Large Channel Imbalence KEL84

[mudvin]

Hi All,

My newly completed KEL 84 has an issue where the Left Channel is much lower in volume than the right. The issue is a little strange in that the extent of the imbalance varies a lot and can be changed by quickly moving the potentiometer. Depending on the extent the issue can present as one channel being almost completely mute, or just a slight imbalance of the stereo image.

The issue remains in the same channel if I switch the valves, and if I switch the inputs (So I'm pretty sure that the problem is not in the valves or input wiring) and Voltages all check out as per the manual. Other than the channel imbalance the amp is silent, with no popping or hiss. I have attempted to poke all the joints with a chopstick and nothing presents as a bad solder joint.

So with that in mind I tried the nuclear solution, removing the main PCB and re flowing all joints (and by extension all the cables leading to it, however there was no change in the issue and this was pretty much a complete rebuild of the amp/)

So at this stage the only thing I have left is that the the pot may be faulty, and I will replace it as soon as I can. In the meantime though, I was wondering if there was anything else I can try. The was a previous post with a similar issue suggesting to check negative feedback and ground connections. However I believe I have addressed those with the rebuild, anything I've missed ?

Thanks in advance, Rob