paul79 Posted April 27, 2016 Share Posted April 27, 2016 (edited) Awhile back a customer contacted me to see if I would take these things on for restoration. After being turned down by a couple other technicians, and the simple fact that he actually has these things, I said I would tackle them. I like the abuse. These are Class A monsters making 100WPC @ 8 ohms. These things running will heat a small house. They were in working condition upon receipt, all the way from Flushing Mi, and I am fixing to dig in. Wish me luck! I might even post some pics along the way. Edited April 27, 2016 by paul79 5 Quote Link to comment Share on other sites More sharing options...
Matthews Posted April 27, 2016 Share Posted April 27, 2016 HOLY SMOKES!!! What I would do to get my hands on them babies... 1 Quote Link to comment Share on other sites More sharing options...
Mike M Posted April 28, 2016 Share Posted April 28, 2016 What do they weigh ? Those look bad *** !!! Quote Link to comment Share on other sites More sharing options...
eth2 Posted April 28, 2016 Share Posted April 28, 2016 Rumor is, they caused the great NYC blackout. 1 Quote Link to comment Share on other sites More sharing options...
paul79 Posted April 28, 2016 Author Share Posted April 28, 2016 About 35 lbs each or so. Quote Link to comment Share on other sites More sharing options...
derrickdj1 Posted April 28, 2016 Share Posted April 28, 2016 Those amps look to be in pretty good shape for something made in the mid 80's. Good luck with the restoration. When finished, those should bring a smile on someone's face. Quote Link to comment Share on other sites More sharing options...
babadono Posted April 28, 2016 Share Posted April 28, 2016 So mainly just recapping or what? What's being restored? I am curious. 1 Quote Link to comment Share on other sites More sharing options...
Schu Posted April 28, 2016 Share Posted April 28, 2016 Very nice Quote Link to comment Share on other sites More sharing options...
paul79 Posted April 28, 2016 Author Share Posted April 28, 2016 (edited) So mainly just recapping or what? What's being restored? I am curious. Mainly yes. All new electrolytic caps including the big main filter caps, relays, bias trimmers, some of the hot running pass transistors, and relay drivers. I also see allot of VD style diodes that will need replaced. They are 34 years old and all original. I have worked on about all the vintage amplifiers, but have never seen these before. Can't wait to plop them in the system for testing Edited April 28, 2016 by paul79 Quote Link to comment Share on other sites More sharing options...
paul79 Posted April 29, 2016 Author Share Posted April 29, 2016 New caps, big cans, and relays. First amp done and running, this is the second. About half done. 2 Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted May 2, 2016 Share Posted May 2, 2016 All passive cooling? Quote Link to comment Share on other sites More sharing options...
Schu Posted May 2, 2016 Share Posted May 2, 2016 Whats the verdict paul? Quote Link to comment Share on other sites More sharing options...
paul79 Posted May 3, 2016 Author Share Posted May 3, 2016 (edited) Yep. All passive cooling, and likely "just enough" heatsink. They designed it pretty well with regards to keeping the caps away from the output section. I haven't seen any heat damage anywhere. Waiting on a couple more relays to finish the second. These take 8 12v relays between the two of them. I am working on a SX-5590 right now while I wait for the parts. Edited May 3, 2016 by paul79 Quote Link to comment Share on other sites More sharing options...
paul79 Posted May 4, 2016 Author Share Posted May 4, 2016 Amps complete, powered up good. Bit more cleanup and final testing. Then they are going in the big rig for eval. Quote Link to comment Share on other sites More sharing options...
muel Posted May 4, 2016 Share Posted May 4, 2016 That is a lot of amp! Getting a little more than 100wpc now? Quote Link to comment Share on other sites More sharing options...
toolz Posted May 4, 2016 Share Posted May 4, 2016 Nice work, on those monsters. Quote Link to comment Share on other sites More sharing options...
paul79 Posted May 4, 2016 Author Share Posted May 4, 2016 Thanks. Spent most of the time re-greasing outputs and pass transistors. 1 Quote Link to comment Share on other sites More sharing options...
paul79 Posted May 4, 2016 Author Share Posted May 4, 2016 They are complex for sure. Allot of trick stages in these things, and allot of FET's. Should sound pretty good. I don't have super high hopes for them though, because there is so much circuitry in them. IME, this usually gets you further from the music in favor of better specs, so the amp will do some things superbly, and other things not so much, but we'll see. Like all amps though, there is a speaker that will work wonders with them. Quote Link to comment Share on other sites More sharing options...
paul79 Posted May 4, 2016 Author Share Posted May 4, 2016 That is a lot of amp! Getting a little more than 100wpc now? Right at 130wpc at rated distortion. Not too shabby! I'll clip them here in a bit.... Still fine tuning the bias. These things run HOT! sitting 8ft away on the computer, and I can feel them. Jeez..... Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted May 4, 2016 Share Posted May 4, 2016 Class A baby. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.