From: phil_a@tpg.com.au   
      
   "ZeeTso"   
   >   
   >   
   > what is confusing me is the fact that every 12AU7 datasheet says it needs   
   > 12,6V for heaters (in series).   
   >   
   > is this value absolutely necessary, or it might vary?   
      
   **  Anything from 11 to 14V is OK.   
      
      
   >   
   > p.s. original schematic is in pdf file here:   
   >   
   > http://www.fredsamplifiers.com.au/documents/12AU7_Valve_KIT.pdf   
   >   
      
   **  The AC adaptor is gonna be important.   
      
        If it has any hum you will hear it.   
      
      
      
   ...   Phil   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)