Saturday, December 27, 2008

Pioneer SPEC 4 Amp Repair

I first saw and heard a SPEC system set up back in 1980 when I was stationed in Guam while in the Air Force. I never forgot it and 20 something years later, I finally got a chance to get my hands on a SPEC 1 pre-amp and a SPEC 4 power amp in very good condition. I had already had the other pieces of my system and was using a nice Pioneer SA-9500 II to power the restored Bose 901 Series IV's, which took me the better part of a month to bring them back from the dead. When I hooked up the SPEC 1 and 4, there was no comparsion. The depth and clarity of the music that the SPEC components produced went way beyond what the 9500 II could muster. I was in heaven...... for a while. About six months later, I got up one morning and went to turn on some tunes like I did every morning and flipped the power amp switch on and nothing. No lights, no nothing. I knew I was in trouble. I live in North Alabama and there was no repair shop anywhere around here that was capable of this kind of work, but I took a chance and carried it to a local electronic shop anyway, mostly out of desperation. Here, let me give a word of advice to anyone who needs a vintage stereo component repaired: if the place you take it to has alot of TV's sitting out, turn around and walk back out the door you came in. That guy kept it a month and was no closer to repairing it than the day I brought it in. Finally, I'd had enough and starting looking around on the net for a real repair shop to ship it to. I looked a several ads and read their sales pitch and then I saw and read the reviews for Austin Stereo Repair in Austin, Texas and knew this was the place I wanted to work on my SPEC 4. Mike, the guy who runs the shop, was very nice and kept me informed of everything and every step of the repair process that he was making. The turn around time was a bit longer but that was entirely my fault. He told me exactly how to pack the amp to ship to him and like a idiot, I didn't listen to him and tried to save a few bucks by not wrapping it in bubble wrap. The amp arrived with a busted bumper on the back. It could have been alot worse and I learned my lesson. If you ship to him and he tells you how to pack it, take my advice; do it! Finally, I got it back and let me tell you, I cannot write a good enough review for the work Mike performed. It sounds better than it did before it died! Also, this guy must be a clean freak because you can eat off the inside of this amp! Austin Stereo has my business from now on. Thanks Mike!

3 comments:

Anonymous said...

Howdy - Was looking at your repair on the Pioneer Spec 4 and was wondering what the problem was and how it was resolved.

Thanks - Gip

Nat said...

This article was written by a customer of Austin Stereo Service and not one of our usual bloggers. The gentleman asked for the opportunity and we were happy to accommodate his request.

I was witness to portions of the work. Problem #1 was the shipping. People just do not realize how much damage heavy electronics can sustain when not adequately packed. Read the article on this blog about using swim noodles: they really work! And scrimping on the box is an exercise in false economy.

Electronically, this was a restoration, not really a repair. These units are all nearing the end of their first life. The caps are aging, and they not only do not sound their best, but they are increasingly at risk of catastrophic failure.

Without a doubt every single capacitor in this unit was replaced with the possible exception of the main filters. It is likely that some active components were replaced, either due to failure or signs of stress. When these amps fail things get hot.

Mike has noticed that the main filters are increasingly a source of major failure, especially when these amps are run with out of spec power supplies. When those little caps fail the voltages can get ugly. I have worked on a Pioneer SX-1250 with a hacked up regulator card that caused two of the main filters to vent into the bottom of the case. It's foolish to let that happen.

I will try to track down the details of the work and provide a more detailed accounting later this week.

Anonymous said...

This is stang98 and posted the comment about the Pioneer SPEC 4 Amp Repair back in 2008. I still have that SPEC 4 along with the SPEC 1 and the SPEC 4 is still singing beautifully! Thanks Mike!