Where to begin? With all due respect to Goran, I've been battling these
same misconceptions for three decades. I'll take it point by point.
On Thu, Feb 7, 2013 at 2:44 PM, Goran Finnberg <[log in to unmask]> wrote:
> Clark Johnsen:
>
> > There is no "correct" on tape, LP or CD -- because
> > there is no standard of reproduction that will yield
> > the proper result at the listener's ear.
>
> http://www.aes.org/publications/standards/search.cfm?docID=28
>
Yes. BUT there is no means in that (faulty) standard to, as I wrote, "yield
the proper result at the listener's ear". Nor do the various outfits that
are responsible for our recordings much care, else LPs and CDs produced
since that so-called standard was adopted in 2005 would not vary so
tremendously in electrical polarity.
>
>
> -------------
>
>
> May I point out that Microphones, Mixers, Analogue Tape machines, Digital
> tape machines, Disk cutters and pickups, Loudspeakers must all adhere to
> correct RELATIVE polarity in/out.
>
"MUST" -- by what authority? (Of course, there is none.)
>
> If not then the extensive manipulation of audio processing would not be
> possible to do.
>
But it's done anyway, and one of a mixer's options is to put a stem or
stems out of phase with the others, deliberately.
>
> ABSOLUTE polarity meaning positive polarity giving positive polarity output
> can be seen in microphones since the 30/40īs.
>
NO! This is key to grasping the situation. There's plain old polarity
(electrical polarity) and then there's Absolute Polarity (acoustic
polarity). Tapes etc. inscribe the former, while acoustic polarity is at
the listener's discretion. It's a useful and necessary distinction.
>
> Mixers too at every in/out point if not they would be unusable since one
> would get cancellations when trying to mix music through the equipment.
>
Only with mono signals. There's enough phase spread in stereo/multi mikings
to allow any combination without cancellation.
>
> Analogue tape machines are all correct in/out
Must beg to differ. Just for starts, the EIAJ (Japan) convention is
different from Europe and USA.
After Sony acquired MCI, at that time the largest manufacturer of studio
tape recorders, it switched the mic input hotsides without notification to
previous users. Imagine the confusion.
> BUT the exact polarity as
> recorded on the actual tape was not standardized until the 80īs.
>
Dreamer!
But at least Stodolsky had proposed a polarity convention back in 1970, in
the IEEE Transactions on Audio.
>
> Digital equipment has been correct since the dawn of digital, 1982.
>
Not by the (informal) surveys I've conducted.
>
> Neumann and Ortofon cutters both adhere to the correct polarity that should
> be cut on vinyl disks.
>
Yes, "the" convention for LPs. Question: Does an outward-going groove
excursion produce a positive-going signal or a negative? Answer: Depends,
are you cutting in America or Japan?
>
> Most pickups follow the vinyl disk polarity convention since the 70īs.
>
Yes and no. The vast majority do actually have the same polarity response
to a test signal. But that's unrelated to the polarity of the inscribed
signal.
>
> Most loudspeakers have at least the red binding post when fed a positive
> pulse having the BASS speaker move forwards for a positive increase in
> front
> of the speaker.
>
The JBL example to the contrary has already been mentioned. Also, with so
many loudspeaker designs having the midrange driver wired out of phase with
the top and bottom, how does one determine?
>
> BUT if a three way speaker uses 12 dB/octave cut off butterworth filters
> then for flattest FREQUENCY response then the polarity becomes LF + MF - HF
> +.
>
Aha! I should have read ahead.
>
> Using 24 dB Linkwitch-Riley filters where the filter are IN phase in the
> crossover band we get LF + MF + HF + so the whole speaker is in the correct
> polarity.
>
NO! In the electric domain it's at least a consistent presentation, a step
in the right direction, but that's still no guarantee that the acoustic
signal emanating from it will be in the correct acoustic polarity.
>
> I would claim that since the 80īs MOST recordings have the polarity correct
> including the final release media as CD 44/16.
>
The misuse of "polarity correct" notwithstanding, I will bet you any amount
you care to name that I can find at least a 35% variance of polarity on CD.
In fact my research has found even more, but let it pass, let it pass.
>
> What the consumer market does is an entirely different matter BUT most of
> the time the equipment is in the correct polarity convention.
>
Dreamer!
>
> I have Vinyl test disks with polarity test signals.
>
So do I. And there's at least a 2:1 variance among them.
>
> And several CD test records with polarity test signals.
>
Ditto the above. It's a scandal.
>
> http://www.smartdevicesinc.com/ezphase.html
>
Yes. But this is a closed-loop device; it provides the test signal and the
microphone and the analyzer, but it's not designed for music signals.
Ironically, the one review the site references begins thusly: "Previously,
in a couple of my articles, I have discussed the importance of Absolute
Polarity and the seminal work on this by Clark Johnsen in his book The Wood
Effect."
>
> And there is lot of testing devices for polarity out there in the shops.
>
Perhaps, but again, they are closed-loop. And by the way, all you need to
test louspeaker drivers this way is a 6v. battery.
>
> I, personally, bought my first polarity tester from the German company EMT
> in the early 70īs and this tester can measure both
> microphones/loudspeakers,
> amplifiers, cables etc with no problems.
>
Piece'a cake, granted. Now what about music? It comes divided willy-nilly
between the two electrical polarities, so what device will distinguish them?
clark
>
>
>
>
>
> --
> Best regards,
>
> Goran Finnberg
> The Mastering Room AB
> Goteborg
> Sweden
>
> E-mail: [log in to unmask]
>
> Learn from the mistakes of others, you can never live long enough to
> make them all yourself. - John Luther
>
> (\__/)
> (='.'=)
> (")_(") Smurfen:RIP
>
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