XPost: alt.comp.os.windows-10, alt.home.repair, sci.electronics.design   
   From: eternal.september@ademu.com   
      
   On 2023-01-03 11:10, Clive Arthur wrote:   
   > On 03/01/2023 02:30, Brian Gregory wrote:   
   >> On 02/01/2023 13:48, Rink wrote:   
   >>> If you change the wires of one speaker you get a 180 degree   
   >>> difference on all audio frequencies.   
   >>> If from two speakers at the some radio (left and right), one is wrong   
   >>> connected, you can hear that at exactly the middle between the speakers   
   >>> where there is a fase-out for all audio frequencies.   
   >>   
   >> I've never heard an audible null between out of phase speakers. It usually   
   just ruins the stereo effect, makes it sound almost like two separate lots of   
   music (or whatever).   
   >>   
   > With a mono source (ie both channels the same phase) you lose a lot of bass   
   in the centre.  Block one ear and the effect is clearer and at higher   
   frequencies too.   
   >   
   > A long time ago, when stereo records were often mixed with the vocals in the   
   middle and other instruments to the sides, inverting one channel and adding it   
   to the other channel (ie subtracting it) could do a not-too-bad job of   
   removing the vocals for    
   karaoke.   
   >   
      
   Yesterday I tried to check if the internal pick-off from my new TV to better   
   speaker boxes was properly wired. Hard to hear. Left/right check was no   
   problem, but phasing was hard to hear (I'm deaf, -60 dB on one ear). Even with   
   a single speaker, and a    
   swept tone, I got dead spots from wall reflections.   
   An old trick solved the problem: put the two boxes very close, front to front,   
   and test with a mono signal. Improper phasing removes most of the sound,   
   proper phasing gives full volume.   
      
   Arie   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)