From: pallison49@gmail.com   
      
   Jasen Betts wrote:   
      
   >   
   >   
   > Play an asymetical signal. One that does not have glide reflection   
   > symmetery, eg: 33% PWM  use a low low frequency so that the cross-over   
   > doesn't mess it up too much.   
   >   
   > view the sound on an oscilloscope (or audacity etc)   
   >   
      
   ** Make current pulses in each speaker using a battery, 1.5 V to 6V.   
      
   Use a mic or small speaker attached to a pole and view output on a scope.   
      
   The resulting asymmetrical sound pulses will be the same polarity when the   
   wiring is correct.   
      
      
   ....   Phil   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)