[Table of Contents]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [ARSCLIST] Fwd: Peter Copeland on RCA Victor recordings (1941)

You can hear that Victor was doing compression/limiting for sure by the 40s. Listen to Spike Jones "Popcorn Sack" for instance, or other material if you prefer less corny. In a studio of those days, it would not be un-surprising to have an 8' rack of limiter units, one for each of the few mixer positions. I agree with whomever said the limiter would have to come after a mic preamp because Victor probably used RCA ribbon mics in those days. When high-output European condenser mics came along in the 50's, one of the key mistakes engineers made -- and this is especially audible in jazz recordings of the era -- was to put something like a U-47 close in on a piano or drum and feed it into a mic preamp designed to expect ribbon output levels. Distortion from the get-go results (ie a lot of early Van Gelder recordings, and others). Roy DuNann out at Contemporary figured out that these high-output European mics he was using could be imedence-matched right into a passive mixer, which put out about dynamic or ribbon mic level at the end and fed into an Ampex 350 mic input. His recordings do not suffer fuzzy drums and bass and piano. Anyway, back to Victor, yes very clearly audible compression is present on some late-era 78's.

-- Tom Fine

----- Original Message ----- From: "Prentice, Will" <Will.Prentice@xxxxx>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Friday, October 03, 2008 8:18 AM
Subject: Re: [ARSCLIST] Fwd: Peter Copeland on RCA Victor recordings (1941)

I've asked some of Peter's former research colleagues what his sources of info on Victor's use of limiters might have been, and had the following response from Adrian Tuddenham:

"No obvious written source of that information comes to mind.

From Blumlein's days in audio (if not before) the idea of a
self-limiting recording system without audible defects was a bit of a
'holy grail'.
Blumlein experimentd with reducing the field in the WE cutterhead to
counteract 'blasting' distortion from the inverse-square force which the
moving iron armature experienced on amplitude peaks (the idea was
abandoned because it could not be made to respond quickly enough).  I
remember Peter commenting that it was impossible to overmodulate a
Blumlein moving coil cutterhead and the amplitude limit was usually set
by the geometry of the grooves and the limitations of the playback

Peter's ear was incredibly sensitive to limiting (whether by machine or
by hand) and he could often unequivocally hear it when I didn't notice
it or was in some doubt.  It is possible that he simply derived this
information from listening to the discs.  I have no doubt that he would
not have made a statement like that unless he could quote the evidence
if challenged - and if the evidence were audible, I don't think there
would be much doubt that he would eventually be proven correct."



-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:ARSCLIST@xxxxxxx] On Behalf Of Doug Pomeroy
Sent: 01 October 2008 14:39
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: [ARSCLIST] Fwd: Peter Copeland on RCA Victor recordings (1941)

From: Doug Pomeroy <pomeroyaudio@xxxxxxx>
Date: September 30, 2008 8:51:10 PM EDT
To: 78-list <78-l@xxxxxxxxxxxx>
Subject: Re: Peter Copeland on RCA Victor recordings (1941)


I only mentioned that issue of Wireless World, because it is
Ref. 60, which he identifies at the head of the paragraph which
the statement about Victor's use of limiters.  Thanks for checking.


Date:    Mon, 29 Sep 2008 15:14:11 -0400
From:    Michael Biel <mbiel@xxxxxxxxx>
Subject: Re: Peter Copeland on RCA Victor recordings (1941)

Prentice, Will wrote:

Doug and all

I've looked up this edition of Wireless World, but there's no
mention of
Victor's use of limiters I'm afraid. It's a short, 3 paragraph
entitled "New Recording Characteristic: Reducing Noise Level"
in general terms the idea behind pre-emphasis.

I think the key word here is the use of the word "level" in the headline. Since limiters adjust level, could he have misinterpreted it to mean that this EQ was adjusting levels? As we know now, a pre-emphasis properly works only if there is a calibrated reciprocal de-emphasis on the playback end. Consumer phonographs did not have actual de-emphasis circuits at that time, only professional turntables in broadcasting had them for the newly emerging Orthocoustic and NAB curves. Unlike Dolby and DBX, these units were completely passive. Was Peter possibly claiming that RCA was using limiters as an active EQ, several decades in advance of Dolby? And what was the 1941 Wireless World article detailing? Orthocoustic had been announced back in 1938 for ETs. Was this a curve being used on commercial phonograph records or a belated article on Orthocoustic?

I don't recall discussing this with Peter, but others he worked
with on
a wider level may know his sources. George Brock-Nannestad,


I agree.  George, have you seen anything in the EMI papers that

Mike Biel mbiel@xxxxxxxxx

-----Original Message-----
From: Doug Pomeroy

The following from Copeland's manual has always puzzled me, and I
if anyone can shed light on the reference to "Victor's then-unique
use of multiple
limiters (essentially one on each mike)", since I've never heard of
this from any other
source.  This may originate in Ref. 60, Wireless World (1941), which
I have not
seen.  RCA Victor may have experimented with limiters in 1941, but
statement can leave the impression that this was common practice.

6.71 Various RCA characteristics
Ref. 60 (July 1941) is the earliest contemporary reference I have
found which describes RCA Victor using pre-emphasis on its 78s,
although the time constant was not given. Straight listening
suggests the idea was tried somewhat earlier, and we saw in section
6.23 that Moyer wrote about RCA's Western Electric systems with
emphasis at 2500Hz (corresponding to 63.6 microseconds); but I am
deeply sceptical. It seems to me far more likely that, if something
which had been mastered direct-to-disc was reissued on microgroove,
the remastering engineer would simply have treated everything the
same. And I consider it likely that judging by "pure sound" clues,
Victor's then-unique use of multiple limiters (essentially one on
each mike), would itself have resulted in a "brighter" sound.

Doug Pomeroy


Experience the British Library online at www.bl.uk

The British Library's new interactive Annual Report and Accounts 2007/08 : www.bl.uk/knowledge

Help the British Library conserve the world's knowledge. Adopt a Book. www.bl.uk/adoptabook

The Library's St Pancras site is WiFi - enabled


The information contained in this e-mail is confidential and may be legally privileged. It is intended for the addressee(s) only. If you are not the intended recipient, please delete this e-mail and notify the postmaster@xxxxx : The contents of this e-mail must not be disclosed or copied without the sender's consent.

The statements and opinions expressed in this message are those of the author and do not necessarily reflect those of the British Library. The British Library does not take any responsibility for the views of the author.


[Subject index] [Index for current month] [Table of Contents]