Lower power on left channel


Hi all, 

Does anyone have any ideas or come across this before?

I have a Primaluna Evo 300 pre-amp with a Primaluna Evo 400 power amp, using G/L KT 88 tubes. The other evening I was sat there playing some music and suddenly thought that it did not sound right, as I stood up and walked towards the centre of my speakers I noticed the the left speaker was down on volume compared to the right speaker. As I went to turn the system off I noticed that the KT88 tubes where down on heat to what they normally are.

I can not do much now till after Christmas but any help would be much appreciated

Merry Christmas 

Steve.       

128x128bigred71

If your tube sockets are marked left and right you could swap the tubes. When you listen again if the low power sound moves to the right, it would be your tubes. Also check connections. I guess I would swap left and right speaker cables to further check these circuits in the same way. Good luck.

+1 @2psyop  .  I don't know your preamp, but I have a Cary SLP 05 that uses 6SN7s, and using a specific test tone on a test CD I have used the AC volts setting on my meter to check volts at my speaker terminals, and I have found that depending upon which tubes I am using in my balanced input sockets, the readings are not always the same from L to R speaker.  I have found that when I then swap my L & R balanced input tubes, the readings I get follow the tubes.  

When I can get to the back of the amp I am going to change the speaker cables over and see if the loss of power is then on the right hand channel.