Alright, so i have a Phoenix gold MS-250 from about 1990. I wired a sub to it that was blown. i was a noob and didnt know what was wrong and i kept trying it. I got a new sub and tried it, it worked for about 5 mins then started smokeing. I know a Capacitor is blown inside for sure, if needed i can take pictures. I can send it off for repair for about $95(110 shipped prolly). I know this is a rare amp, i was wondering if it would be worth it to fix it.
if the amp truly is from 1990 then toss it. you can find an amp that is much more reliable, maybe a little more pricy than the cost for repair, but it would definitely be a smarter investment
"if the amp truly is from 1990 then toss it. you can find an amp that is much more reliable, maybe a little more pricy than the cost for repair, but it would definitely be a smarter investment"
i've seen them sell pretty quick (depending on condition) on forums. if it was mine and i needed it (and could afford it), i would. if it had been the 2 channel up from this, i would be offering to buy it from you right now.
"how many years of use does the amp have. i've never found one that lasts forever. but mike is the genius so listen to him"
who said anything about being a genius (but thanks for the compliment). but to say 'if it's from 1990 then toss it' is really stupid. especially when he's considering sending it in for repairs? really stupid comment. look how many old amps still sell very quickly (depending on the amp), and how many people run older amps, and even prefer them.
Just an FYI that may not be the only bad component. When fixing amplifiers a lot of times when you see one bad component there are others the aren't visibly noticeable.
whey bud, you've got blown diodes and/or transistors in the power supply. I don't know about that pictured cap, but when a cap goes, it either starts to leak electrolytic "goo" or explodes with a bang comparable to a firecracker. I had an ms250 and loved it. very musical but not the best for balls out power if trying to drive a sub with it. It's big deal way back then was it's ability to deliver high current and drive 1 ohm per channel loads (that's a pair of 4 in parallel or a single 2 ohm sub) Did you have the case open when it blew? maybe removed from the heatsink and the reinstalled without ensuring to use isolation pads on the transistor backs to the heatsink? I watched one smoke that way. That smell is likely your output devices that have melted. not to say that your cap isn't bad too. a bulge in the side would indicate that as well. Do you see that white residue that's on the board? That's from a white "smoke" that's emmitted by solid state devices when the junctions between the different internal layers melt down. It looks like both your main "filter/resevior" caps need replacement. also the diodes and trans in the DC to DC buck converter was the initial cause. This part of the amp (where you circled and also the toroid transformer with the red enameled wire wrapped through it is responsible for taking the low voltage from the battery and making about 45 or so volts for the amp to run off of. That takes a bunch of current to do which is why they tell you to use big wires for power. I'd guess you were running it with too low a voltage i.e. 11v or less and pushing it hard. could be a battery on its way out and just over taxing the alternator too hard. Ultimately I'd say if you or a close friend has the skills needed to repair it then go for it and keep it. It's a nice amp. But if you need to spend over 100-125 to repair it then better to put the money into something new. good luck whatever you do. Charles to be honest I'd give you something just for the heatsink...
