2. analog
  3. 1063038973

something is wrong here, but what is it?

Here is my set up: CJ PF-R Pre, CJ MV-55 tube amp and a CJ PV-10A used for a standalone phono pre. When I play any source other than phono, the sound is just fine and the amp works nicely, when I switch to phono, the sound is low (I have a low output cart. Benz Micro Ref.)and as soon as I bring the volume to a decent listening level, my bias lights start going crazy, the blue gaseous lights in the EL34s start flickering and the distortion is very painful.
The Amp and the PV-10 tubes are fairly new. What am I missing? all comments are greatly appreciated.
thanks
Shahen
shahens
ed_sawyer
588 posts
 
Need more gain for the Phono stage I think. Sounds like preamp driving the amp too hard (going into A2 operation?).

-Ed
paulg805
29 posts
 
I agree with ED, the phono stage doesn't have enough gain for the Benz Micro.
twl
3,251 posts
 
Not enough gain, agreed.
shahens OP
27 posts
 
but it wasn't like this a month ago.
dougdeacon
3,338 posts
 
Shahens,

Hi from another c-j-ophile!

I have a PV11 preamp with phono stage. When I ran my new low output MC cartridge directly into it, the sound was flat, lifeless and too low in volume. Turning the volume up made tube noise from the preamp very audible. If I had a nice tube power amp like yours I'd also expect the problems you describe. Insufficient gain is definitely your problem, the c-j phono stages are made for high output MM cartridges.

You must either change phono stages, add a stepup transformer or go back to a high output cartridge that won't perform as well.

I went the stepup transformer route. The ones from BentAudio sound great and John Chapman is very helpful with us newbies. Obviously there are others out there, many perhaps for fewer $.

Good luck!
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