The test consists of a 16-bit, 44.1 kHz mono WAV file about ten seconds
long. It was created using the waveform generator function of Cool
Edit. I inverted the polarity after about five seconds to simulate
the effect of reversing the polarity of a mic (switching pins 2 and 3 of
an XLR connector) or reversing the leads to both speakers.
Here's what it looks like:
During the original polarity portion, for a properly wired system, the speaker cone will move outward very quickly (the vertical line), then move slowly back to its original position (the slanted line). When the polarity switches, the cone moves outward slowly and moves back quickly.
Thinking about it this way, it's not surprising that the sound changes when the polarity is inverted, yet this is no different than swapping speaker wires, something that's usually thought to not matter.
Here's the test file. Download a copy, load it into any WAV file player or editor, and play it through any speakers you can reach with the signal. On three speakers here, including the Radio Shack Minimus 7's I have on my surfin' computer, the original polarity signal sounds more "bassy" than the inverted signal.
poltest.wav for MS-DOS systems
poltest.au for Sun systems
This (the master) site has been accessed times since the beginning of this year.
Drop me a note and let me know what you hear
Mike RiversMike Rivers (firstname.lastname@example.org)