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PostPosted: 23 Jul 2009, 17:21 
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Joined: 14 Oct 2008, 17:35
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Location: Dartmouth, Nova Scotia
Now that I have drawn this schematic it is time to post it for people who are needing it, and its free!! So respect it because I cannot find it any wheres.
Attachment:
Precision Fidelity C-8 Preamp(small).jpg
Attachment:
Precision Fidelity C-8 Second Stage.jpg

So you are probably wondering how I got it.... well its not that hard to follow PCB traces is it?


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PostPosted: 23 Jul 2009, 21:43 
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Joined: 28 May 2008, 21:53
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Location: Winnipeg, CANADA
Alan, Thanks for making and sharing the Precision Fidelity C-8 Preamplifier Schematic.

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PostPosted: 25 Jul 2009, 07:18 
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Your welcome Gio, there are allot of people searching for this schematic and I just happen to have the preamp, a very strange design indeed, especially the Phono stage, very complex.

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PostPosted: 09 Jul 2010, 11:04 
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Do you have a Precision Fidelity M8 one? I saw one for sale and it only had 2 tubes in it. Mine, 4 - 12ax7 and 4 caps in filter supply while this one had only 2. Go figure.
Thanks


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PostPosted: 15 Jul 2010, 15:02 
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I have never heard of the M8 before? Are you sure yours is not mistaken as being the C8? Take a picture if you can, I would like to see the one you have. If you are interested in doing upgrades or repairs to the one you have just let me know, I have all of the schematics for the C8 and lots of optional mods. :P

Here, this thread I made has allot more information.....

viewtopic.php?f=9&t=970&start=0

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PostPosted: 09 Apr 2011, 22:06 
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Joined: 24 Jan 2011, 15:52
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Hey Alan, do you have these schematics in a higher resolution? Page 1 is unreadable. I realize it's been a couple of years, but I thought you might still be around.

Thanks for posting.
Adam
CrazzyAbtTubes wrote:
Attachment:
Precision Fidelity C-8 Preamp(small).jpg
Attachment:
Precision Fidelity C-8 Second Stage.jpg


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PostPosted: 11 Apr 2011, 01:25 
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Got it to work when opened as a new window. I think I downloaded the jpg preview before.

Adam


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PostPosted: 11 Apr 2011, 07:07 
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Thank you! :D

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PostPosted: 11 Apr 2011, 15:25 
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The power supply is around here some wheres too.....

Here it is: viewtopic.php?f=9&t=991

Sadly, I no longer have the phono stage schematic on my computer, I don't have express PCB draw file either, some how they got deleted or lost when I had to move everything off my old computer so I had to pull the image off the forum here, thank goodness for that. :)

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PostPosted: 13 Apr 2011, 22:51 
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Joined: 04 Jun 2008, 20:59
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Location: Arizona, USA
Hi, Thanks for posting the schemo. I like to see how others have done the phono stage. A peculiar design, but I'm sure it will work. 8-) I put my own project on the back burner for a while as I'm getting ready to go to the Dallas LASF next month and only want to bring perfected stuff. My tube phono preamp was rather good, but not up to what I wanted. The C8 uses passive equalization. Mine is active. I tried both and there are advantages to either type. I felt the active had lower distortion and was less prone to picking up hum and noise. The downside seemed to be that it needed a buffered output stage or else the following stage could load the network and throw off the equalization. :(

Good listening
Bruce

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