Precision Fidelity - C7 Mods...help Wanted!

[brianco]

I have a Precision Fidelity C7 - in basic unmodified form. I want to bring it up to its highest spec. and would be grateful if anyone has a schematic to share for the 7A or REVISED model.

I will be using it with a Bent Audio MC Tx.(Silver) and a variety of power amps.

I will be very pleased to hear from anyone who has worked on this Pre.

Many thanks

Brian

 

[Herrmann]

Hi
Schematic of the C7A-Revised can be found here:
http://www.ys-audio.com
Torben

 

[brianco]

Very many thanks Hermann. That is just what I wanted!

Anyone got experience of these pre-amps? I had the C9 many years ago and wish that I still owned it!! I can't even remember where it went to, but do remember that the power supply was always causing problems when using a voltage drop transformer which gave as little as 110vac. But it DID sound good with an old Moscode!

Brian

 

[brianco]

C7 (Revised)

Herrman kindly gave me a URL for a schematic for the C7 to C7A revision. I would very much like a copy of the C7 (Revised) schematic including it's power supply.

Can anyone help please?

Happy New Year

Brian

 

[patferrari]

Precision Fidelity C-7

The C-7A schematic on ysaudio is not accurate.

What do you need the schematic for?
I have all 3 schematics, and the mods.

 

[Burnedfingers]

I must be blind...I don't see schematics anywhere

 

[brianco]

Thank You...

Pat,

Many thanks indeed: rather than post a full reply I have sent you an email and look forward to your response.

Good luck,

Brian

 

[brianco]

I must be blind...I don't see schematics anywhere

burnedfingers,


Hermann, in post 2, above gave an address which gives the (incorrect) info.

Regarding your (apt?) board name I could be called burned table, carpet, well...virtually everything!

Brian

 

[chevy_lvu]

precision fidelity

hi im a new member and cant email people??? im looking for a schematic for precision fidelity m-8 power amp. also a parts amp?? you can email me at skinnysteve_1@netzero.com I have two amps one works and the other needs help!!!please contact me with any info. steve Ellis

 

[mcelaj]

hi,

patferrari, brianco & others, if any, that has these schematics, i could really use all three schematics. my email is my username at gmail period com.

thanks a bunch.

 

[chevy_lvu]

precision fidelity c-7

hi patferrari I cant email you because I havent made a donation I guess. how much do they what 50.00 is that good enought. also I was wondering about your schematic's on the p.f. preamp. I cant contact you .so please email me at skinnysteve_1@netzero.com I would like to talk to you. thanks steve chevy_lvu on ebay

 

[patferrari]

Precision Fidelity C7 Preamps (All Versions)

To All;
I am so sorry, but I am reluctant to give out the schematics for the 3 variants of the Precision Fidelity C7 preamp.

You see, a while back a guy asked me for the schematics for the Sound Valves VTP-101i preamp and the VTA-70i amp.
Being a nice guy I emailed them to him to help out another tube sound fan who said he wanted to do a few mods.

Now the ******* is out there on eBay selling copies of them!!
I'm sure you all know who I am talking about!

He actually had the nerve to contact me and ask for copies of my Precision Fidelity C7 preamp and M7 amp schematics.

Well, I don't sell schematics because they really aren't mine to sell, and it just isn't right.
I am more than happy to give copies of them to a true person needing help on these out-of-production units.

So there's the dilemma...
Now that I have been ripped off I don't know who I can trust.

I really want to help, but I just don't know how I can.

Sincerely,
-Pat

 

[Cal Weldon]

Pat, no swearing please. I had to manually edit your post. That makes me grumpy.

 

[CrazzyAbtTubes]

Hey patferrari, maybe you should just post the schematics in this thread so that no matter what they would be free, then if someone actually sells them on ebay they won't get away with it because no one will buy them.

The schematic I really need is for the C-8, but I may change it to the C-7 design since the one I have is not in all that great of shape electrically.

 

[DigitalJunkie]

Hey patferrari, maybe you should just post the schematics in this thread so that no matter what they would be free, then if someone actually sells them on ebay they won't get away with it because no one will buy them.

The schematic I really need is for the C-8, but I may change it to the C-7 design since the one I have is not in all that great of shape electrically.

That's kind of my take on it also.Put the schematics out in the public domain,free for everyone to find.
These people selling schematics,and forcing people to take them down so they can sell their copy (*Cough*Heathkit*Cough*) ....Irritates me to no end. 😡

I've started hoarding schematics,and am glad to share any that I have with anyone that needs it. Unfortunately,I don't have the C-7/8 diagrams.

 

[brianco]

Pat has not submitted anything to this site for more than a year so I suggest that you email him as I did I last year. I did not receive a response. But although most members of this site share more than freely, no-one can be forced to share.

 

[CrazzyAbtTubes]

That's kind of my take on it also.Put the schematics out in the public domain,free for everyone to find.
These people selling schematics,and forcing people to take them down so they can sell their copy (*Cough*Heathkit*Cough*) ....Irritates me to no end.

I am glad to have some agreement with this issue, because the way I see it is if I don't get the schematic, I make my own and post them with my projects "It's free use it, modify it, share it, I can't care less, but if you fake it copy it and sell it for some insane price, shame on them!" And will take note of them and spread the word "the schematic is free and of no value to ebay!!! "

That is how I see it, any ways this has nothing to do with the topic even though it is a serious problem and I will see if I can get the schematic from poor old pat who was preveously deceived.


If not... then I shall do my work and draw up a schematic for the C-8 at the very least, and at the rate I am going I will have pages of schematics that no one knows exist, one being the LXI amplifier schematic, which needs an update. 🙄

 

[CrazzyAbtTubes]

Look! The C8 schematic!

Well here it is! I did say I was going to draw it and hey, it wasn't too hard but took a while.

Note, I did not draw the power supply because there is another one that I would use if you plan to build this preamp, and it is basically the same design.

This is the first stage (Phono) so enjoy!

 

[CrazzyAbtTubes]

C7 for C8?

I always search for a schematic of this preamp but can only find the one on that site that everyone disagrees with.... I don't understand it looks like it would work just fine, the concept is strange but will it work right if I built it from scratch?

It is rather frustrating that everyone complains and brags about this preamp yet no one tries to make a revised rebuild.

I completely rebuilt the C8 from scratch, I think I used the power supply from the C4 .... worked just as well and I slapped the regulators down to a massive heat sink solving the heat failure problem but changed the sound in my opinion.

I will make a bargan with someone, if they are willing to send me the true revised version of the C7 (does not need to include the power supply as I can make my own), I will send them all of the C8 schematics along with pictures and parts info.

I am building an all out preamp and want to use the best RIAA stage I can find and the C7 stands out from all others.

 

[geordidog]

I know this is impossible but perhaps someone has schematics for the Precision Fidelity C-9?
Any help would be greatly appreciated since I have one that has been modified and would like to bring it back to original condition.
Thanks, Bob
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