The practical side of this one was performed and documented a couple months back, but since i've had this back-log to work through, the text is only getting written now. But good things come to those who wait, right? Or so i've heard...
Regardless, i couldn't not grab this deal when i saw it. A shure 55SH "Elvis mic", with allegedly low(ered) output, for 75eu shipped (considering it retails around 160-ish). Now, granted, i HAD peeked around the interwebs beforehand, and it seemed that, at least in some cases, the on/off switch could be a suspect. But on the other hand, even IF the capsule itself turned out to be a dud, i could still MacGyver another capsule in there, one way or another (possibly from a Grundig GDSM-202, but shhhhh!...). Aesthetically it was in good shape, so why not?
A quick test upon unpacking revealed that the output was so low, that it wasn't there anymore at all. But since i already had a prime suspect in mind, i proceeded with disassembly of the switch compartment. Removing two screws was all it took.
As it turned out though, it wasn't the switch. Oh well, onwards and upwards... Somewhat literally, even. The front (just about) half of the mic body itself comes off upon removing four screws, revealing a more or less familiar(?) sight.
From what i had read, this may or may not be a capsule virtually identical to the one in the SM57 and/or SM58, and it does look a lot like the latter (once you remove the headbasket), but we digress.
Once another four screws are removed, the capsule mount / housing is freed. I can't quite say whether the enclosure behind the capsule has much of an acoustic effect (perhaps something with the lower frequencies?) or not, but at the very least, i'd say it blocks out some of the higher frequencies from behind. But i'm just speculating...
Time to open up said enclosure, then. On a side-note, this can't even be too-too old - the internal foam windscreen wasn't even particularly dirty or anything. So far, so good, eh?
That gets us to the back of the capsule. The rubber surround acting as a shockmount is quite visible, between the capsule and the aluminium ring.
For a little while, i wondered what the yellow Mylar tape might be doing there, but then the brainfart cleared, upon closer inspection. Those are there to pretty much shield the more-than-hair-thin wires coming from the capsule's voice coil. And there was the issue, as it turned out.
If the previous photo didn't reveal it, here's a closer look. Yup, one of the wires had broken off the solder pad, and was stuck to the adhesive on the Mylar tape. This took a wee bit of creativity, but...
First of all, since the wire from the voice coil was now a smidge shorter than it used to be, and in order to avoid needing to stretch it to reach the main solder pad, i figured i'd just "extend" the solder pad. A piece of used solder-wick and few seconds later, the pad was extended, and the wire resoldered. A quick DC resistance measurement confirmed that there no longer was an open circuit between the two big solder eyelets.
Post-reassembly, some quick tap-tests confirmed the success of the repair. Hooray for a cheap "classic"!
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