crackling sound from one channel

[ali_azamkhan]

I need help, one of my CJ premier 12 got crackling sound .
When I turn on the amp it work fine but after 10-15 minutes the cracling sound started some time it is low and some time quite noisy.Most of the time when music is playen you can not hear it.
Tubes are fine since I checked all the tubes by replacing with the new set and the problem is still there.

Another Issue in my CJ PV10 , when I turn it on there is a continues hum in both the channels at all volumes.When I hooked it up on one of my ss power amp it tripped.All the circuit is scanned for dry solder and it is fine also the new set of tubes inserted but problem is still there.
Note:Both units are in separate systems
Experts requisted to advise..
regards
Ali

 

[Burnedfingers]

It looks like you have a Conrad Johnson Premier 12. Is this correct? Can you post a schematic of it? This is a tube power amplifier?

It sounds like it may be a bad contact or bad capacitor if I were to make a guess.

The PV10 is a tube preamp?


Maybe this belongs in the tube section instead of the solid state section if the equipment is Conrad Johnson tube product.

 

[Burnedfingers]

I found a schematic for the PV10 but not the Premier 12.

Unfortunately I cannot attach the file because it is too big.

 

[ali_azamkhan]

thanks for the reply, yes both the units are tube and unfortunately i dont have the schematic nor got Conrad Johnson customer support in my country.

I am very new to this forum and it is my first mail thats why my mail landed in the wrong section my appoligies for that.

 

[Richard Ellis]

Suspect PSU....

Is the hum that is present a fifty or sixty hertz tone??????????
If so and at that frequency your PSU cap is suspect....if it is SS rectified and is a push pull (Low idle current) your PSU won't be seeing the cap and will jump up 157 percent of your B+................Or was it if your idle current isn't drawn enough your reverting to pulse charging.........
Or just an old dried up cap.
Tubelab where are you!
____________________________________Rick...........