Lower gain in left channel.


I just noticed last night that the volume from my left speaker is lower than my right speaker. It is enough that images are pulled towards the right speaker, but it is not glaring. Could this be a sympton of a power tube going bad? I'm running An Air Tight Preamp (with 6 month old new tubes) and a c-j Premiere 11A. I'm not sure the age of any of the tubes of the c-j, I bought it used and have had it for about 1 1/2 years. Would a tube or tubes going bad manifest in this way. There are no strange noises or anything coming from the left channel, just the slightly lowered gain. Thanks for your help.
128x128jond
Jond; I've had the problem you describe for years, and it's why I always use a pre-amp with channel balance control. My left channel output volume is higher than the right channel, so I always have to dial in about 3-5 dB (biased to the right) of volume to achieve good channel balance and proper imaging. I CAN get good imaging by slightly biasing my listening position-- which is then slightly off center.

I've blamed my room, my speaker set-up, my hearing etc, but in 4-5 years in my present room have yet to figure out why this is the case. I've also changed tubes in my pre-amp several times and it has made no difference. Sorry I can't help. I'll follow this thread with interest. Craig
I'm experiencing the same problem. I was getting a constant hum from the right channel of my OTL amp. I took it in for repair. Apparently one of the capacitors (there are 2 per channel on my amp) on the right side had gone bad and needed replacement. After replacing the capacitor the hum went away but, I started to notice this ever so slight loss of gain from the right. I tried the tube switching but without success. What could be causing this? Hope someone can shed some light on this. I know it's not my preamp because I was able to try a different amp last night -- there were no loss on right channel.
I would suggest narrowing the problem to a particular piece of hardware. Maybe you've already done so, but I would swap the cables between preamp and power amp, and swap speaker cables or speakers whichever is easiest. I had a similar problem with a pair of electostatics and it turned out to be the crossover in one speaker was bad. Oddly enough it was the speaker that was loudest that was the culprit.
Jim Robinson

Some music is recorded that way, you'll notice a difference on some recordings from song to song...