Recapping Cambridge Audio 640P Phono Preamp

Hmm go figure. I pulled the op amps and it seem that maybe one was toast. I replaced the offending op amp that was in the output stage with one of the original ones and I get 18v and the relay kicks on.
 
Works! I put the NE5532s back in the output for now. Ordering a new set of LM4562's and some OPA2134's to try out. I'm currently using the AD823 in the input. Now I have to wait till tomorrow for critical listening when my wife isn't spleeping! :)

I want to extend my sincerest gratitude to all of everybody's help! I'm a weekend warrior and I learn something new with every project. I think, aside from op amp rolling, I'm calling this one done before I make real mess of the board ;)
 
I'm getting an intermittent scruffily noise noise out of one channel. What could that be? Week solder point perhaps? It reminds me of my old mini millet max that would do that sometimes and I'd tap on it till it went away.
 
Went through and double checked the joints remelting the solder in a bunch of spots and reseated the op-amps. I think that did it. No issues and sounds very good. Colexico is almost inthe room with me.
 
Glad you worked it out, just make sure the op amps aren't overheating and you should be in the clear.
 
I powered it up and let us sit for a moment while checking the heat and no issues. Has been running for a day now. Without fault. Avoiding temptations to keep going. New op amps should be in tomarrow. I also ordered some opa2132s to try out. New power regulators came in today. I bought them just in case those were the issue. The ones I got are supposed to have better ripple regection. Do you think this would be a worthwhile swap?

Getting a bit more noise than I remember. Perhaps it's the cheap resistors I put in place to make up the 91ohms. 91ohm PRP resistors should be here soon. Currently using a metal film and a carbon film in parellel to get 91ohm since that's all I had on hand. Could a ground resistor in that location really have any effect on noise?
 
When I said I was done tinkering, I lied.

I've replaced the odd resistor combo for 91r with a pair of Shinko 68r tantalum a and put in the Ad823 and let that settle in for a bit. This gave me a slight increase in volume and a cleaner signal overall. I the AD823 give it a slightly more laid back sound which I think I like. After a few weeks of getting to know that setup, I've just installed some audio note 47k non magnetic tantalum resistors on the outputs. WOW! I'm a believer! These opened up the sound to no small degree. The noise floor is better and the decay of instruments is like nothing I've heard. I've, so far only listened to Verve records pressing of Oscar Peterson's "we get requests" the triangle rings like I've never heard before, where before you could tell there was a triangle, now I hear the decay of it go on for ages. Timber and musicality, everything really, just improves across the spectrum. This really surprised me. Next is to swap in the other op-amps. Has anyone tried Berson Audio's V5i Hybrid op-amps?
 
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