I have RAM in my RM-9 the ultr as low noise fronting the low noise
Mitchum or Blackburn for the Mullard 6922?
Do Mitchum production and Blackburn production sound different in the Mullard 6922? I believe I once read somewhere that Mitchum made tubes for the military, whereas Blackbutn did not, so, presumably, with better materials and/or tighter tolerances or testing.