This is a critical can of worms. Consider the facts, Ma'am. Without consistent and foolproof power supply, supplied to the actual signal path, how can we expect anything close to the perfection of sound we all strive for?
I just switched out the Ruby 5AR4 for my treasured Mullard military CV378 (GZ37) in my recently-acquired ST-120. Not changing any other levels or settings, I do believe that I hear a palpable decrease in harshness. This when listening to a fairly well-recorded Mozart symphony.
I believe that Weber has, more than likely, experienced an increase in customer complaints which may be due to a loss of control over components, or a simple laxity in quality control, which may indeed lead to a crash.
Caveat emptor, and all that poop.
Any and all precautions are advised.
Last edited by Kentley on Thu May 14, 2015 7:19 am; edited 1 time in total (Reason for editing : Tube misidentification due to incipient Alzheimer's.)