Best Procedure to Chase Down Noisy Tube

[CJinSC]

What do y'all find is the most efficient way to ferret out a noisy tube in a pair of LP140's? I have some low level distortion that seems to come & go in the right channel.
I normally power off all my equipment when changing tubes. Is this necessary? Or can I just turn off the right amp & change tubes & power it back up while leaving the left amp & preamp powered up.
Thanks fellas & have a great Thanksgiving for those in the states!
John

[pstrisik]

The easiest way for me is to simply swap one tube at a time. You could do it between amps (swap tubes from the same position to keep track) and see if the problem switches channels.

I don't think there is a problem just turning off the amp to swap tubes while leaving the preamp on - I've done that. The caution is generally about making sure speakers are connected when you turn amps on.

[CJinSC]

Thanks Peter