Playback equalization for 78 rpm shellacs and early 33⅓ LPs

The audio on almost every phonograph record is not the same as that originally performed. For technical reasons the signal's frequencies need to be modified when cutting the disc. Playback equalization (EQ or de-emphasis) is necessary to restore the signal's original frequencies. Only thus can music lovers enjoy the original sound of the music performed long ago from their rare discs.

Usage

The most relevant EQ curves are presented as Table 1:

Which EQ curve will be needed for a specific record label is answered:

Using EQ curves in Audacity

Once converted to txt, you can import the curve in the Filter Curve EQ or Graphic EQ effects, by clicking Presets & settings -> Import....

Equalization (EQ) Curves explained

When phonograph records are made, the sound being recorded is deliberately distorted by reducing the volume of the low frequencies and increasing the volume of the high frequencies. This process, known as 'pre-emphasis', allows the low frequencies to be accommodated in the limitations of the record groove and reduces the effect of high frequency surface noise. If pre-emphasis was not carried out, the bass notes in the music would create a groove in the record that oscillated so wildly that the stylus could jump out of it on playback, and the treble notes would be drowned out by the surface noise of the stylus in the groove.

On playback, the pre-emphasis must be reversed in order to restore the original sound. This is known as 'de-emphasis' or equalization (EQ).

Modern vinyl records use a method of pre-emphasis and de-emphasis adopted by the Recording Industry Association of America (RIAA) in the 1950's, and the EQ curve used is known as the RIAA curve. However, before the RIAA curve was adopted, each record label used its own EQ curve for recording and, for these records (78rpm and early vinyl), the correct EQ curve must be used for playback.

Each EQ curve is a combination of two filter characteristics; a bass boost curve, defined by a 'Bass Turnover' (or 3dB) frequency, and a treble cut curve, defined by a '10 kHz Gain Roll-off' parameter, i.e. a defined level of treble cut at 10 kHz.

As an example, Figure 1 below shows the characteristic of the bass boost curve defined by a 500Hz Bass Turnover, and Figure 2 shows the characteristic of the treble cut curve defined by a 10 kHz Gain Roll-off of -13.7dB. These two curves, when combined, give the characteristic shown in Figure 3.\

The EQ curve may also include a Low Frequency Shelving filter, (although it is absent from the definition of most 78 rpm EQ curves). This addition reduces the effect of the bass boost at very low frequencies (typically 50 or 100 Hz) in order to attenuate low-frequency noise such as turntable rumble. Figure 4 shows the effect of a 50 Hz LF shelving filter being added to the curve in Figure 3. This is in fact the RIAA standard EQ curve.

Acoustically recorded (pre-electric) 78 rpm records have a completely different characteristic because they were cut with a different type of cutter (For more details see: Acoustic recordings). In some early EQ curves of electrically recorded shellacs, while there is a bass boost curve, there is no treble cut necessary – i.e. the 10 kHz gain roll-off is zero.

Note that in the combined EQ curve, the gains at the Bass Turnover frequency and at 10 kHz may be different from those specified by the parameters. This is not an error, but is due to fact that the gains of the bass boost and treble cut curves are simply added together.

Because 78 rpm EQ curves were non-standard and, in many cases, accurate records were not kept to show what EQ curves were used when recording 78s, there is a degree of uncertainty about what is the correct playback EQ for many record labels. The tables below have been obtained from websites which, in their turn, have compiled data from a number of sources and should prove reasonably accurate. However, the ear of the listener is the final arbiter - if it doesn't sound right, it isn't right!

According to NAB standards, the nominal speed of a 78 rpm record is precisely 78.26 rpm +/- 0.3% (for North America and other countries with an utility frequency of 60 Hz). According to British Standards Institution it is 77.92 rpm +/- 0.5% (for Britain, Europe and other countries with a mains frequency of 50 Hz).

EQ Curves

Pre-equalization of most records – especially of shellacs – was always determined by the cutter head used and often by internal regulations of the record company. Both left quite some room for the recording engineer to make changes to improve the sound. Also if Graumann uses 250 Hz in playback of an EMI disc and Copeland votes for 300 Hz this is not a contradiction. Both mean the same EQ curve but have different opinions on what sounds best. This should encourage you to try both versions and take the one which sounds right to your ears.

Please do not worry about fractions of a dB! Still in the 1960s an accuracy of a curve of +/- 2 dB was considered to be standard. In the 1950s +/- 3 dB were a very fine result and nobody will ever know if recording engineers in the 1940s or 1930s applied their curves correctly (or if they applied them at all!) So the spread in pre-equalization during recording will outnumber any bias in playback equalization by far.

Table of EQ Curves

The most relevant EQ curves are presented in Table 1. All curves are described from the point of view of a playback or de-emphasis curve, where bass / low frequencies must be amplified / boosted and where treble / high frequencies must be attenuated / cut in order to achieve the original sound that had been recorded. The corresponding pre-emphasis curve used for cutting the master disk is inverse.

When comparing with lists provided by the manufacturers of equalizer pre-amps it should be considered that those may be misleading, as they might not quote the correct parameters of the curve but rather the next-best possible settings of these devices. For example the Conductart OWL 1 Sound Restoration Module – a renowned pre-amp of the 1980s – offered settings of flat/ 250/ 375/ 500/ 750/ 1000/ RIAA for turnover and flat/ 5/ 8.5/ 12/ 14/ 16/ RIAA for roll-off. Thus for the widely used standard “AES 400N-12” settings of 375 Hz and -12 dB were listed; for the “Bartok 629C-16” curve it was 750 Hz and -16 dB and for “LONDON LP 500C-10.5” it was 500 Hz and -8.5 dB. These recommendations were quoted or copied by other authors and three “new characteristics” had come to existence.

Table 1 gives the three parameters to characterize any EQ curve: the turnover frequency f1 for bass shelf, f2 for bass boost and f3 for treble cut (or alternatively the three corresponding time constants τ1, τ2 and τ3). These are the necessary conditions to compute and plot any EQ curve, determine the correct settings of a digital equalizer or to solder an electronic filter circuit.

The gain at two typical frequencies will give you a rough impression of what the curve does to the audio from the record. The frequencies are:

  • 50 Hz, where usually the bass shelf becomes effective

  • 10 kHz, because the treble curve is often indicated by roll-off at 10,000 Hz

The very descriptive “code” is a good tool to avoid misunderstanding when EQ curves come under various alias names (what they do too often).

  • The first 3-digit number indicates the turnover frequency of bass boost (f2)

  • The letter in the middle is N … (“None”) if no bass shelving is applied, or R … 20 dB (named R after RCA or RIAA) B … 18 dB A … 16 dB C … 14 dB (named C after Columbia LP curve) X … 12 dB

  • The last number shows the reduction or roll-off of treble at 10 kHz and is always preceded by a minus sign. Please mind that this is only a code and that the exact value – after normalization to 0 dB at 1000 Hz – might be different.

This code can be used to find the correct settings of most equalizer pre-amps.

(Example: “RIAA 500R-13.7” means for the RIAA curve that bass must be boosted below 500 Hz, but no more than + 20 dB and that treble must be cut at 10,000 Hz to – 13.7 dB)

The geographic region and the time period are added to allow a qualified guess for the required EQ should a record label not be listed. In general, American recording curves were more deliberate in cutting bass and boosting treble. The British and Europeans tended to apply only the necessary minimum of bass attenuation and often no treble boost at all, that means they had a “flat” treble curve. Early pre-emphasis curves were simply built and rather soft. In the late years (after 1945) curves became highly sophisticated, with the third turnover frequency f1 added to manage the bass shelving and also with gain ranging from -20 dB to + 20dB.

Table 1: Playback Equalization Curves

Region
Timeperiod
Curve Name, alias names
Time constants
Time constants
Turnover frequencies
Turnover frequencies
Turnover frequencies
Bass shelf
Bass boost
Treble cut

τ1 [μs]

τ2 [μs]

τ3 [μs]

f1 [Hz]

f2 [Hz]

f3 [Hz]

[dB]

@ 50Hz [dB]

@10kHz [dB]

Normal Groove, 78 rpm

Eur., Brit.

1926 - 1946

"European 78", Old Europ.,250,EMI 78

636

250 [5]

+ 14,4

0 (flat)

250N-0

Eur., Brit.

1927 - 1946

"Blumlein 300"

531

300 [5]

+ 16

0 (flat)

300N-0

Brit., Amer.

