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Old 3rd December 2008, 10:43 PM   #11
wingzam is offline wingzam  United States
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Rob,my account is STILL under moderation so instead of e-mailing you directly I have to reply thru this post.My e-mail address is (address removed by mod) added a Rotel rdc-950 cd player,Pioneer burner to the system as well as upgading the cables and wires.Picked up Jimi Hendrix Crash Landing and Midnight Lightning...now am chomping at the bit to work on the amp so you're right on time!How did things go with your amp?
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Old 3rd December 2008, 10:44 PM   #12
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wingzam you are now free of moderation. Go forth and multiply young man. I have removed your email address to keep it from prying eyes.
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Old 3rd December 2008, 11:12 PM   #13
wingzam is offline wingzam  United States
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Cal you are an ape among chimps!A Man among apes!!A king among men!!!A god among kings...I SHALL go forth and multiply - but where is this Eve girl you've been telling me about??
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Old 4th December 2008, 12:19 AM   #14
rob3262 is offline rob3262  United States
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Wingzam, you've got mail.

My A5002 is on hold while I venture into Leach amps (Jens Rasmussen clone)

Last effort was to diagnose a buzz that permeates throughout the amp, including signal and chassis grounds Being from the 80's, I'm sure that the large electrolytics need to be replaced. So... if you find appropriate size/rated PS Caps, let me know.

I don't have a PCB layout either
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Old 4th December 2008, 12:27 AM   #15
rob3262 is offline rob3262  United States
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Quote:
Originally posted by wingzam
Rob,my account is STILL under moderation so instead of e-mailing you directly I have to reply thru this post.My e-mail address is (address removed by mod) added a Rotel rdc-950 cd player,Pioneer burner to the system as well as upgading the cables and wires.Picked up Jimi Hendrix Crash Landing and Midnight Lightning...now am chomping at the bit to work on the amp so you're right on time!How did things go with your amp?
I have a Rotel RCD-971 player running into a QSC RMX2450 on the bedroom system. With upgraded wires.
Sure wish I had Crash Landing to play thru it...
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Old 4th December 2008, 03:01 AM   #16
wingzam is offline wingzam  United States
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Ya,if I had more $$ I would venture off to a different amp myself.This electronics learning curve is a real bitch..not to mention gathering all the info to get the job done.Still,Polk Audio forums aside,Soundcraftsmen amps appear to be fairly highly regarded so i'd like to see what I can get out of it on my own.
I got this info from Goat67 at Audio karma whose advice appears to be highly regarded.On the big main power caps - Mouser P/N's:
Original part at schematic location C32 & C35=
30v 22,000uf.Upgrade to 40v 40,000uf P/N 75-36DY403F040BC2A.
Original part at schematic location C33 & C34=60v 11,000uf.Upgrade to 75v 18,000uf P/N 75-36DY183F075BC2A.

Here on diyAudio some time ago a member said he had replaced the 11,000uf caps with Aerovox M series 41,000uf caps and the 22,000uf caps with Aerovox M series 39,000uf caps.You'll notice that the 11's got bigger caps than the 22's(did'nt list voltages).Don't know if this was a mistake in his post.
There are two companies that have schematics for our amps:vintageaudiomanuals.com & musicparts.com.It's a little confusing figuring out which one to order from.Music parts(go to their site) seems to have a more complete package of info which is sent as a PDF file with a page size of 8x11,whereas Vintage audio sends out high quality 11x17 schematics and says "our schematics include a wealth of service info,includes troubleshooting tips,modifications,parts substitution,amplifier testing and voltage conversion procedures."...
So I don't know which set to buy.They're both $20.
Additionally Vintage audio schematics cover all the class H amps (probably including yours)whereas Music parts is specific to the model.
I got your e-mail attachment,but have to crash now so will download it tomorrow.Hopefully we can piece this together and get these things rockin!
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Old 4th December 2008, 03:06 AM   #17
wingzam is offline wingzam  United States
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Crash Landing has what I think is the greatest lick ever recorded...and Midnight Lightning..his blues playing is just...wow....
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Old 4th December 2008, 10:14 PM   #18
rob3262 is offline rob3262  United States
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Quote:
Originally posted by wingzam
I got this info from Goat67 at Audio karma whose advice appears to be highly regarded.On the big main power caps - Mouser P/N's:
Original part at schematic location C32 & C35=
30v 22,000uf.Upgrade to 40v 40,000uf P/N 75-36DY403F040BC2A.
Original part at schematic location C33 & C34=60v 11,000uf.Upgrade to 75v 18,000uf P/N 75-36DY183F075BC2A.
The MA5002 has 62v & 93v rails, I'm sure the Mouser #'s won't work for me.

Quote:
Here on diyAudio some time ago a member said he had replaced the 11,000uf caps with Aerovox M series 41,000uf caps and the 22,000uf caps with Aerovox M series 39,000uf caps.You'll notice that the 11's got bigger caps than the 22's(did'nt list voltages).Don't know if this was a mistake in his post.
If bigger caps will fit either position, I would shoehorn them in! I'll expect to pay over $100 for new electrolytics from what I've seen.
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