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Precision Fidelity C-7A Revised

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I have a Precision Fidelity C-7A Revised I was considering putting up for auction on the big E and while surfing for estimated value stumbled onto this site. In a thread regarding this Pre-amp the value was suggested at approximately $300. That person was politely chastised for that estimate and noted that it is worth at least twice that. My thinking is that it's worth whatever someone is willing to pay in regards to supply and demand. Any help would be appreciated. Or if anyone on this site is interested please contact me.

The pre-amp is in top condition, no physical damage or marks that I can see. I will be testing the functionality in a couple of days. It should work fine as it did the the last time I listened to it. I have the original manual and warranty card but I do not have the original box.

There had also been requests on this site for the schematics. The manual does include the schematics and I will gladly scan and email to anyone needing.

I also have a Walker CJ55 turntable with a Linn Basik arm that may go onto the block as well. Any interest?

Thanks in advance,
Jeff
 
Precision Fidelity C7 schematic

Hi Jeff,
I bought a C7 in mostly stock condition and would like to bring it up to A-Revised level. If you could dig up the schematics I would be grateful.
I have replaced the RCA's in mine and the two volume pots with Goldpoint and it makes for a huge improvement.
It just occurred to me that my old email business address is on the DIY server and I just retired. I will try to change that right now but my new address is Becfin55@gmail.com.
Thank you
Lloyd
 
I sold one to a guy in Spain/Portugal a couple of years ago. I too had contemplated updating it to the final spec., but was warned by a few people both here and elsewhere that the easily found (on the web) circuit for these updates has errors. If wanting one I would now build from scratch (point to point) as the components are easy to source and many of the original components can be improved.

I also had a C4 (the big multi facility version) which I used as a go to pre amp. It was an American domestic version and I had to run it through a 120-240 transformer. The power supply frequently needed rebuilding. So I think that you would do better to do a total rebuild (scrapping the PCB and every original component) using a good proven PS in place of the original. I suspect that one of the Aikido PS versions would fit in the chassis and also be a vast improvement on the original. Also replace the original switches and attenuator with new decent quality versions.

I have searched my Mac for the schematics and some 4 TB of disc space, but seem to have thrown them out when I bought a newMac. The attached pic is all I could find! (This was a European model sourced from Germany…probably originally bought in a PX store!!)
 

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Hey there gentleman. I just picked up a dusty, old C7 off the big E myself. CrazzyAbtTubes, do you have the power supply schematic? On mine, someone modded the power supply by removing voltage regulators(?), capacitors, and resistors. In place they installed some big resistors and put a cap across two legs of the existing regulator. The seller bought it like this over 20 years ago so he's not sure what or why this was done.

A lot of parts in this thing need to be updated, so a schematic would be nice, but I'd settle for some high res photos and/or a part list of what used to be there. Pretty much anything would be really helpful. And anyone got any idea why this mod was made?
 

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