Dear Pat,   
   I read your article about Quad ESL and tube amplifier online. I've discussion   
   recently with my friends about stacking Quad ESL 57 and some even thinking to   
   stack 4 x ESL 57 in a big room and I'm interested in that since I have 2 in   
   stacking now.   
      
   They suggest wired in series for the stacking....and sent me this link:   
      
   http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1260720843&openflup&5&4#5   
      
   I wonder 3 ESL 57 stacking and series wired still ok since the impedance still   
   30 ohm range. However, 4 in stacking, no kidding the impedance will rise to 60   
   ohm and maximum can go up to 120 ohm on the low frequency.   
      
   Some even says 300B push pull can drive it!!   
      
   Gee...are they making a joke with me??   
      
   Regards,   
   JL   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)