From: phil_a@tpg.com.au   
      
   "Phil Allison"   
      
      
   > ** The AR9 was first sold in 1978 and used two 12 inch woofers, same ones   
   > used in the AR11 released in 1977.   
      
   ** AR constantly refer to the above woofers as being 12 inch.   
      
   But they are closer to 11 inch, in reality.   
      
   I remember now there was something odd about the woofers in a friend's   
   AR11s.   
      
   The impedance curve of the AR11 was so wild I drew it out and kept a copy -   
   here is a listing:   
      
   DC       =    4.2 ohms   
   10Hz    =    5 ohms   
   32Hz    =  30 ohms   
   100Hz  =    4 ohms   
   500Hz  =   10 ohms   
   1kHz     =   4 ohms   
   2kHz     =   2.5 ohms   
   5kHz     =   2 ohms   
   10kHz   =   2 ohms   
   12kHz   =   2 ohms   
   20kHz   =   3 ohms   
   50kHz   =   8 ohms   
      
   BTW:   
      
   The low figures above 2kHz are because the 4ohm dome mid and 4ohm dome   
   tweeter are operating in parallel.   
      
   The owner was originally using twin wire he got from Tandy / Radio Shack (   
   14x0.14 stuff ) -  so each run was about 1.5 ohms resistance, plus about 2.5   
   ohms of inductance at 15kHz.   
      
   So I made him up some leads using "Tocord" ( aka Mogami cable)  with near   
   zero inductance and about 0.2 ohms resistance.   
      
   His mouth dropped open when he heard the difference.   
      
      
      
   ...  Phil   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)