1926 - 1950

"500-FLAT", Blumlein500, Europ.500

318

500

+ 19

0 (flat)

500N-0

America

1926 - 1951

"American 78"

636

250

5900*

+ 14

- 6

250N-6

America

1926 - 1951

"American 78"

636

250

4400*

+ 14

- 8

250N-8

Amer.(CBS)

1938 - 1948

"Columbia 78"

530

100

300

1592

+ 16,7

- 15,0

300N-16

Amer.(RCA)

1941 - 1947

"Old RCA" [4]

199

36,7

800

4340

+ 22,2

-9,9

800N-8

Eur., Brit.

1944 - 1956

"DECCA 78", FFRR 78, London ffrr 78

531

25

300 [5]

6366

+ 15,4

- 5,7

300N-5.5

Germany

1952 - 1955

"CCIR 78", Recomm. No.134 (1953) [1]

450

50

354

3183

+ 17,0

- 10,5

350N-10.5

Eur., Brit.

1955 - end

"IEC N78" = "B.S.1928" for N78 only

3180

450

50

50

354

3183

+ 16

+ 14,0

- 10,5

350A-10.5

Microgroove, 33⅓ and 45 rpm

America

1942 - 1949

NAB (broadcast transcriptions, 1942)

318

100

500

1592

+ 20,5

- 15,6

500N-16

America

6/1948 - 1956

"Columbia LP", Col. M33, "LP" [3]

1590

318

100

100

500

1592

+ 14,5

+ 13,6

- 15,5

500C-16

America

4/1949 - 1958

"NAB", NARTB (standard 1949) [3]

3180

318

100

50

500

1592

+ 20

+ 17,5

- 15,6

500"B"-16

America

1/1951 - 1958

"AES" (standard 1951)

398

63,7

400

2500

+ 18,1

- 12,3

400N-12.3

Amer.(RCA)

1947 - 8/1952

"RCA 45" (45 rpm) [6]

200

75

796

2122

+ 22,6

- 13.7

800N-13.7

Amer.(RCA)

1947 - 8/1952

"RCA Old Orthophonic" (33⅓ LPs) [6]

318

75

500

2122

+ 19,7

- 13.7

500N-13.7

Amer.(RCA)

8/1952 - pres.

"RCA New Orthophonic"

3180

318

75

50,05

500,5

2122

+ 19,5

+ 16,9

- 13,7

500R-13.7

Amer. (all)

ca.1956 - pres.

= "RIAA" (US-standard since 1955)

Europe

ca.1962 - pres.

= IEC No.98 (1955) = B.S.1928 (1955)

Amer., Brit.

1949 - 1956

"LONDON LP" [2]

1590

318

50

100

500

3183

+ 13,8

+ 12,5

- 10,9

500C-10.5

Germany

1955 - 1962(?)

TELDEC (as proposed 1957 for DIN)

3180

318

50

50

500

3183

+ 19,3

+ 16,5

- 10,9

500R-11

Citations

Table 1 is mostly based on Tab. 2a of: Heinz O. Graumann, Schallplatten-Schneidkennlinien und ihre Entzerrung, in: FUNKSCHAU 1958 / Heft 15, pp 359 ff* computed frequencies to get 6 or 8 dB @ 10 kHz

[1] CCIR used by Deutsche Grammophon modified with 50 Hz bass shelving => IEC N78 [Brice]

[2] Used by British Decca and for London releases in US and UK, mostly M33. Cf.: Wolfgang Leister, The London Curve, in ARSC Journal, vol.48:2, Fall 2017, p.163

[3] Gary A. Galo, The Columbia LP Equalization Curve, ARSC conference March 2008; Gary A. Galo, Disc Recording Equalization Demystified, in ARSC Journal Fall 1996

[4] Old RCA is one of the original RCA curves for shellacs. It continued to be used for 33⅓ LPs by RCA-Victor, Brunswick, Concert Hall, Coral, Decca (Amer.) and Westminster. The turnover f3 and the time constants are computed values for an equalizer set at 800N-8.

[5] 250 Hz or 300 Hz seem to be a question of personal listening preference, as explained in Individual fine tuning

[6] Robert C. Moyer, Evolution of a Recording Curve; in: Audio Engineering, vol.37, no.7, July 1953; pp 19-22, 53-54. Roll-off is frequently listed as between 10 and 12 dB, but this “flattening off” to ca 10 dB at 10 kHz was an intentional high cut which must not be compensated for in playback. Thus a setting of 13.7 dB is correct!

78 rpm EQ Curve Generator

EQ Curves for Audacity can be generated from these Frequency and Roll-off values using the experimental Nyquist plugin "78 RPM EQ Curve Generator". This plugin is obtainable from the top of this Forum topic and requires Audacity 1.3.13 or later. Please give feedback on this plug-in, or ask for help if you need it, by replying to that Forum topic.

  1. Extract 78EQCurveGen.ny from the zip file downloaded from the above Forum topic.

  2. Place 78EQCurveGen.ny in the "Plug-Ins" folder inside the Audacity installation folder, then launch or restart Audacity. For more help installing the .ny file to the correct location, click here.

  3. Click . You can find help inside the plugin by choosing one of the Help options in "Select Function or Help".

  4. Choose the curve you want from one of the lists.

  5. Enter the values for your chosen curve for

    • "Bass Turnover Frequency (Hz)"

    • "10 kHz Gain Roll-off (dB)"

    • "LF Shelving Frequency (Hz)" (if a value is given)

    in the equivalent boxes in the plugin dialog.

  6. Click "OK" in the plugin to save the .xml file to your chosen location.

  7. Use the EQ XML to TXT Converter Tool to convert your XML file to a TXT text file (suitable for Audacity 2.4.0 and later)

  8. Select some audio and choose .

  9. Choose "Manage".

  10. Choose "Import...", navigate to the location where you saved the .txt file.

  11. Click "Open".

EQ Curves Library

Here you can find some useful EQ curves for download to Audacity for use in Effect -> EQ and Filters -> Graphic EQ and Filter Curve EQ. (Curves are in TXT file format, as required in current Audacity and compatible down to version 2.4.0).

78 rpm shellacs

pre-RIAA 33⅓ LPs

Individual fine tuning

In some cases it will be not enough to apply the correct EQ to get the desired result. According to the condition of the record and to personal listening preferences you might consider one of the following methods:

  • The 250-or-300-Hz dilemma: To use “European250” or “Blumlein300” EQ seems to be not a question of right or wrong but of personal listening preferences. In general, Continental European authors prefer 250 Hz (derived from the original Western Electric recommendation) for Decca (Brit. and Europ.), Brunswick, Cetra, Columbia (Brit.), EMI-HMV and Parlophone. Englishman Copeland favors 300 Hz (derived from the recording characteristic of the Blumlein cutter) for British EMI, His Master’s Voice and Columbia and also for Odeon. Copeland puts it like this: “[…] but when I’m not sure I use 300 Hz.” [Copeland, Manual, p 129]. Being derived from the previous 250-or-300-Hz curve the same applies to “DECCA78” which was used from 1944 for shellacs with the ffrr system. So you should also feel free to decide the 250-or-300-Hz question according to your own listening preference: 300 Hz will give an extra amplification of bass in play back (ca 1.5 dB at 50 Hz).

  • To remove low frequency noise Robinson (MidiMagic) recommends a low cut filter at 100 Hz with just 6 dB/octave. (Especially for many acoustic recordings which have only noise below 150 Hz or for the “long-playing” shellacs of RCA Victor of 1931/32). This filter will do exactly the same as the “C”-type bass shelf of Columbia LP curve.

  • Vadlyd uses a variable low cut filter for American Victor, early British Decca, EMI, His Master’s Voice and Columbia at frequencies between 40 and 70 Hz. This is very similar to the recommendation of Phonomuseum.org. In Audacity you can experiment with different settings for “Frequency” and “Roll-off” in Effect -> High Pass Filter (a different word for Low Cut Filter) and listen to the result with “Preview”.

