Re: [ARSCLIST] Acoustic playback

[George Brock-Nannestad <pattac@xxxxxxxx>]

From: Patent Tactics, George Brock-Nannestad

Mike Richter wrote

> Steven Smolian wrote:
> > Karl's point about playing acoustic records back through the acoustic
> > machines on which they were intend to be heard is a good one.  However,
> > there are two arguments that torpedo it.

----- the rest at the bottom of the mail.

----- I think it was in 1989 that a comment on International Re-Recording 
Standards was published in the ARSC Journal. In it I proposed that the proper 
format to keep was that obtained by linear replay of the original record, and 
that any acoustic playback could be simulated by feeding this signal to the 
tip of a stylus of the soundbox of the acoustic "console" in question. 

----- as to the summing of distortions: Edison strived for a systems 
approach, i.e. weaknesses in the recording were compensated by the replay. 
Dayton C. Miller was a consultant to the Vocalion company, and although it is 
true that the mathematical treatment of the phonograph horn developed with 
Stewart and Webster from ca. 1920, Miller had made so many practical 
measurements of horns, varying all possible parameters, that he was very 
capable of consulting. I spoke about this at the ARSC convention in Cleveland 
2004.

----- all acoustic reproduction - direct from disc or via a linear transfer 
and a linear acutator as per above - will demonstrate some kind of authentic 
period sound - the quality and state of preservation will indicate the social 
status of the environment. However, it would not do for very much else.

----- as a further complication, if we really want period Victor sound, we 
should reproduce the records at 78 rpm, although they were recorded at 76 rpm 
for greater part of the acoustic period. I have documentary evidence (apart 
from measurements on the records themselves) that says that this discrepancy 
was intentional. Victor had found out that the records lasted longer that 
way. Which to me indicates that some resonances at reproduction were not 
placed where resonances were placed at recording - this would have increased 
the wear.

----- the Nimbus Prima Voce was a very sad advertizing stunt, because it did 
not do what they said it did. Their reproducer, using well-tuned EMG 
soundboxes and the best approach to an ideal horn since Edison's walk-in 
recording horn, was so linear and gentle to records that it would have 
demonstrated its capabilities properly with electric recordings. However, 
they chose to use acoustic records, which thereby demonstrated their full 
linear distortion (transfer function full of resonances and anti-resonances). 
Such records can be compensated by suitable filters, but that requires 
electronic reproduction.

----- Mike, I think that you should re-load your demonstration: we can never 
get enough reminding that there is a real world out there! At least I would 
enjoy it.


----- just a few postings away I shall have received 10,000 postings from the 
ARSClist since I joined. I shall post something about that later today, 
probably.

Kind regards,

George


Mike and Steven:
> > 
> > First is that what we hear is the sum of distortion introduced not only by
> > the playback horn and chain (tapered arm, etc.) but also that of the one or
> > ones used for recording as well as the characteristics of the recording
> > device.  The latter is, mostly unknowable at this stage.  It's the old issue
> > of problems being of a different magnitude where energy changes occur rather
> > than where they are amplified.
> > 
> > The other is that there was no mathematical understanding of the nature of
> > horns until the theory of matched impedance was uncovered in 1923 and
> > exploited in the design of the acoustical Orthophonic machines in 1924
> > (actual dates may vary by a year- I don't have my research data to hand.) 
> > Before then, all was guesswork- an "art" which led to varying degrees of
> > subjective sonic accuracy until then, none satisfactory, to these ears.
> > 
> > Steve Smolian
> > 

Mike Richter:
> Several years ago, I posted at my WWW site a demonstration of playback 
> using modern equipment and using my Columbia Phonola console. The latter was
> done with a variety of needles (steel, plastic, thorn) and with the pickup
> microphone at two distances from the player. The others were of conventional
> recording from the original disc and from two transfers to LP.
> 
> There is little question that ideal playback on the console had markedly
> different qualities from those of any of the modern approaches. All that one
> can say with confidence is that the sound from the console at its best was an
> ideal the publisher expected from the best equipment at the time of release.
> There is no way to say which is most accurate relative to the recorded
> performance.
> 
> I think it unlikely that the publishers even considered accuracy an 
> issue in acoustic recording. There would be little point to that 
> considering the effects of the artificial recording environment; 
> fidelity was not approachable, so was unlikely to be sought.
> 
> While listening through the console was a very satisfying experience, it had
> the drawbacks of damage to the disc and of sensitivity to room acoustic. There
> was a series of recordings on Nimbus under the title Prima Voce in which the
> recording was played on an excellent console in a large room to exploit room
> acoustics. A few discs showed superb results but most were muddied, some
> hopelessly.
> 
> If there's interest, I can re-post the page for those curious about the 
> results. It provides yet another demonstration of the variations induced in
> transferring/digitizing historic materials. Much more of the result depends on
> the transfer engineer than one would hope.
> 
> Mike
> -- 
> mrichter@xxxxxxx
> http://www.mrichter.com/