Reversing Polarity -- Voodoo or Easy Tweak?


In a recent thread I noticed a comment about reversing polarity of speaker wires on both speakers which sparked one of my earliest audiophile memories.

On the liner or cover notes of Dave Grusin: Discovered Again on direct to disc vinyl, circa 1977, it too recommended reversing the polarity on BOTH speakers, for best sound.

Although my first system was a 25 WPC Technics receiver with Infinity Qa's and lousy speaker wire, I still remember getting very enthusiastic about reversing the polarity and wondering if it did anything.

Can anyone explain this and/or recommend if this is even worth the experiment?
cwlondon
Herman...Both Hi and Lo signals are shifted 45 degrees at X/O, so the woofer/tweeter discrepancy is 90 degrees (for first order). In fact the discrepancy is constant at 90 degrees for all frequencies, but causes most problems around the X/O frequency where both drivers are emitting sound. With a second order crossover, 180 degrees of phase shift, there will be a deep sharp notch in frequency response unless one driver is connected with inverted polarity (or, as some might say, out of phase).That's why I like 24dB crossovers, where the shift is 360 degrees, so that sine waves are back in "phase" if you will pardon the term. Sine waves are a pretty good approximation of musical sounds, at least for a few cycles.
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so that sine waves are back in "phase" if you will pardon the term.

I know what you mean, in and out of phase just seems to sound right, and any use of the term polarity with a modifier seems to sound clunky and incorrect.

Both Hi and Lo signals are shifted 45 degrees at X/O, so the woofer/tweeter discrepancy is 90 degrees (for first order).

I think we are talking about 2 different things here. My point was that all musical instruments produce harmonics in addition to the fundamental tone. So if the fundamental falls inside the passband it will not be phase shifted and if a harmonic falls outside the passband it will be, or vice versa. I think this phase shift in the harmonic structure will be audible. I haven't conducted any experiments to confirm this hypothesis.
Well I am totally confused now. I just spent about 20 min listening to the CD of Jennifer Warnes, "The Hunter," track #8, "Way Down Deep". I listened to the first min and half at least 10 times then I reversed the speaker Cables at each of my ProAc studio 200 speakers. I then listened again several times. There is a definitely a difference in sound. I switched them back and forth several times.

On this particular track of this CD with the speakers cables reversed imo bass sounded tighter and Jennifer's voice sound more focused. Is it all in my head...

IF any of you have this CD check for yourself and post back.

Jim