  • All bass shelf settings on analog equalizers (R-B-A-C-X) can also be used to remove low frequency noise (especially from acoustics and early shellacs). This is why the extra positions X and A were provided [MidiMagic]

  • A known trick of recording engineers was to increase bass t/o frequency on very long recordings. Thus bass attenuation was increased and bass amplitude and necessary groove width were reduced. So the given duration of the audio could be squeezed into the given space on the disc. If a disc is filled with grooves as can be a higher bass turnover frequency can be necessary to restore the original sound. Example: Colosseum [ES]

  • To improve the weak bass on some 45s (especially on EPs – Extended Play) Esoteric Sound uses a higher turnover frequency for bass in replay than in pre-equalization. For example 700 Hz instead of the “correct” 500 Hz. This will give a smooth, extra bass amplification of roughly 4 dB at 50 Hz.

  • To reduce surface noise of early American Columbia, Victor and RCA-Victor iasa recommends an additional high cut (= low pass) filter set to 5500 or 5200 Hz with 6 dB/octave. This will reduce treble by 3 dB at around 5000 Hz and by 9 dB at 10000 Hz – and hopefully most of the noise.

Remarks for Analog Purists

  • Hiss and high frequency scratch due to old worn records: When digitizing such recordings Audacity’s will do a good job to improve the sound once and for all. Those who prefer entirely analog replay with an adjustable pre-amplifier will have the opportunity to improve the sound every time they replay. They can cut / attenuate the frequency range most affected by the noise. A higher value for roll-off at 10 kHz than the “correct” EQ will usually give a better result than a simple treble filter – but: at the expense of the high frequencies of the audio itself.

  • Dull, lifeless sound: If you improve poor bass on discs of any speed by choosing a higher bass turnover frequency than the “correct” EQ, there will be the welcome side effect of moderately amplifying midrange frequencies. This will bring life to the core octaves of a piece of music by improving instrument and vocal characteristics.

Acoustic recordings and Broadcast Transcription Discs

Acoustic recordings (before 1926) are beyond the scope of this page. In these pioneer years speeds varied from 70 to 90 rpm, groove modulation could be lateral, vertical or diagonal and some records were even cut outward with the audio starting at the center. A special turntable and a range of styli / needles are needed to replay.

All acoustics were recorded without any pre-equalization, simply because a modification of the audio was impossible before electric microphones and amplifiers came into use. Nonetheless there are conflicting opinions as to the result:

According to various authors the acoustical recording process had an "inherent mechanical equalization", which results – within the limited frequency range of approx. 150 to 4000 Hz – in a constant velocity characteristic one would only expect from a magnetic cutter. With a magnetic cartridge this would command to be replayed “flat”. Please note that the acoustical recording characteristic is not equalized at all.

According to Robinson an acoustical recording must have a constant-amplitude characteristic which will be correctly reproduced by playing back with a gramophone needle or a piezoelectric crystal pickup. A magnetic cartridge will – by its constant velocity characteristic – double the amplitude whenever the frequency doubles. To compensate for the magnetic pickup MidiMagic recommends an “800N-16” EQ curve, which comes close to the theoretical characteristic of a constant velocity device. Some more information is here on record labels and on technical background. Please note that the acoustical recording characteristic is not equalized at all.

Kolkowski’s results of a reenactment of an acoustic recording session show that bass needs heavy equalization if the losses in the recording horn (here below 400 Hz) shall be compensated for. Parametric equalization may be used at resonant frequencies. Treble should be amplified (!) to compensate for the high-frequency roll-off of the recorder. Due to the individual properties (defects) of recording horns and recorders there will be no “general characteristic” of acoustics and therefore no general EQ.

MidiMagic gives useful information on vintage labels as Edison, Berliner, Pathé or Zonophone and playback EQ recommendations.

Scientific help regarding valuable historic recordings can be found at IASA (International Association of Sound and Audiovisual Archives) and at ARSC (Association for Recorded Sound Collections).

Broadcast Transcription Discs are not in the focus of this page either. Those were recordable lacquer discs, mostly 16 inch in diameter, played at 33⅓ or 78 rpm. They were professionally used by radio broadcasters. Some more information is in this PDF.

In America many of these discs were recorded under the standard of the National Association of Broadcasters (NAB) of 1942. The very same recording curve had been used by NBC under the name “Orthacoustic” since mid 1930s. This “NAB Transcription (1942)” playback EQ setting can be downloaded here.

The British Broadcasting Corporation (BBC) used a rather exotic curve as a house standard. The version in use after 1949 has been reconstructed from Longford-Smith’s publication of 1952 as an Audacity EQ setting “BBC Transcription (1949)” and can be downloaded here.

78 rpm shellac labels and their EQ

This page is about electrical recordings since 1925 on 78 rpm discs made of shellac! The invention of the Electrical Recording System by Bell Laboratories / Western Electric which was licensed to industry leaders Columbia Records and Victor set some de-facto standards: speed is always 78 rpm, cut is always lateral (same as later mono LPs) and the groove type is always Normal Groove (also named coarse groove). Therefore shellacs are sometimes referred to as N78 (which stands for normal groove discs, played at 78 rpm).

A turntable capable of 78 rpm will be useful. You will need a MONO stylus with 2.5 mil (64 μm), for early electricals possibly one with 3 mil (76 μm) and this Audacity Wiki!

It is assumed that you replay your discs “flat” (without any analog de-equalization) and apply the necessary EQ after digitizing with Audacity . If it is necessary to play the record through a system that applies modern RIAA equalization, select the "RIAA" curve in Audacity's Filter Curve EQ effect and use the Invert button to invert and thus remove the incorrect RIAA equalization before applying the appropriate equalization to the recording.

In case sources did not agree on one EQ curve, their different opinions are listed and you will have to trust your ears.

Table 2: 78 rpm Shellac Labels and Their EQ

Label

Remarks

Curve Name

Code

turnover bass [Hz]

bass shelf

treble roll-off [dB @ 10kHz]

_Electrical 78's (general)

1925-1938

300

0

ES

_Electrical 78's (general)

1932-1938, mid 30s

500-FLAT

500N-0

500

0

ia,ES,JP,RF

_Electrical 78's (general)

1938-1946

300 or 500

0 or -5

ES

_Electrical 78's (general)

1947-1954

300 or 500

-16

ES

Aco

1926 - 1933, British, with M in a circle

BBC 2dB/oct.

PC

Aeolian-Vocalion

1926 - 1933, British, with M in a circle

BBC 2dB/oct.

PC

ARC

American Record Corporation = Cameo + Pathé + Plaza Group; 1929 - 1930

500

0 or -5

PC,JP

ARC

American Record Corporation; 1930 - 1939 (some early also 500-5)

500

-8.5

JP

Argo

American 78

250N-6

250

-6

mm

Ariel

1925 - 1931, British, with Δ after matrix no. or with W in a circle

[W.E.]

250

W.E.mike

PC

Artist

500

-16

ES

Audiophile

1952 - 1955, 78 rpm microgroove (!) records, up to AP-30; may also be replayed with "flat" treble

Audiophile78

300N-8

300

-8

RH,Mc,AT

Autograph

Marsh Laboratories, ca. 1924 - 1926

1000

0

ES,JP

Banner

1926 - 1929, an ARC label from 1929

500

0

JP

Balkan

500

-5

ES

Beltona

1926 - 1933, from cat. 1194 to 1282, with M in a circle

BBC 2dB/oct.

PC

Beltona

1944 - 1955, ffrr, prod. by Decca UK,

Decca 78

300N-5.5

300

-5,7

PC

Bluebird

sublabel of RCA, see: RCA-Victor

Bluebird

1925 - 1931, with VE in an oval or "Orthophonic Recording" or with Δ after matrix no. (recorded in Europe)

[W.E.]

250

W.E.mike

PC

Broadcast (American)

American 78

250N-6

250

-6

mm

Broadcast (American)

1940s

500

-12

JP

Broadcast (British)

1926 - 1933, with M in a circle

BBC 2dB/oct.

PC

Brunswick (American)

1925 - 1930

500-FLAT

500N-0

500

0

ia,JP,RF,PC

Brunswick (American)

1929 - 1935, an ARC label from Dec 1931 to 1940

500

-5

JP

Brunswick (American)

1935 - 1939

500

-8.5

JP

Brunswick (American)

1946 - 1951 or 1954, a Decca (Amer.) label since 1941

630N-?

629

-8 or -12

ES,mm

Brunswick (British)

1925 - 1944, a Decca label since 1932; see: Decca (Brit.)

European 78

250N-0

250

0

ES,GH

Cameo

1926 - 1929, probably W.E.; an ARC label from 1929

[W.E.]

250

0/W.E.

