I rolled 6922's and experienced little change; however I rolled some 12au7's and experienced dramatic change. They were NOS 50's vintage, this was in a CJ.
Tube Rolling - No Change in Sound
In my Wyetech Opal pre, I substituted NOS Ken Rad VT231's for JAN Philips WGTA's in the input stage, expecting more body and warmth to sound based on Ken Rad reputation. But nothing has happened; I perceive no audible difference from the switch in tubes! What's up with this? This was my first foray into tube rolling.
Neal
Neal