#4 Dunlop Zakk Wylde ZW45 wah pedal teardown & repair

Ok, this one's a real quickie. One of the guitarists in my band got this wah (Dunlop ZW45 Zakk Wylde Cry Baby Wah) as a gift a number of years ago, and in the last few weeks it developed crackly and intermittent sound (regardless of being on or off).

Initial fiddling with the power / input / output jacks pointed towards a questionable patch-cable, but even that soon stopped working, which then turned my suspicions towards cracked solder joints (rather than the jack sockets themselves).

Right then, first impressions. Bottom cover's aluminium sheet, taped to the body. I've been told the mounting screws protruded too far out, preventing the velcro from "sticking". Nice beefy cast body and rocker though - you could definitely... seriously cause some bodily harm with one of these, if need be.


Since the circuitry's as simple as it is, the single-sided board construction is no big surprise, and it's perfectly adequate. "ST0NE" electrolytic capacitors, though. Nope, not "Stone", but "St-zero-ne". The bigger one has a (fake) Rubycon-like vent pattern - that's promising... Also, the same one is an 8mm diameter one (3.5mm lead pitch), shoehorned into a 6.3mm diameter cap footprint (2.5mm lead pitch). Reeeeally "professional", guys...

One MPSA13 and two MPSA18 transistors, a handful of resistors & caps, and "the" inductor. Oh, and the rocker-actuated pot and (SPST) switch, of course. I guess they went with the classic non-true-bypass on this thing (which you can't achieve without at least a DPST switch).

Flipping the PCB over confirms the suspicions. All six of the input jack socket solder joints are cracked, at least partially. I wouldn't put this past the... less-than-ideal mechanical characteristics of the lead-free solder - don't even get me started... But, well, nothing a little of the good-old lead-infused Sn60Pb39Cu1 can't fix. On a better look from other angles, even the DC jack solder joints are... questionable, to say the least. As long as i'm here, i might as well blob some fresh solder onto those too, just in case. And for (extra) peace of mind, the two electrolytics are getting replaced - an Elna RE3 220u/25v, and a Rubycon YXA 4.7u/50v.

Mounting the PCB back, i can notice one further thing - the parts of the case that "meet" with the input and output jacks "feel" a bit like they're at an angle, ie. not completely parallel with the jacks. That, coupled with the mounting screw and jack-socket securing nuts, would seem like it puts some (undue) mechanical stress on the solder joints, right off the bat.

Speaking of mounting the PCB back (and being unable to thread the second jack's collar-nut back in) - they apparently call THIS "deburring", at Dunlop. On a pedal that (still) retails at ~150$. Seriously?

Either way, it's back in one piece, and shall be returned to the owner in the next few days. I expect no further issues, at least not for "some" time.