, 2013, 07:16:38 PM »
Ha!  great! 

Yeah it's nice to find a problem and take care of it as well as having it documented for others if needed. 

R.G. saved the day on this one.  No thanks to the Ibanez factory for leaving out parts.... :icon_mad: