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
Interesting. How have you connected the CJ 10a to the PF R? Did you go from tape out to a line in?
Need more gain for the Phono stage I think. Sounds like preamp driving the amp too hard (going into A2 operation?).

-Ed
I agree with ED, the phono stage doesn't have enough gain for the Benz Micro.
Not enough gain, agreed.
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!
but it wasn't like this a month ago.
Most definitly, not enough gain. David
I agreed with everybody's comments about insufficient preamp gain for the cartridge, but I don't get the connection with his problems with the power tubes. Has a tube also gone bad?
"09-09-03: Onhwy61
I agreed with everybody's comments about insufficient preamp gain for the cartridge, but I don't get the connection with his problems with the power tubes. Has a tube also gone bad?"
THIS COULD BE IT, YOU STILL NEED MORE GAIN, BUT NOW WITH THE BAD POWER TUBE AND THE LOSS OF POWER, YOU HAVE A MORE PRONOUNCED AND OBOVIOUS PROBLEM. IMHO