#68 Alesis M1 Active Mk2 rehabilitation, part one

Over on the Badcaps.net forums, a thread was started all the way back in 2010, about power supply issues in these arguably "classic" low-cost active studio monitors. It even ended up being stickied just this winter, so it's been quite active and useful. It served as motivation for myself, to take up hunting for faulty ones - not sure if i had gone through three pairs, but at least two pairs i revived and sold off to a couple friends, some 7-8 years ago, and to this day i've yet to hear back about any further issues, so i take that as a good sign. In the mean time, i still contributed with thoughts and advice there, which helped lead to several successes.

Recently, a fellow forum member there got fed up with his failed attempts to revive his pair of monitors, and got himself a pair of new ones. In that context, we struck a deal for the Alesis'es, and a few weeks later, here they are.

#62 Jamo Sub 200 modding

For background / context: https://mehlau.net/audio/multisub_geddes/

I had been off-and-on "hunting" for a twin, for my Jamo Sub 200 that i bought and revived years ago. Partially for SPL reasons, partially for the multi-sub approach mentioned above, and most recently, for actually sitting my couch on top of the subs.

At long last, a couple months back i finally found one locally, and in matching black finish. And with the 5.1 Jamo speakers it came in a set with, to boot! Those might get reused / repurposed later, (i'm thinking, in a manner similar to one of my previous projects).

#50 Philips HTS7201 Soundhub Home Theater (2.1) teardown & repair

This just came in, with the symptom description of "will no longer turn on". Fair enough, sounds like a power supply issue then. Apparently this retailed around $400-ish when new (according to a 2012 review i found online) - not exactly bottom-of-the-barrel, but it's still very much in the mainstream/consumer range, so i'm expecting crap caps to be the root cause. But time will tell.

#49 Joyo ZoMBie, part two - analysis and repair

It took the best part of an evening and a couple hours the next day, but i managed to lift the schematic for the whole preamp board. I also recreated the board, but that was mostly for sanity-checking. I used all the same component designators, but didn't bother measuring all the dozens of small ceramic caps, because there's only SO far i'm willing to go...

#48 JBL Charge 3 Bluetooth speaker teardown

This JBL Charge 3 came in last week in need of a micro-USB (charging) connector replacement. First thing i did was to look up how to take apart the thing, and the good people at iFixit had a comprehensible enough guide.

The connector board is totally separate from the mainboard, so the "repair" part was trivial, and done within minutes. But the more interesting stuff lies deeper inside. Sure, my photography may never get to be quite as pretty as iFixit's, but on the other hand, you're not here (just) for pretty pictures, are you? You're here to see what makes things tick. Or at least that's the curiosity that drives me to take apart stuff like this.

#47 Joyo ZoMBie guitar amplifier teardown

My bandmate got his hands on this Joyo ZoMBie about a week or two back; it was sold as faulty. No idea how or why, but there's something dicky with the tone control - on some power-ups it works fine, but sometimes quits working (ie. sounds like the setting got stuck at some random point along the travel of the knob), no matter how much you twist it. Power cycling sometimes helps, but inconsistently, and even if it does, it just "gives up" again, sooner or later.

#46 Tivoli Henry Kloss Model One teardown & repair

A client brought in this Tivoli Model One the other day, with symptoms of (lots of) noise. Once again, i went against the mantra of "don't turn it on; take it apaaaah't", but this time, for good reason - the thing isn't mine.

#44 Ram Audio S6000 teardown & repair (rebranded as LD Systems SP 6K)

A good buddy and neighbour of mine had one of his amps kick the bucket in the middle of a gig (one i was helping out on, as well). On the bright side, noone noticed, only when turning-off time came. The beast in question was one of his two LD Systems SP 6K amps (rebadged Ram Audio S6000).

#40 Fake "Beats" Bluetooth speaker teardown & mod

I got this handed in by a local friend the other day. It was apparently bought in Singapore a good few years ago, hasn't been used in quite a while, and i guess(?) the charging cable (slightly less usual mini-USB) got misplaced or something.

#31 Warwick ProFET 5.1 bass amplifier teardown & maintenance

A local buddy just brought this German beastie in, citing a dicky DI output, and an unhealthy-sounding fan. Well, when i say "German", i mean the brand itself; as one might expect, it's "obviously" made in China, as it says on the back. But isn't nearly everything (else), anyway?

#28 Active full-range surround speaker project (BN96-12832 & TPA3118)

Since the "unofficial" theme of this blog seems to be repair, recycling and repurposing (more or less), i finally got around to getting knee-deep into this idea, which i started devising quite a while ago - a pair of "slimline" surround speakers.

Disclaimers:
 - No, these are not meant (or supposed) to be "hi-fi". More just for a bit of "ambient noise", if you will, for movies with 5.1 soundtracks. That, and possibly alternative monitoring for checking mixes.
 - No, these are not meant to go terribly loud. Due to, let's call them, physical constraints, they'll be placed at the corners of my sofa (right up against the wall, opposite the TV and the "mains"), so no huge SPL's are required.

#13 Fisher RS-1022 rehabilitation and bling-ification

So i had this old Fisher RS-1022 Studio Standard stereo receiver brought in, with one of the fuses in-line with the speaker outputs blown. Fair enough, that was easy enough to replace, they made it quite easy, with the fuseholders being mounted right on the rear panel. The clamps were nowhere near as elastic (or firm) as they might've once been, but with a pair of needle-nose pliers and a bit of creativity, that was no biggie.

Second issue, five of the six lamps that illuminate the tuning scale and the radio signal level were dead. In four of the dead ones, the fillament was attached only at one end, and in the fifth, it was attached at neither end. Interesting little lamps, 6.3v AC, 250mA, in a similar casing as 6x32mm glass fuses. Good luck finding replacement ones (which may very well just end up dying again anyway); these will get replaced with a few white LEDs recovered from a laptop display's backlight.