Help! 3 channel DR volume cutting down

[billelzebub]

I have a 3 channel dual rectifier. I'm having a problem with volume loss in channels 2 & 3. After about 15 minutes I experience a volume drop out. Sometimes it drops down for a bit then boosts back up, sometimes I need to switch back n forth between another channel and the volume returns. It's not a fade down, it's a straight drop. I switched out all the pre amp tubes and problem was still there. Switched out the power tubes, problem still there. Switched from silicon diode to tube rectifier, problem still there. Switched out speaker cables, problem still there. So I'm at a loss as to what the problem is. Has anyone else experienced this problem? I have another 3 channel DR and it doesn't do this. I've also owned a 3 channel triple rec and two 2 channel DR that never had this problem. Any help/insight would be greatly appreciated. Thanx!

 

[espboogie123]

Make sure you have chinese or non-russian tubes in your v3 and v4.

 

[AudioMonk]

Hello. This problem is caused when the coil inside one of the relay's for switching can no longer holds it's charge in order to keep the channel switched and signal held to appropriate level. This is why when you switch back, it goes on temporarily due to the coil inside the relay charging and holding again.

 

[billelzebub]

Thank you audio monk! I will tell the guys at the amp shop about this when I take it in. You may have saved me alot of money in repair cost.