Thanks again,   The first thing we did was swap the tubes left to right and the crackle stayed in the right channel.  Still think its the tubes?   I am not bored by the link, just totally bewildered!  I will send it to my tube amp guru.   PSRyan Neophyte

Thanks,   Well he was horrified, and cleaned up a bunch of stuff but he didn't find the problem.  The tubes tested OK.   Shall I just buy the "upgraded" tube types Mikhail sent or is there some magic formula of tubes you would recommend?   The tubes have run 2-3 hours per day, every...

My Singlepower ES-1 Amp (with HE-90) crackles only in one channel with or without source and it is intermittent.  Actually it comes and goes for days at a time and is very hard to duplicate on demand.  If I unplug the power supply for a day it will usually behave for a few days.   I know...

I'm new to this forum, but not new to Mike Oldfield. TB I was movie music to me. Scary movie...the Exorcist. TBII was an incredible find. Like someone else I heard it playing in a music store. Hooked by the repeated references to TB I, I found much more and must have listened to it 500 times...