ial-access.att.net> 50a35226   
   The 12by7a’s are most notably used in the Vintage Harman Kardon Citation II   
   tube amps.  They were designed with an extremely wide frequency range, due in   
   part to this tube’s capability.  They are also used in the HK Citation V, a   
   smaller version.  I    
   have two Citation II amps and have rolled most types of tubes through them   
   both, including Sylvania, GE, Phillips, RCA, the original branded HK supplied   
   tubes, some original Radio Shack gold plated tubes (that reveals my age) and   
   JAN (Joint Army/Navy)    
   military tubes.  They all have their own unique sound signature and so the   
   answer is determined by your preference, each is unique and its your own ear   
   that will decide.  I’ve read on other posts people like the RCA.  Also heard   
   original CBS tubes    
   sound good, but difficult to find.   I personally landed on JAN military tubes   
   because they are so rugged and have a balanced sound signature that seems to   
   gather in the best of the rest.  But they all sound good, just diffferent.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)