I suspect that the terminology got confused because we all talk of speakers
being "in phase" when the cones are moving the same direction (at the same
time). The cone makes the sound wave by moving forward and back. As we
know, if two woofers are near each other, they can actually start
cancelling each other (not taking into account room nodes, etc.). We all
learned that we had to get the polarity right with the wiring, to keep the
speakers "in phase."
On Wed, May 6, 2015 at 9:05 PM, Dave Burnham <[log in to unmask]> wrote:
> Very well described, Richard!
> Sent from my iPhone
> > On May 6, 2015, at 8:31 PM, "Richard L. Hess" <[log in to unmask]>
> > Hi, Tom,
> > When measuring phase shift in degrees, it is relative to a given
> frequency. So, a 180 degree phase shift at 1 kHz would be the same time
> delay as a 360 degree phase shift at 2 kHz.
> > A polarity reversal is independent of frequency/wavelength. When it used
> to go up, it now goes down and vice versa. It is also a binary function: in
> or out of polarity.
> > I think 99% of the time when we say 180 ° phase shift, we mean polarity
> flip as we want it at all frequencies to be the same.
> > Cheers,
> > Richard
> >> On 2015-05-06 8:23 PM, Tom Fine wrote:
> >> So is it correct to say that there can only be a polarity reversal
> >> (180-degrees) whereas there can be any degree of phase shift?
> >> -- Tom Fine
> > --
> > Richard L. Hess email: [log in to unmask]
> > Aurora, Ontario, Canada 647 479 2800
> > http://www.richardhess.com/tape/contact.htm
> > Quality tape transfers -- even from hard-to-play tapes.