Need some advice PLEASE!!!!

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 4:35 am

Hi everyone,

First off Im kinda new at this collecting really old (88-95) audio equipment. But anyways Ive been installing and what ever else for about 13 yrs now. I wouldnt say Im great at it but ud be amazed at what I can do with "nothing". But anyways I jus got me so really old PG stuff about a yr ago MS275, MQ430 (both gray) and a TBA-1 reciever (no transmitter). I everything else I have is on my signature. But I never realized how good say the first 3-4 gen PG stuff was compared to every other brand untill I opened them up and looked at them. Now my standards are no less than the MS, MQ, and MPS lines. Well except the first gen soundstream ref series. But anyways my aunt used to work for Hammond Nose Stereo's up in columbus, OH way back (85-95) they were one of the best shops in the country back then. I have pics of her old car with about 50 speakers ran off of an old rockford punch 50 hiting around 120 db back in 89'. But thats what got me into the really old stuff cause nowadays no one is makeing stuff like that anymore. But all my old PG stuff works great and sounds amazing. I wanna get my soundstream working again to use it to push my sub, instead of the kicker I have. but it doesnt seem to power up at all. I have the board out of it now and theres no marks on the board of anything bad on it and it doesnt smell at all either if any1 has any advice please reply to this post. Also my old PG stuff hasnt had any work done to them should I replace or send it somewhere to be up graded to they wont kick the bucket on me. Also if any1 has a MS2125 (has to be gray & original inside) they would like to sell let me know Id be very intereseted. Well guys I have allot more I could say but I know yall are get bored with this but if any1 has any advice please let me know Im always on here when Im not at work. I appreciate any feedback thanx in advance

Post by **Eric D** » Mon May 04, 2009 5:37 am

You really should consider having the capacitors replaced in your MS amplifiers. Amps of that age have capacitor problems and could end up looking like the photos you see below. Also, the Soundstream amp may be a simple fix, but you need to post some photos of the board so we can give you some direction…

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 6:19 am

I took pics for ya and I used my cellphone sorry only cam I got. But I hope they are sufficient enough. Now the only "distress" I see is one of 3 little brown resistors (the single by itself) next to 2 little caps is brown in the middle and one of those 2 caps isnt bright yellow like the others its a little brownish tint to it. Now the rest of the board looks good. Also on my MS amps can I upgrade the caps to better ones to help them put out better SQ or jus replace with same type and if you or anyone else have any other advice I would really appreciate in advance thanx.

Post by **Eric D** » Mon May 04, 2009 7:17 am

You should start by checking the transistors I have circled in the photo below. Use a DMM in diode check to mode to look for shorts and post what you find.

Also, I am sure you know this, but your amp needs a fuse in order to work. I did not see it in the photo, so I figured I better mention it anyway.

When I replace the caps on MS amps I put the largest I can physically fit in them. This gives the amp greater reserves when it needs it and the power cable can not keep up.

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 7:49 am

this sounds stupid maybe but there in no fuse holder on the board so the only way is to put one on the power cable in-line like in a car if so the amp can detect this. so i tested those 4 transistors. they all read the same positive kept on same 1st prong the whole time the negative moved to 3rd leg on all 4 read .75 but when checked on all 4 middle prong the read continued to increase up to .45 and would stop there

marko · Post by **marko** » Mon May 04, 2009 7:58 am

the fuse holder is them 2 spade connectors, even without a fuse the fault led will light up when powered up...

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 8:02 am

oh crap hold on guys let me put one in and ill let u know what happens

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 8:51 am

I knew there was a reason it sat apart in my garage I got a while back and it never powered on even w the fuse in it. I just put it on my "test" bench an applied power to it and ..... NOTHING .... not fault light , no blowing fuses nothing except the little spark from the ground terminal when hooked up but thats it guys anything else please Im desperate to get this thing working again thanx in advance

marko · Post by **marko** » Mon May 04, 2009 8:57 am

they are a sweet sounding amp, i got 3 of them and use them for testing stuff and they have all been repaired when i 1st got them, mostly needed outputs so check them but usually you would get a fault light come up on them.

my gut feeling is something in the power supply or remote turn on section if it doen't power up at all...

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 9:34 am

how whould I check the remote turn on section

marko · Post by **marko** » Mon May 04, 2009 9:53 am

knightrider358 wrote:how whould I check the remote turn on section

trace it back from the remote terminal to the pwm, there's loads that could be wrong and this was just one suggestion..

knightrider358 · Post by **knightrider358** » Mon May 04, 2009 11:00 am

after I trace it how would I check it to be good or bad? Im really open to ideas or whatever to try to determine the prob and maybe fix it please anything