I don't see how polarity reversal is at the same time, John. When the polarity is reversed, the two signals are 180 degrees out of phase. The negative peak in one channel is taking place at the same time as the positive peak in the other channel. That's why they cancel, given that the sine wave signals are equal in amplitude. In a polarity reversed two-channel comparison, say using 1 kHz sine wave, one channel is 0.5 msec delayed from the other channel [half the period].
Ron Roscoe
-----Original Message-----
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of John Haley
Sent: Wednesday, May 06, 2015 3:39 PM
To: [log in to unmask]
Subject: Re: [ARSCLIST] Playing Edison Diamond discs
I don't think so, Ron. Real phase shift means along a timeline--out of phase means not time-aligned. Polarity reversal is at the same time.
Best,
John Haley
On Wed, May 6, 2015 at 3:35 PM, Ron Roscoe <[log in to unmask]> wrote:
> Oi! Phase, polarity...........
> Polarity is just a special instance of phase shift; 180 degrees!
>
> Ron Roscoe
>
> -----Original Message-----
> From: Association for Recorded Sound Discussion List [mailto:
> [log in to unmask]] On Behalf Of Jamie Howarth
> Sent: Wednesday, May 06, 2015 3:32 PM
> To: [log in to unmask]
> Subject: Re: [ARSCLIST] Playing Edison Diamond discs
>
> Correct, and I'm talking about phase because the two grooves are never
> perfectly perpendicular.
>
>
>
> Please pardon the misspellings and occassional insane word
> substitution I'm on an iPhone
>
> > On May 6, 2015, at 3:25 PM, DAVID BURNHAM <[log in to unmask]> wrote:
> >
> > Actually, Mickey, Pete is correct. What you are describing is
> > polarity
> reversal, as Michael Biel is usually only to happy to discuss.
> >
> > Dave
> > --------------------------------------------
> > On Wed, 5/6/15, Mickey Clark <[log in to unmask]> wrote:
> >
> > Subject: Re: [ARSCLIST] Playing Edison Diamond discs
> > To: [log in to unmask]
> > Date: Wednesday, May 6, 2015, 1:43 PM
> >
> > Pete-Phasing is inverting the
> > waveform - no delay temporally-Mickey Follow me on Twitter
> > https://twitter.com/MickeyRClark M.C.Productions Vintage Recordings
> > 710 Westminster Ave. West
> >
> > Penticton BC
> > V2A
> > 1K8
> > 1-250-462-7881
> > http://mcproductions.ca
> > ----- Original Message -----
> > From: "Pete Tinker" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Wednesday, May 06, 2015 8:51 AM
> > Subject: Re: [ARSCLIST] Playing Edison Diamond discs
> >
> >
> >> Please forgive this uneducated question. Much of
> > the discussion on this
> >> topic has focused on the "phase" of different
> > transfers. I'm not a
> >> signal processing guy, but to me "phase" involves the
> > frequency of the
> >> signal, so changing the phase is a temporal shift in
> > the signal (a
> >> lateral shift along the time axis) by a fraction of
> > some wavelength. At
> >> times in this discussion, it seems that the intention
> > of changing the
> >> phase is a reversal of the amplitude of the digital
> > signal (mirroring it
> >> across the time axis), for which frequency is
> > irrelevant.
> >>
> >> If I have a stereo signal from a hill 'n' dale source,
> > it seems the
> >> preferred next step is to invert the phase of one
> > channel and then
> >> combine (add) the two channels prior to any digital
> > noise reduction.
> >> What is the meaning of "phase" in this context?
> >>
> >> --
> >> *Pete Tinker*
> >> West Hills, CA 91307
> >> 818-three/four/six-5213
> >> 818-six/nine/four-5213 /(cell)/
> >
> > ---
> > This email has been checked for viruses by Avast antivirus software.
> > http://www.avast.com
> >
>
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