#81 MOTU Traveler teardown & upgrade

As a follow-up to the recently posted MOTU Ultralite teardown, i had to grab this as soon as it popped up in my search results, because it had a price i couldn't ignore or refuse, and it had the ideal feature set for recording my band's jams and rehearsals. While the former had most of the features i needed in the 828mk2 i had been using, but in a smaller form factor, this Traveler packs more of the features i need (two extra mic preamps, while retaining the -10dBV/+4dBu line inputs with optional 6dB boost), in an intermediate form factor, as well as having a full 53dB of gain available on the mic preamps, but without weirdo custom potentiometers to wear out. Just about best of all worlds, really, especially for the paltry 85e this cost me. And as the cherry on top, it even has a separate battery input - hello, fully mobile recording sessions...

 

 

#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).

#61 MOTU 896 mk3 Hybrid teardown (post-recap)

Since relatively recently acquiring the MOTU 8M, once i got around to swapping it out for the 896 mk3 in my recording rack, i figured it might be worth doing a quick teardown of the latter, before i sell it off. I've done a really brief one over on the BadCaps.net forums when i first bought it, but it deserves some higher-res photos and a more detailed documentation of its guts. Do keep in mind that it got re-capped as soon as i got my hands on (or into?) it, so the electrolytics are not stock. But
without further ado...

#56 Apogee Ensemble Firewire teardown

[[[ Repair can be found here ]]]

This came up on eBay the other week as faulty - inputs 1/2 and outputs 1/2 seemingly dead. First instinct was, 'obviously', look up photos online in the hope of finding some internal shots. A few minutes later, bingo: four CS4272's in there. Now, what're the odds one of them is handling the bad pair of ins & outs? Quite a bit higher than the analog input of one, and the analog output of another to be bad, wouldn't you say? But let's not get ahead of ourselves (too much), and take things one step at a time...

#54 Recycled backlight LED strip ambient lighting

What with winter drawing closer, and the days (as in daylight) getting shorter up here in the north, one tends to need to turn on the lights more and earlier than in summertime. And since i'm the gathering type, i figured it's about time i put some previously collected materials to (good?) use.

#25 Behringer ADA8000 "Ultragain Digital" revival

I got my hands on one of these Behringer Ultragain Pro-8 Digital a few months ago, as faulty (as in, totally dead) for about 50$ shipped. Having done some preemptive googling before going for it, i was expecting the transformer to be toasted. Sure enough, that's exactly what the problem was - one half of the center-tapped primary measured in the hundreds of kohm, so pretty much open-circuit (as opposed to the 50-odd ohms the remaining good half measured).

Initially i was planning on finding / getting a "drop-in replacement" toroidal transformer, ie. similarly sized physically and power-wise, but with less insanely-high secondary voltages. The stock one, according to some "inspection notes" i found online, seems to have had roughly 2x20VAC windings for the analog +/-15V (meaning the voltage regulators had to "burn off" uselessly much power / voltage), 12VAC for the 5V regulators, and a whopping 58VAC winding for the phantom power regulator. That's about a 50% overkill across the board. One can only wonder just what possessed them to spec the transformer quite like that, especially since it must've been a custom order - you'll rarely find retail units with more than two (identical) secondary windings, and when you do, expect to pay a pretty penny for'em.

#21 SM Pro Audio TB202 dual tube preamp / channel strip modding & upgrade

<Further developments can be found in parts two, three and four>

I'll admit, this was a bit of a lucky catch, in that it was mistakenly listed in the wrong eBay category, but one i "stalk" for good deals on certain faulty bits of audio gear. It was up for auction, there didn't seem to be much demand for it, and i ended up winning it for a mere 21 euros. About as much as the shipping for it ended up costing, oddly enough.

But still, even for some 40-odd bucks, not a bad little unit. Two channels, a (bare-bones-ish) compressor on each (1.5-10:1 ratio, 1ms/5ms attack, 500ms/1500ms release, at least according to the specs in the manual), as well as 3-band EQ (80Hz shelving / 1.8kHz bell / 8kHz shelving), and there's a tube / valve involved in the circuitry as well. If nothing else, i figured it would do nicely as a bass DI (or even an overdriven preamp, once some internal re-wiring is figured out and done).

#20 SM Pro Audio TB202 power supply repair

<Some sort of continuation from another post>

Buuuuut that brings us to what might as well amount up to the proverbial "elephant in the room" - the power supply. No markings or label anywhere on it - if i didn't know any better, i could almost say it never had any (no adhesive residues or anything). Fortunately, it was held together with four Phillips-head self-tapping screws, so "disrobing" it wasn't unecessarily traumatic. That being said, what greeted my eyes, sort of WAS.

#16 Cheap chinese BM700 / BM800 microphone modding / upgrade, part 2 (CK12 & K47 capsules)

<Continuation from part 1>

After quite a while, i "finally" got around to modding the other three BM800 mics i had. Just for the hell of it, i decided to make a matched triplet (to use as, say, three overheads on a big drum set).

I went with more of my modded-Schoeps boards, and matched components between them, as closely as i could (within reason, at least). Resistors were no big deal, and neither were the capacitors; one of those cheapo chinese ATMega328-based "component testers" helped with matching the JFETs and PNP transistors. No, i didn't necessarily care about the absolute values, just that they're the same (or as close as reasonably possible).

#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.

#12 Cheap chinese BM700 / BM800 microphone modding / upgrade (to say the least).

<Part 2 can be found right over here>

Last year, after hearing (or rather, after reading) about these cheapo BM700 / BM800 microphones, over on the GroupDIY forum, i decided to get a few myself. They were cheap enough (under 20 bucks a piece), and i figured they would, at the very least, make for reasonable enough donor bodies.

Some credit is due in no small part to Mr. Henry Spragens, whose microphone section on his blog served as a considerable portion of inspiration for this endeavour. Said blog is a fountain of knowledge, testing and ideas for anyone interested in condenser microphone modding or even building from scratch.

#11 sE Electronics sE X1 rebuild

It's been a good few years since this mic (sE Electronics X1) came into my possession. As many others i have, i bought this one as faulty. The main problem was, it was noisy as hell (think wind-noise, or the sound of blowing straight into a microphone).

Once i had another capsule to test this with (a temporarily removed capsule from a Shure KSM27), i figured i'd hook it up to the X1 to see whether the capsule was the source of the noise. Nope, the noise was still there. After i ruled out the (stock) capsule, i replaced it with a 100pF styroflex capacitor, for minimal hassle (and risk of damaging a capsule) during subsequent testing of the electronics.

#9 Revisited: Amphion Impact 500 (DB Series DB5004) subwoofer amplifier - DONE!

Got the fresh parts the other week, and installed them all. That, plus rebuilding the two blown and "distressed" traces, respectively.

#3 MOTU 8Pre teardown & gain adjustment pot replacement

On the latest drum tracking session i surprisingly discovered that channel 8 on the MOTU 8pre in my recording rig was noisy and useful-signal-less. This same unit had a similar issue with channel 6 when i bought it (as faulty, with a shot Firewire chip).

Fortunately, when i was about to take care of ch6, i got two replacement pots. When investigating the issue, i had read it's a relatively common occurrence, so i figured that as long as i'm contacting the local MOTU distributor, might as well get an extra / spare one, just in case (especially since i had two 8Pres at the time).