Conrad Johnson CAV 50


Just acquired this beauty from my father in law. I've never owned a tube amp, so not sure if I should sell it, or keep it and pay him. Anyway, a question for you tube heads. One of the EL34 tubes in slot V7 ( a tube which can have it's bias adjusted, which I assume means the power transmitted) has it's red light constantly on. I turned the bias all the way down and it still flickers. However, I noticed that my left speaker sounded blown/distorted. When I turned the bias up, the distortion decreased. The instructions say to turn the bias down/counter clockwise, until the red light goes out. But, if I do this, it sounds bad. So, my question is this. Is it simply a tube I need to replace to fix that problem, and if I change one tube, should I change them all. Next question is I searched for the EL34 tubes and of course there are a large variety of them. Any thoughts. To me the amp sounds little bright with the Celstion SL6's I am using, so any warmer tubes would be nice. Also, if I were to sell this setup, any idea on what I might ask on pricing? Thanks.
Roly
rolyasm

Showing 2 responses by tls49

I don't disagree that it's a nice integrated, however the SL6 is the wrong speaker to use with it. The SL6 is a power hungry, inefficient speaker that needs high current SS.
I changed the power tubes (EL34) to the opposite sides and the problem persists.
Did the problem stay on V7 or did it move to the other side? If it stayed on V7, the amp may need to be looked at by a technician. If a tube cannot be biased properly, that should be corrected. Playing it long term will definitely not be good for the tube and if a defective part of the amp is causing the problem, that could affect other parts in the amp as well.

Even if the amp is working properly with new power tubes, it still won't be able to get maximum performance from the SL6.