JP

Capitol

earliest 78s

1000

PC

Capitol

1942 - 1953; Capitol founded in 1942; since 1954 => RIAA

Capitol [CAP]

400N-12.7

400

-12.7

ia,ES,mil,JP,Mc

Capitol

1942 - 1951

American 78

250N-8

250

-8

mm

Capitol

to 1954

800

-10

ES

Capitol / Capitol Cetra

1951-1955

Capitol [CAP]

400N-12.7

400

-12.7

mm

Capitol - Telefunken

500-FLAT

500N-0

500

0

ES,mil

Capitol (British)

1944 - 1955, "ffrr", prod. by Decca UK, matrix prefix DCAP

Decca 78

300N-5.5

300

-5,7

PC,JP

Cetra

founded 1930s by RAI, Italy

European 78

250N-0

250

0

GH

Cetra-Soria

founded 1949, Cetra prod. in US

European 78

250N-0

250

0

mm

Chappell

1931 - 1944, British, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Coliseum

1926 - 1933, British, with M in a circle

BBC 2dB/oct.

PC

Columbia (American)

1925 - 1931 (some -1934)

[W.E.]

200 - 250

-5 / W.E.

AT,ES,mil,ia,JP

Columbia (American)

1931 - 1937

American 78

250N-8

250

-8

AT,mm,JP

Columbia (American)

1939 - 1956; "Columbia Rec." a CBS label since 1938; from 1955 change to RIAA

Columbia 78

300N-16

300

-16

ia,GH,ES,mil,mm, JP,Mc,AT

Columbia (British)

1925 - 1931, with W in a circle

[W.E.]

250

W.E.mike

PC

Columbia (British)

1931 - 1953, an EMI UK label from 1931

European 78

250N-0

250

0

ia,GH,ES,JP,RF

Columbia (British)

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Columbia (British)

1932 - 1949, with W in a circle or matrix prefix W (US COL/OKeh reissues)

500-FLAT

500

0, later -12

PC

Columbia (British)

1949 - 7/1953, EMI UK, matrix nos. from CA22600 to CA22610, and at CAX11932

500-FLAT

500N-0

500

0

PC

Concert Hall

500

-5

ES

Coral

1948 - 1954

629

-12

ES

Coral

1948 - 1953, sublabel of Decca US; from 1953 => RIAA

AES

400N-12.3

400

-12.3

JP

Decca (American)

1934 - 1937, (Decca US established in 1934)

American 78

250N-8

250

-8.5

JP

Decca (American)

1937 - 1946 ca

AES

400N-12.3

400

-12.3

ia,JP,RF

Decca (American)

pre 1946, imports from Britain?

Blumlein300

300N-0

300

0

ES

Decca (American)

very few, to try a combination of 500Hz / 6300 Hz

500N-5.5

500

-5,5

mm

Decca (American)

1946 - 1951, if labeled "ffrr"

Decca 78

300N-5.5

300

-5,7

mm

Decca (American)

1946 - 1954 (??? 629 Hz ???)

629

-12

ES

Decca (American)

1951 - 1953, from 1953 => RIAA

AES

400N-12.3

400

-12.3

mm

Decca (British)

1929 - 1944

European 78

250N-0

250

0

ES,mm

Decca (British)

1935 - 1944, matrix up to DR8485-2; test disc: Decca EXP55 or Z718

Blumlein300

300N-0

300

0

PC

Decca (British)

1944 - 1955, ffrr, cat. nos. from F.8440, K.1032, M.569 and X.281 (some exceptions); matrix nos. 8486 to 18000; test disc: Decca K.1802, London T.4996

Decca 78

300N-5.5

300

-5,7

PC,ES,mm,JP

Decca (British)

some 1949-1956

London LP

500C-10.5

500

C

-10,5

mm

Decca (European)

to 1944

European 78

250N-0

250

0

mm

Decca (European)

1944-1950

Decca 78

300N-5.5

300

-5,7

ES,mm

Decca (European)

1950-1954, (Telefunken + Decca UK = TELDEC since 1950)

Telefunken

400N-0

400

0

mm

Decca (European)

some 1954-1962

CCIR 78

350N-10.5

354

-10,5

mm

Deutsche Grammophon

alias "DGG", taken over by Telefunken 1937

300

-5

ES,mil

Deutsche Grammophon

1944 ca. - 1953 ca. (???)

European 78

250N-0

250

0

PC

Dial

78s used same EQ as 33⅓ and 45s

Columbia LP

500C-16

500

C

-16

ES,mil

Domino

1926 - 1929, an ARC label from 1929

500

-5

JP

Dot

to 1958

AES

400N-12.3

400

-12.3

mm

Electrola

800

-10

ES,mil

EMI-HMV (British)

some, re-releases of acoustics mastered 1909-1926

800N-12

800

-12

mm

EMI-HMV (British)

1927 - 1953

European 78

250N-0

250

0

GH,ES,mil,mm

EMI-HMV (British)

1931 - 1944, with □ after matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

EMI-HMV (British)

1931 - 1949, with ◊ after matrix no.

500-FLAT

500

0, later -12

PC

EMI-HMV (British)

1931 - 1953, (test disc HMV DB4037)

European 78

250N-0

250

0

ia,ES,mil,JP,PC

EMI-HMV (British)

11/1943 - 7/1953, matrix nos. from 2EA17501 to 0EA17576

European 78

250N-0

250

0

PC

EMI-HMV (British)

1955 - end, test disc: EMI JGS812, BBC DOM86

CCIR 78

350N-10.5

354

-10,5

PC

Exclusive

1944 - 1949

Decca 78

300N-5.5

300

-5,7

mm

Gramophone Company

1925 - 1931 UK, with Δ after matrix no.

[W.E.]

250

W.E.mike

PC

Gramophone Company

Blumlein300

300N-0

300

0

ES,mil

Harmony

1929 - 1931

250

-5

JP

His Master's Voice (Brit.)

some, re-releases of acoustics mastered 1909-1926

800N-12

800

-12

mm

His Master's Voice (Brit.)

1925 - 1931 British, with Δ after matrix no.

[W.E.]

250

W.E.mike

PC

His Master's Voice (Brit.)

1931 - 1953, prod. by EMI(UK)

European 78

250N-0

250

0

ia,GH,mm,JP,RF

His Master's Voice (Brit.)

1932 - 1949, with ◊ after matrix no.

500-FLAT

500

0, later -12

PC

His Master's Voice (Brit.)

11/1943 - 7/1953, EMI UK, matrix nos. from 2EA17501 to 0EA17576

500-FLAT

500N-0

500

0

PC

Hispanophone

1926 - 1931 , with Δ after matrix no.

[W.E.]

250

W.E.mike

PC

Hit of the Week

1930 - 1932

500

-5 or -8.5

ES,mil,JP

Homochord

1926 - 1928, matrix no. HH, JJ, HR, JR, Ee (made by Gramophone Co.)

[W.E.]

250

W.E.mike

PC

Hugophone

1925 - 1931, with W in a circle

[W.E.]

250

W.E.mike

PC

Hugophone

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Jewel

1926 - 1929, an ARC label from 1929

500-FLAT

500N-0

500

0

JP

Keynote

500-FLAT

500N-0

500

0

ES

Keynote

1940s

500

-12

JP

King

1946 - 1953, since 1953 => RIAA

500

-8.5 or -16

ES,mil,JP

Lincoln

sublabel of Cameo, 1926 - 1929, probably W.E.

[W.E.]

250

-5 / W.E.

JP

Linguaphone

1926 - 1933, with M in a circle

BBC 2dB/oct.

PC

Linguaphone

Blumlein300

300N-0

300

0

ES,mil

L'Oiseau-Lyre

1944 - 1955, ffrr, prod. by Decca UK,

Decca 78

300N-5.5

300

-5,7

PC

London

1948 - 1955, ffrr, prod. by Decca UK,

Decca 78

300N-5.5

300

-5,7

PC,mil,JP

MacGregor

1930 - 1950s, a Hollywood recording studio; produced by Brunswick, ARC, Capitol,...; various EQs (250-5, 250-8, 400-12.7, 500-12)

mm,JP,AT

Majestic

1942 - 1948

500

-16

ES,JP

Marsh Laboratories

(electrical)

1000

0

ES

Melotone

1931 - 1938, a Brunswick budget label; see Brunswick (Amer.)

