And here we are, on the third and final(?) part of the modding journey involving this little fella. As presented in the previous post, i managed to "persuade" the thing to power up fully despite not being attached to a computer, only to a USB-connected 5V source. But now, the time has come to integrate what is virtually a "power-bank", within the enclosure, and thus have the Saffire be entirely "self-sufficient", as it were.
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.
And now, getting back to the issue affecting this unit... As pointed out in the ad, the LT3439 apparently used to have a piddly little heatsink glued on top of it, but it got detached. Now, there's a chicken-and-egg type mystery here - did the heatsink glue fail because the chip overheated in the first place? Or did the chip get fried because the heatsink fell off? Regardless, investigation showed that one of the two switching transistors inside the chip seems to be stuck in a conducting state, despite the transistor itself not being shorted, though. But since it handles all the power for the analog circuitry, it's no shocker (no pun intended) that only the digital ins & outs work.
