Nick's Tone Bender is broken -- please help!

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Nick
The Artist Formerly Known As nightraven
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Nick's Tone Bender is broken -- please help!

Post by Nick »

Hi all,

My fucked up, corroded, beer-stained Tone Bender is behaving really strangely and I can't seem to figure out what's causing it -- would any of the tinkerers here happen to have any suggestions of things to try?

When I first plugged into it, it sounded wimpy and raspy and just all-round awful. After opening it up and measuring voltages etc, however, it started to work properly and it sounded ace. This seemed to last for a couple of weeks, but sure enough, eventually it went back to its same old weak sizzle.

The Tone Bender remained in this sorry state until I bravely tried to open the pedal up again to poke around inside. I kept the guitar plugged in during the course of doing so (NB: dismantling a MKI is particularly awful when the paintjob is as fragile as this) and it didn't take long before the fuzz started to work again. In fact, all it took was removing the four screws, and gently prising the top half of the enclosure away from the black base.

Image

^ Like, this is really all that it took to get the pedal to work again. The two halves aren't even fully separated, and yet it was such a simple solution to this annoying issue. I'm reluctant to put the pedal back together again until I can figure out exactly what the problem was, because the problem is bound to happen again. Please help me!
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daCod
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Re: Nick's Tone Bender is broken -- please help!

Post by daCod »

Inappropriate touching be my bet… 😋
if you're ever in the shit, grab my tit
i like pedals when you know they're on
When I saw you with that lost look on your face saying you had just saw ET, I thought "uh oh, game over" - innerflight
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Nick
The Artist Formerly Known As nightraven
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Re: Nick's Tone Bender is broken -- please help!

Post by Nick »

daCod wrote: Tue Nov 09, 2021 2:32 am Inappropriate touching be my bet… 😋
Don't pretend that you didn't get intimate with Jim's when you had the chance :whistle:
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daCod
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Re: Nick's Tone Bender is broken -- please help!

Post by daCod »

Nick wrote: Tue Nov 09, 2021 2:42 am
daCod wrote: Tue Nov 09, 2021 2:32 am Inappropriate touching be my bet… 😋
Don't pretend that you didn't get intimate with Jim's when you had the chance :whistle:
B1CF812D-B088-42DF-AEB5-261775F72D00.gif
B1CF812D-B088-42DF-AEB5-261775F72D00.gif (5.09 MiB) Viewed 1429 times
if you're ever in the shit, grab my tit
i like pedals when you know they're on
When I saw you with that lost look on your face saying you had just saw ET, I thought "uh oh, game over" - innerflight
(\__/)
(='.'=)
(")_(")
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Doc Holliday
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Re: Nick's Tone Bender is broken -- please help!

Post by Doc Holliday »

Could it be a fragile wire?
Or a poor connection?
If it’s not receiving it’s full 9V or has a bad connection maybe this is why it sounds awful.
Tbh I have a similar problem regularly with my George L cables on my pedal board 😏
A faulty cable can cause pedals to operate weekly until I poke it or lift the pedal up and suddenly it all kicks in. Just needed a wiggle.
Long term prob needs a new cable.
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simonm
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Re: Nick's Tone Bender is broken -- please help!

Post by simonm »

Could be a cold solder joint - are there any joints that are conspicuously matt rather than shiny?
Also, because there's no support for the board other than the ptp wiring, it's not held in place and it could be that it's being pushed down slightly onto the back of one of the pots and partially grounding out when you close the case? You could try putting a bit of paper over the backs of the pots just as a test to see if that helps.
Handmade, high-impact, great-looking radical queer germanium fuzz. A different approach to 1960s-inspired fuzz pedals, no clones, check them out at https://goodfuzzysounds.com or on YouTube https://tinyurl.com/GFS-YT
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phidias
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Re: Nick's Tone Bender is broken -- please help!

Post by phidias »

Something silly but, have you tried changing the battery? I have experienced strange behaviours in some of my MKI and Zonks with batteries that measured fine but, for whatever reason, don't work well on those pedals (but do on others), making them sizzle and been unstable. A simple and quick thing to check.
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Nick
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Re: Nick's Tone Bender is broken -- please help!

Post by Nick »

I tried gently moving the wiring about (incl. the battery terminals, where at some point a previous owner has soldered new wires onto existing ones, presumably to replace the PP4's), but I wasn't able to reproduce the issue. It doesn't seem like the wiring would have even had a chance to move much when I got the thing to work yesterday -- really all I did was just remove the screws, and wrench the top of the case away from the bottom by a matter of millimetres.

The MKI has a kind of 'sheet' of insulating paper between the board and the pots already, but even so, I tried very gently pushing the board towards the pots and didn't hear any signs of issues.
One would think that the old bean left enough clearance between the board and the exposed metal input socket, but even so, when I experimented with shorting out the adjacent parts on the board with the jack socket, the results were much worse than just a wimpy weak fuzz :badteeth: so I'm ruling out that as the cause for the issue as well.

It doesn't appear to be (at least directly) an issue with the way that the two halves of the enclosures ground the circuit, because I conveniently have video evidence of the pedal working while the whole thing was fastened together. I'm able to get a good fuzz sound out of it at present both when the two halves of the enclosure are separated, and also when I use my hand to 'biologically' ground them (the only difference is that when the two halves are in contact, there's less background hum).

The battery was a good call. I've changed out the battery, and I've even mounted it the other way around, but I'd like to recreate the problem before (literally) closing this case.

I'm thinking about undoing the jack sockets and repositioning them, but that's further down the list of options for now, only because of the risk of damaging what's left of the paintwork :paranoid:
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HorseyBoy
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Re: Nick's Tone Bender is broken -- please help!

Post by HorseyBoy »

Could one of the caps be faulty/on the way out?
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Philip
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Re: Nick's Tone Bender is broken -- please help!

Post by Philip »

Sounds like it's needs some Aberdeen air. 👍🏼
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