Mercury

1945 - 1953; approx. to matrix YB9700; since late 1953 => RIAA

AES

400N-12.3

400

-12.3

ia,ES,mm,JP,Mc

MGM (American)

founded 1946; up to E3071

MGM [MGM]

500N-12

500

-12

ia,ES,mil,JP,RF

MGM (British)

1949 - 7/1953, matrix no. 0SM420

500-FLAT

500N-0

500

0

PC

Musicraft

??? RCA Old Ortho.???

700-800

-13.7

ES,mil

Musicraft

500

-8.5 or -12

JP

Nat. Gramophonic Soc.

1926 - 1933, with M in a circle, cat. HHH to TTT and NGS.65 to NGS.102

BBC 2dB/oct.

PC

Nixa

1950 - ?, Britain, shellacs produced by Decca UK

Decca 78

300N-5.5

300

-5.7

ris

Octacros

1931 - ?, Britain, a Synchrophone label

Blumlein300

300N-0

300

0

PC

Odeon

some early electricals

800

0

ES,mil

Odeon

1925 - 1928, with W in a circle (a Lindström label)

[W.E.]

250

W.E.mike

PC

Odeon

1928 - 1936, matrix with ₤ in a circle ( a Lindström label); bass shelf at 100Hz

400

C

0

PC

Odeon

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Odeon

to 1953, (1926 sub. of Brit. Columbia , 1931 sub. of EMI)

Blumlein300

300N-0

300

0

ES,mil

OKeh

1926 - 1935, a Columbia label since 1926

[W.E.]

250

-5 / W.E.

AT,JP,mm

OKeh

1931 - 1935, some; probably American78

American 78

250N-8

250-300

0 or -8.5

ES,mil

OKeh

1940 - 1945 and 1951 - 1955; since 1955 => RIAA

Columbia 78

300N-16

300

-16

AT,JP

Oriole

1926 - 1929, an ARC label from 1926

500

-5

JP

Parlophone (Amer.,Brit.)

1925 - 1931, with W in a circle

[W.E.]

250

-5 / W.E.

PC,JP

Parlophone (British)

1925 - 1953

European 78

250N-0

250

0

GH,ES

Parlophone (British)

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Parlophone (British)

1932 - 1949, with W in a circle or matrix prefix W (US COL/OKeh re-issues for UK)

500-FLAT

500

0, later -12

PC

Parlophone (British)

1949 - 7/1953, EMI UK, matrix nos. from CE14643 to CE14689

500-FLAT

500N-0

500

0

ia,PC,JP,RF

Parlophone-Odeon

1925 - 1928, Odeon in Brit.; with W in a circle

[W.E.]

250

W.E.mike

PC

Parlophone-Odeon

1928/29, Odeon in Brit.; matrix with ₤ in a circle, bass shelf at 100Hz

400

C

0

PC

Pathé (American)

1926 - 1929, probably W.E., some 500-5; an ARC label from 1929

[W.E.]

250

-5 / W.E.

JP

Pathé (French)

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Perfect

1926 - 1929, probably W.E., sublabel of Pathé (Amer.)

[W.E.]

250

-5 / W.E.

JP

Philips

to 1953

Philips

400N-6

400

-6

mm

Polydor

sub-label of Deutsche Grammophon

300

-10

ES,mil

Radiofunken

Telefunken

400N-0

400

0

mil

RCA Victor

12/1931 - 2/1932 "long-playing" shellacs, N-groove, played at 33⅓ rpm

≈Old Ortho.

500N-13.7

500 or up

-13.7

RM,PC

RCA Victor

1931 ca., test disc Victor 84522 without treble pre-emphasis

500-FLAT

500N-0

500-600

0

PC,ES

RCA Victor

1931 - 1938, used high cut at 5500 Hz [R-B]

≈Old Ortho.

500N-13.7

500 or up

-13.7

RM,PC

RCA Victor

1938 - 1947, used High Cut at 8500 Hz, [R-C]

Old Ortho.

500N-13.7

500

-13.7

RM,PC,ia,JP,ES, mil

RCA Victor

1941 - 1947 (some to 1952)

Old RCA

800N-8

800

-8

mm

RCA Victor

1947 - 1951 [R-D]

RCA 45

800N-13.7

800

-13.7

mm

RCA Victor

1947 - Aug 1952 [R-D]

Old Ortho.

500N-13.7

500

-13.7

RM,ia,mm,JP,RF

RCA Victor

since Aug 1952 => "New Orthophonic" = RIAA, from matrix E2RP4094

RIAA

500R-13.7

500

R

-13.7

RM,ES

RCA Victor (British)

1931 - ?, with swastika after matrix no., re-issued by EMI UK

European 78

250N-0

250

0

PC

RCA Victor (British)

1931 - 1944, with □ after matrix no., re-issued by EMI UK, [Bc]

Blumlein300

300N-0

300

0

PC

RCA Victor (European)

1930 - 1950

European 78

250N-0

250

0

ES

Regal (American)

1926 - 1929, an ARC label from 1929

500

-5

JP

Regal (British)

1925 - 1931, with W in a circle

[W.E.]

250

W.E.mike

PC

Regal Zonophone (Brit.)

budget label of EMI/Columbia

European 78

250N-0

250

0

ES,mil

Regal Zonophone (Brit.)

1925 - 1931 UK, with Δ after matrix no. or with W in a circle

[W.E.]

250

W.E.mike

PC

Regal Zonophone (Brit.)

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Regal Zonophone (Brit.)

1932 - 1949, with W in a circle or matrix prefix W (US COL/OKeh reissues for UK)

500-FLAT

500

0, later -12

PC

Regal Zonophone (Brit.)

1949 - 7/1953, matrix no. CAR6800

500-FLAT

500N-0

500

0

JP

Romeo

1926 - 1929, sublabel of Cameo; probably W.E.

[W.E.]

250

0 / W.E.

JP

Scala

1926 - 1933, with M in a circle

BBC 2dB/oct.

PC

Schirmer

1000

-24

mil

Supraphone

Czech, since 1932, a subsid.of Ultraphon

Telefunken

400N-0

400

0

ES,mil

Synchrophone

1931 - ?, Britain

Blumlein300

300N-0

300

0

PC

Technichord

American, all N78 from 1938 [TCH]

Technichord

800N-12

800

-12

ES,mil,mm

Telefunken

1944 - 1955, ffrr, prod. by Decca UK,

Decca 78

300N-5.5

300

-5,7

mm,PC

Telefunken

1951-1953, (Telefunken + Decca UK = TELDEC since 1950)

Telefunken

400N-0

400

0

mm

Tempo (American)

Tempo Record Co. of America, Hollywood, CA; ca 1947 - late 1950s

500

-12

JP

Tempo (American)

400N-6

400

-6

mm

Theme

sublabel of Tempo (Amer.)

500

-12

JP

Theme

all N78

American 78

250N-6

250

-6

mm

Turicaphon

Switzerland, 1930 - , a subsid.of Ultraphon

Telefunken

400N-0

400

0

Ultraphon

Europe 1929-1932, taken over by Telefunken

Telefunken

400N-0

400

0

ES,mil

Unison

1926 - 1933, with M in a circle

BBC 2dB/oct.

PC

Victor

1925 - 1931, Western Electric System

[W.E.]

200 - 300

0 to -7

ia,JP,ES,mil,mm

Victor

Victor was taken over by RCA in 1930; see: RCA-Victor

Victor / Victrola

1925 - 1931, with VE in an oval or "Orthophonic Recording" or with Δ after matrix no. (recorded in Europe)

[W.E.]

250

W.E.mike

PC

Vocalion (American)

a Brunswick label since 1924; see: Brunswick (Amer.)

Vocalion (British)

1926 - 1940; a Brunswick and since 1932 a Decca UK label

European 78

250N-0

250

0

ES,mil

Vocalion (British)

1926 - 1933, to cat. X10029 A.0269 and K05312, with M in a circle

BBC 2dB/oct.

PC

Vocalion (British)

1944 - 1955, "ffrr", prod. by Decca UK, including V1000 series

Decca 78

300N-5.5

300

-5,7

PC

Voice of the Stars

1931 - 1944, with © before matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Zonophone

1925 - 1931 UK, with Δ after matrix no.

[W.E.]

250

W.E.mike

PC

Zonophone

1931 - ?, with swastika after matrix no.

