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  3. 161953-9815

Madrigal Proceed PAV Schematics

I have a Proceed PAV (the one with button volume control instead of knob) that I inherited from my uncle. I was using it just for 2 channel listening. It started shutting itself off intermittently when I adjusted the volume level. Now, when I power it on, all of the lights go on for a second, and then blank and then I hear a regular clicking sound. I assume that's a relay. Any advice on this issue would be appreciated.
But I am also looking to obtain the schematics or service manual for this component. Madrigal Labs is out of business, and I can't find any contact info for Madrigal/Mark Levinson on the Harman International website.
ubersujith
ubersujith OP
9 posts
 
Wow! Thanks so much, auxinput. I'll let you know how we get on. I'll have to price out recapping the entire board and then make a decision, but I would love to. This is by far, the best sounding pre-amp I own. By which I mean transparent. I didn't even understand what that meant until I plugged this into my system.
auxinput
2,920 posts
 
Are you planning on doing the re-cap yourself?  Or having somebody do it?
ubersujith OP
9 posts
 
A local shop is doing the work. Not retail, just a repair shop fixing hi-fi and musical instruments, who are attached to a practice studio. They have done good work for me in the past, and I trust them.
auxinput
2,920 posts
 
You may not have any control over what choice of capacitors they use in the PAV.  I know some of these older equipment used specific brands/models of capacitors to get a certain sonic signature.  If they are just a hi-fi / music repair shop, they may use the cheapest capacitors available for a generic "fixit" solution.  It may change the voice of the PAV.

For what it's worth, I have found the Nichicon KZ caps to be the absolute best for a smaller size cap (1000uf or under).  These are absolutely excellent, but they are larger in physical size and will often not fit into a specific location.  It's often worth it to try to shoe-horn in these caps even if they are sticking out with 1/2" of lead.

For places where the KZ caps can't fit, the Nichicon KW caps are the next best thing.  You will probably have to use KW for the big main power supply caps anyways.

If your repair guy can identify the "standby power supply section", then I would advise using something like the Nichicon PW caps, or something that has a long life (such as 5000 hours at 105 degree).  These definitely don't need the KW/KZ audio caps.
ubersujith OP
9 posts
 
Wow, thanks again. I will pass this info along. Unfortunately, without the schematics and electrical signal paths and values, the tech says it would be expensive were he to engage in trial and error, and he couldn't guarantee success. I'm going to spend a few days tracking down leads, before I give up.
Sure, I could send it off to a fancy shop in Colorado or Seattle, but it's much more fun to do it hard (and cheaper) way.
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