From: luxaeternaaudio@gmail.com   
      
   Tube Rolling:-   
      
   Valves have certain specs, which all manufacturers of, say, an ECC83 adhere   
   to in terms of gain, bias sensitivity, mutual conductance etc. All   
   manufacturers have production spreads, so that a valve may have low gain,   
   another of the same type higher gain, but still within the acceptable   
   spread.   
      
   Is there any objectove evidence that a say, Mullard, ECC83 is any different   
   in spreads and performance than any other manufacturer's.   
      
   Is there any objective evidence that a say, Mullard, valve will sound any   
   different to another manufacturer's valve.   
      
   Is there any objective evidence that valve circuits are so sensitive to   
   changing valves unless it's clear that it's due to the valves being at   
   opposite ends of their production spreads.   
      
   How can one valve give better bass han another, given that all they're   
   doing is modulating DC, and the bass response is due to external components   
   anyway?   
      
   Or is it yet another audiophile myth?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)