European 78

250N-0

250

0

PC

Zonophone

1931 - 1944, with □ after matrix no., [Bc]

Blumlein300

300N-0

300

0

PC

Remarks
  • [Bc] ... Due to changes in the setup of the Blumlein cutter the characteristic of the recordings could vary between 180 Hz-FLAT and 500 Hz-FLAT, resulting in +/- 4 dB at 50 Hz. Copeland suggests 300 Hz as an average value.

  • [CAP]... used its own “Capitol curve” 400N-12.7. Play back with “AES” 400N-12.3!

  • [MGM] ... used a special “MGM curve” 500N-12. Play back with “RCA Old Orthophonic” 500N-13.7!

  • [R-D] ... Roll-off is frequently listed as between 10 and 12 dB. But this “flattening off” to ca 10 dB at 10 kHz was an intentional high cut which must not be compensated for in playback. Thus a setting of 13.7 dB is correct!

  • [R-C] ... RCA recommends replaying with “Old Ortho.”. High frequencies were cut off more deliberately at 8,500 Hz (with no effect on playback EQ!) than in later years. [cf. Moyer]

  • [R-B] ... From c. 1931 to 1938 high frequencies were even cut off at 5,500 Hz! The bass curve is “subject to some question, however,” since it was extensively modified by electronic filters and mechanical damping. But RCA found 500 Hz to be the best average characteristic and used this in re-recording pre-1938 masters. So in principle: “Old Ortho.” for playback again! [cf. Moyer]

  • [TCH] ... Technichord used its own “Technichord curve” 800N-12. Play back with “RCA 45” 800N-13.7!

  • [W.E.] ... Very early Columbia and Victor recordings (1926) used a bass turnover frequency of 250 or 300 Hz but their treble is described as “flat”. The perceived treble amplification was possibly only the result of resonant peaks of the early Western Electric condenser microphones used in recording. Background information is given in this PDF. An experimental replay EQ curve for this microphone / pre-emphasis combination can be downloaded ‎here.

Early 33⅓ LP labels and their EQ

After the launch of the “long-playing record 33⅓ rpm” by Columbia in 1948 (which used vinyl discs and a narrower groove width – microgroove records or M33) record producers experimented a lot to fully exploit the potential of the new medium. Bass shelving came into use to limit the necessary bass boost in playback and – as a consequence of the extended frequency range – necessary gain reached values as high as +/- 20 dB. So recording characteristics varied considerably!

The “poor sound quality” of some early LPs is nowadays considered to be mostly a result of the wrong EQ in playback.

Standardization was reached with the “New Orthophonic” curve of RCA which was to become the world standard by the name of RIAA. In America most labels switched to RIAA around 1955 – Europe followed by 1962.

How to identify RIAA recordings:

  • “ORTHOphonic” or “New Orthophonic” (after August 1952), “NARTB” or “New NARTB” (after June 1953) or “New AES” (after 1954) indicate RIAA equalization.

  • The following labels should have used only RIAA all the time: Argo, Bethlehem, Classic Editions, Chess, Clef, Composer Recordings, McIntosh, Montilla, New Jazz, Norgram, Prestige, Romany, Roulette, Savoy, Vocalion and Walden [High Fidelity Magazine, MidiMagic].

  • A “HIFi+” sticker on American Columbias or the catalogue number written in an inverted triangle on German records (like Deutsche Grammophon) is a symbol for RIAA.

  • Later recordings on the labels listed below should all be RIAA.

In case that sources did not agree on one EQ curve, their different opinions are listed and you will have to trust your ears.

Table 3: Early 33⅓ LP Labels And Their EQ

Label

Remarks

Curve Name

Code

turnover bass [Hz]

bass shelf

treble roll-off [dB @ 10kHz]

Allegro

1948 - 1956

Columbia LP

500C-16

500

C

-16

ES

Allied

to 1958

NAB or Col.LP

500?-16

500

B/C

-16

JP,Hi,ES,mil,mm

American Recording Society

to matrix E2KP9607, mastered by RCA

Old Ortho. [R-D]

500N-13.7

500

N

13.7

ES,Mc

American Recording Society

to 1958

AES

400N-12.3

400

N

-12.3

Hi,mm,JP

Angel

(2XEA213-392/XAX561-817)(1N,2N)

500-FLAT

500N-0

500

N

0

ES

Angel

to 1952; to 35022

Old Ortho. [R-D]

500N-13.7

500

N

13.7

mil,mm,RF,Mc

Arizona

to Sept(?) 1955

Capitol [CAP]

400N-12.7

400

N

-12,7

Hi,ES,mil,mm,JP

Artist

NAB

500B-16

500

B

-16

GH,mil

Atlantic

to 1953, produced by MGM

NAB

500B-16

500

B

-16

ES,mil,mm,JP,Mc

Audio Fidelity

no. 901-903

NAB

500B-16

500

B

-16

ES,mm,JP,RF

Audiophile

1952 - 1976 (!); regular 33⅓ LPs up to AP-125; may also be replayed with "flat" treble; probably never used RIAA

Audiophile33

600N-10

600

N

-10.3

RH,AT

Bach Guild

sublabel of Vanguard; BG-501 to 529 (1950 to 52)

Columbia LP

500C-16

500

C

-16

GH,ES,Hk,Hi,AT

Banner

to 10002

Columbia LP

500C-16

500

C

-16

ES,mil,mm

to 1952

Columbia LP

500C-16

500

C

-16

ES,mm

Bartók

1952-1953

AES

400N-12.3

400

N

-12.3

mm

Bartók

no. 301-307, 309, 906-920

Bartok

630C-16

629

C

-16

ES,mil,mm,JP,Mc

Bartók

no. 308, 310-11, 901-05 and from 921

RIAA

500R-13.7

500

R

-13,7

Hi

Blue Note

to Sept(?) 1955, 33⅓ and 45s

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP, Hk,Mc

Bluebird

Bluebird Classic (BC), a sublabel of RCA, see: RCA-Victor

Boston

to 1958, up to B202

Columbia LP

500C-16

500

C

-16

Hi,ES,mil,mm,JP, RF

Brunswick

to matrix MG4400; with raised matrix**

Old RCA

800N-8

800

N

-8

ES

Brunswick

1951-1955

AES

400N-12.3

400

N

-12.3

mm

Caedmon (American)

founded 1952, TC1002 - TC1022 (1955)

Bartok

630N-16

629

N

-16

Hi,ES,mil,mm,JP

Caedmon (American)

629

-11 or -12

ES,Mc

Caedmon (British)

early LPs "made in England", from 1953

CCIR 78

350N-10.5

350

N

-10,5

PC

Canyon

to C6160

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP, Hk,Mc

Capitol / Capitol-Cetra

1949 - 1955 (sold to EMI-UK in 1955); 33⅓,

Capitol [CAP]

400N-12.7

400

N

-12,7

Hi,ES,mm,JP,RF, Hk,Mc

Capitol / Capitol-Cetra

1949 - 1954; 45 rpm

NAB

500B-16

500

B

-16

GH,mm

Capitol

to 1954, weak bass on 45 rpm can be improved (+ 4.5 dB) by 800 Hz t/o

500

-12

ES,Mc

Cetra-Soria

Am. releases of Cetra, 1948-1953 (Cetra-Soria sold to Capitol)

Columbia LP

500C-16

500

C

-16

Hi,GH,ES,mm,JP, RF

Colosseum

AES

400N-12.3

400

N

-12.3

ES,mil,RF,Mc

Colosseum

to Jan 1954

NAB

500B-16

500

B

-16

Hi,mm,JP,RF

Colosseum

some long operas

1000

-5

ES

Columbia (American)

1947-1955; to matrix ML4895, XLP3200

Columbia LP

500C-16

500

C

-16

Hi,GH,ES,mil,mm, JP,RF,Hk

Columbia (American)

1948 - 1953; 45 rpm

NAB

500B-16

500

B

-16

ES,mm,Mc

Columbia (American)

45 rpm

AES

400N-12.3

400

N

-12.3

JP

Columbia (American)

1955 - ; after matrix XLP3200 or with "HiFi+" sticker

RIAA

500R-13.7

500

R

-13.7

ES

Columbia (British)

1949 - 7/1953, matrix nos. LPs: from XA561 to XAX817; XRX12; EPs: 7TCA 7, 7TCO 6; SPs: 7XCA185, 7XCO 87

500-FLAT

500N-0

500

N

0

PC,ES

Concert Hall (American)

most! 1948-1954, XTV matrix to 20383 (low take nos) produced by COL

Columbia LP

500C-16

500

C

-16

Hi,ES,mm,JP,RF

Concert Hall

E0 matrix, mastered by RCA, ca. 1950/51

Old RCA

800N-8

800

N

-8

ES

Concert Hall

E1KP/E2KP matrix, mastered by RCA, ca. 1951/53

Old Ortho. [R-D]

500N-13.7

500

N

13.7

ES

Concert Hall

marked AES,

AES

400N-12.3

400

N

-12.3

mil,mm,RF,Mc

Concert Hall

CH matrix?

500

-10

ES

Concert Hall

matrix E2RP from 4095 / E2KP from 9607

RIAA

500R-13.7

500

R

-13,7

ES

Concert Hall (British)

to 1956 (or 1954)

London LP

500C-10.5

500

C

-10.5

Hi,mm,JP

Contemporary

2001-02, 2501-02, 2505, 2507, 3501

AES

400N-12.3

400

N

-12.3

Hi,ES,mm,JP,Mc

Contemporary

2504

NAB

500B-16

500

B

-16

Hi,ES,mm

Contemporary

after matrix AP121

RIAA

500R-13.7

500

R

-13.7

ES

Cook

to 1958(?), regular mono records

Cook

500

N

var. -12 to -15

ES,mm

Cook

Cook Laboratories

NAB

500B-16

500

B

-16

JP

Cook (binaural)

inside band -0 roll-off, outs.-11 dB

500

0 ins./-11 outs.

Hi,ES,mil,mm

Coral

sublabel of Decca (Amer.), est. 1949, up to MG4400, with raised matrix

Old RCA

800N-8

800

N

-8

ES

Coral

AES

400N-12.3

400

N

-12.3

JP,Mc

Coral

to 1958(?)

NAB

500B-16

500

B

-16

Hi,mm,JP

Decca (American)

up to MG4400, with raised matrix

Old RCA

800N-8

800

N

-8

ES

Decca (American)

1949-1951

London LP

500C-10.5

500

C

-10.5

mm

Decca (American)

1953, 33⅓ and 45 rpm

AES

400N-12.3

400

N

-12.3

mm,JP,RF

Decca (American)

1953 - Nov 1955, 33⅓ and 45 rpm

NAB

500B-16

500

B

-16

Hi,mm,JP,RF

Decca (British)

1950-1956

London LP

500C-10.5

500

C

-10.5

mm

Decca (British)

ffrr (from ARL1186-1B)***

???London

500

-10

ES

Decca (British)

ffrr (after 6/50)***

500-FLAT

500N-0

500

N

0

ES

Decca (British)

ffrr (from ARL2530-2A)

RIAA

500R-13.7

500

R

-13.7

ES

Decca (European)

1949 - 1954, (Telefunken + Decca UK = TELDEC since 1950)

Telefunken

400N-0

400

N

0

mm

Decca (European)

some 1954-1962

CCIR 78

350N-10.5

350

N

-10.5

mm

Decca (European)

most from 1954

RIAA

500R-13.7

500

R

-13.7

mm

Decca ffrr

1951 [Disputed!][1]

300

-14

JP,RF

Deutsche Grammophon

alias "DGG"

LP

-10

ES

Deutsche Grammophon

1952 - 1955, early LPs, cat. no in a rectangle, bass shelf 50 Hz

IEC N78

350A-10.5

350

A

-10.5

PC,GH,RB

Deutsche Grammophon

cat. no. in an inverted triangle (RIAA symbol)

RIAA

500R-13.7

500

R

-13.7

PC

Deutsche Grammophon

1957, test disc DG 99105, possibly the only disc to DIN 45533

TELDEC

500R-11

500

R

-11

PC

Dial

1948 - 1954, 33⅓ and 45 rpm, bass of EP 45s can be improved by 700Hz t/o

Columbia LP

500C-16

500

C

-16

ES,mil,mm,JP

Dot

to 1958, 33⅓ and 45 rpm

AES

400N-12.3

400

N

-12.3

mm

Ducretet Thomson

10/1954 - 1958, British releases issued by London/Decca UK

London LP

500C-10.5

500

C

-10.5

RF

Elektra

EKL 2-15, 18-20, 24-26 (rel. 1952-55)

Bartok

630N-16

629

N

-16

Hi,ES,mm,JP,Mc

Elektra

EKL 17, 22 (released 1954)

AES

400N-12.3

400

N

-12.3

Hi,ES,mm,JP

Elektra

EKL 16, 21, 23 (rel. 1955) and from 27 up

RIAA

500R-13.7

500

R

-13.7

Hi,ES,mm

EMI-Angel

to 1952, Deutsche Grammophon releases in US

Old Ortho. [R-D]

500N-13.7

500

N

13.7

mm

EMI-HMV

1949 - 1953; matrix 2XEA213-392/XAX561-817 (1N,2N) 33⅓ and 45 rpm

500-FLAT

500N-0

500

N

0

ES

EMI-HMV

1951 - 1954

NAB

500B-16

500

B

-16

mm

EMI-HMV

1954 - 1958?

Columbia LP

500C-16

500

C

-16

mm,JP

EMI-HMV

since July 1953

RIAA

500R-13.7

500

R

-13.7

ES,PC

EMS

1951 - 1956

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP, RF,Hk,Mc

Epic

1948 - 1954, a Columbia sublabel

Columbia LP

500C-16

500

C

-16

ES,mil,mm,JP,RF

Esoteric

ES 500,517 and EST 5,6

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP

Esoteric

to matrix E2KP 9607, mastered by RCA; from ES 533 => RIAA

Old Ortho. [R-D]

500N-13.7

500

N

13.7

ES,Mc

Festival

to 1955

Columbia LP

500C-16

500

C

-16

ES,mil,mm

1948 - 1955; all

Columbia LP

500C-16

500

C

-16

Hi,ES,mm,JP,RF

Fraternity Records

up to F-1013

500-FLAT

500N-0

500

N

0

ES

Good-Time Jazz

1, 5-8

NAB

500B-16

500

B

-16

Hi,ES,mm,JP

Good-Time Jazz

3, 9-19

AES

400N-12.3

400

N

-12.3

Hi,ES,mm,JP,Mc

Good-Time Jazz

2, 4, 20 and up; since Oct 1955 => RIAA

RIAA

500R-13.7

500

R

-13.7

Hi,mm

Handel Society

sublabel of Concert Hall, mostly produced by COL, 1951-1954; others see Concert Hall

Columbia LP

500C-16

500

C

-16

ES,mil,mm

Haydn Society

sublabel of Urania; to matrix XTV20383, mastered by COL; to cat. HS-3062, HSL-84; 1949 to 1954

Columbia LP

500C-16

500

C

-16

Hi,ES,mil,mm,JP, Hk,AT

His Master's Voice (Amer.)

sublabel of RCA; to 1952; since Aug 1952 => "New Ortho." = RIAA

Old Ortho. [R-D]

500N-13.7

500

N

13.7

ES,GH,RM

His Master's Voice (British)

1949 - 7/1953, EMI-UK, matrix nos. LPs: 2XEA213 - 392 and 0XAV145; EPs: 7TEA 19, 7TAV 28; SPs: 7XBA14 - 21 and 7XCS 23, 7XLA 2, 7XRA 30, 7XSB 6, 7XVH 70, 7XEA688, 7XAV227

500-FLAT

500N-0

500

N

0

PC,ES

His Master's Voice (British)

Columbia LP

500C-16

500

C

-16

GH,JP,RF

Kapp

no. 100-103, 1000-1001

Kapp

800N-16

800

N

-16

Hi,ES,mil,mm,JP

Kendall

to 1958(?)

NAB

500B-16

500

B

-16

Hi,ES,mil,mm,JP

L'Oiseau-Lyre

to 1954, to matrix OL50018, prod. by Decca

London LP

500C-10.5

500

C

-10.5

Hi,ES,mil,mm,JP

London

first few

Columbia LP

500C-16

500

C

-16

mm

London

ffrr; after 6/1950***; to matrix ARL1186-1B

500-FLAT

500N-0

500

N

0

ES

London

ffrr; to LL-846; to matrix ARL2530-2A

London LP

500C-10.5

500

C

-10.5

Hi,mil,mm,ES

1948 - 1951, XTV matrix, mastered by COL

Columbia LP

500C-16

500

C

-16

mil,mm,JP,RF,ES

Lyrichord

1951 - 1957(?)

NAB

500B-16

500

B

-16

Hi,mm

Lyrichord

1950 - 1952, mastered by RCA

Old Ortho. [R-D]

500N-13.7

500

N

13.7

PC

Lyrichord

400

-16

mil,JP,RF

Lyrichord

before 1953, (E0-E3 matrix)

???AES

400

-12

ES

Lyrichord

if labeled "629"

Bartok

630C-16

629

C

-16

ES,mil,JP,Mc

Mercury

1948 - 1952, marked "2000Hz/3dB p.octave", MG10000 series

500

-7 (3 dB/oct.)

PC,ES

Mercury

1953 - Oct 1954, 33⅓ and 45s, to matrix MG50026, 7000

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP, PC,Hk,Mc

MGM

to 1952

NAB

500B-16

500

B

-16

GH,mm

MGM

to 1953; to matrix M-G-M E3071; 33⅓ and 45 rpm; bass of 45s can be improved by 700 Hz

MGM [MGM]

500N-12

500

N

-12

ES,mm,JP,Hk,AT, Mc

MGM (British)

1949 - 7/1953, matrix nos. SPs: 7XSM203

500-FLAT

500N-0

500

N

0

PC

Music Treasures

all

Columbia LP

500C-16

500

C

-16

mm

New Records

to 1954

Columbia LP

500C-16

500

C

-16

ES,mil,mm

New Records

mastered by RCA

Old Ortho. [R-D]

500N-13.7

500

N

13.7

ES

Nixa (British)

1950 (founded) to 1955, US matrixes from Westminster

Columbia LP

500C-16

500

C

-16

mm,PC

Nixa (British)

to 1955, if labeled AES

AES

400N-12.3

400

N

-12.3

mm

Nixa (British)

to 1955, if labeled NAB

NAB

500B-16

500

B

-16

mm

Nixa (British)

US matrixes from Polymusic or Urania; mastered by RCA Victor

Old Ortho. [R-D]

500N-13.7

500

N

13.7

PC

Nixa (British)

US matrixes from Lyrichord; see: Lyrichord

PC

Nocturne

LP1-LP3 ,LP5; XP1-XP10

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP

Oceanic

to 1958; to matrix XTV20383, low take nos.

Columbia LP

500C-16

500

C

-16

Hi,ES,mil,mm,JP, Hk

Odeon

300

-10

ES

Overtone

nos. 1-5 produced by COL; from no. 6 => RIAA

Columbia LP

500C-16

500

C

-16

ES,TP,AT

Oxford

to 1958?

Columbia LP

500C-16

500

C

-16

Hi,ES,mil,mm,JP

Pacific Jazz

to 1953

Pacific Jazz

500C-12

500

C

-12

mm

Pacific Jazz

PJLP 1-13; 10" LPs issued in 1953/54

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP

Parlophone

1947-1954

300

-10

ES

Parlophone

1949 - 7/1953, EMI UK, matrix nos. LPs: XEX 60; SPs: 7XCE135; (EPs were probably all RIAA)

500-FLAT

500N-0

500

N

0

PC,ES

Period

1949-1953; up to 576

NAB

500B-16

500

B

-16

ES,mil,mm,Mc

Philharmonia

to 1958?

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP, Hk,Mc

Philips

to 1953, 33⅓ and 45s

Philips

400N-6

400

N

-6

mm

Philips (British)

1953 - ?, LPs with re-issues of 78s masters

CCIR 78

350N-10.5

350

N

-10.5

PC,RB

Polydor

sub-label of Deutsche Grammophon

300

-10

ES,mil

Polymusic

to 1958 (regular mono records)

NAB

500B-16

500

B

-16

ES,mil,mm,JP,RF

Polymusic (binaural)

inside band -0 roll-off, outs.-11 dB (Cook system)

500

0 ins./-11 outs.

Hi,ES,mil,mm

Rachmaninoff Society

to 1958?

Columbia LP

500C-16

500

C

-16

ES,mil,mm

RCA Victor

1949 - 1950, some 33⅓ and 45s; matrix from D9 to E0LRC3980

Old RCA

800N-8

800

N

-8 or -10

ES,mm,Mc

RCA Victor

1949 - 8/1952, first 45 rpm discs (also some 33⅓)

RCA 45 [R-D]

800N-13.7

800

N

-13.7

RM,mm,PC

RCA Victor

1950 - 8/1952, 33⅓ only; matrix from E0LRC3981

Old Ortho. [R-D]

500N-13.7

500

N

13.7

RM,ES,mm,JP,PC, Hk

RCA Victor

since Aug. 1952: "New Orthophonic"; all LM,WDM,DM cat. from 1701; LCT,WCT from 1112; all LHMV,WHMV,LBC,WBC and Extended Play 45s; (from E2RP4094)

RIAA

500R-13.7

500

R

-13.7

RM,Hi,GH,ES,PC

Remington

to 1958(?); to matrix 199-135

NAB

500B-16

500

B

-16

Hi,ES,mm,JP,Mc

Renaissance

1949 - 1952

Columbia LP

500C-16

500

C

-16

mm

Renaissance

1952 - 1954

Pacific Jazz

500C-12

500

C

-12

ES,mil,mm,Mc

Riverside

to Sept (?) 1955

AES

400N-12.3

400

N

-12.3

Hi,ES,mil,mm,JP

Stradivari

to 1958

Columbia LP

500C-16

500

C

-16

ES,mil,mm

Telefunken

1951 - 1953, (Telefunken + Decca UK = TELDEC since 1950)

Telefunken

400N-0

400

N

0

mil,mm

Telefunken

1954 - 1962

CCIR 78

350N-10.5

350

N

-10.5

mm,RB

Tempo

1948 - 1953

Columbia LP

500C-16

500

C

-16

mm

Tempo

1954 - 1958(?)

NAB

500B-16

500

B

-16

Hi,GH,ES,mm,JP

Transradio

to 1958(?)

Columbia LP

500C-16

500

C

-16

Hi,ES,mm,JP

Urania

most; to matrix XTV20383 (low take nos), mastered by COL; 1949 to 1954; since 1953 change to RIAA

Columbia LP

500C-16

500

C

-16

Hi,mil,mm,ES,Hk, AT

Urania

Cat. nos. URLP 224, 603, 7059, 7063, 7065, 7066, 7069; ca 1952/53

AES

400N-12.3

400

N

-12.3

Hi,mm,JP,Mc,AT

Urania

to matrix E2KP9243, mastered by RCA; 1950 to 1953

Old Ortho. [R-D]

500N-13.7

500

N

13.7

PC,ES,AT

Vanguard

VRS 411-42, 6000-18, up to XTV20386; VRS 7001-11, 8001-04; since 1954 RIAA

Columbia LP

500C-16

500

C

-16

Hi,ES,JP,GH,Hk AT

Vox

1948 - 1954; up to matrix XTV20386, PL8400 or labeled "Lp"; mastered by COL

Columbia LP

500C-16

500

C

-16

GH,mil,mm,JP,ES, PC,Hk

Vox

labeled AES

AES

400N-12.3

400

N

-12.3

mm

Vox

1951 - Oct 1954

NAB

500B-16

500

B

-16

Hi,mil,mm,JP,RF

Westminster

1948 - Oct 1955, to matrix XTV20383 low take nos.; mastered by Columbia

Columbia LP

500C-16

500

C

-16

Hi,ES,mil,mm,JP, PC

Westminster

EO matrix

Old RCA

800N-8

800

N

-8

ES

Westminster

to matrix E2KP9607, mastered by RCA

Old Ortho. [R-D]

500N-13.7

500

N

13.7

ES

Westminster

labeled AES

AES

400N-12.3

400

N

-12.3

Hi,mil,mm,JP,RF

Westminster

labeled NARTB

NAB

500B-16

500

B

-16

GH,JP

Remarks
  • [1]... This EQ can be traced back to Langford-Smith (1952), who vaguely describes a “London LP curve (Jan. 1951)”. Powell reads this as 300Hz (wrong!) and -14 dB (correct!). Copeland judges evidence “to be very defective.” No evidence of usage.

  • [CAP]... used its own “Capitol curve” 400N-12.7. Play back with “AES” 400N-12.3!

  • [MGM] ... used a special “MGM curve” 500N-12. Play back with “RCA Old Orthophonic” 500N-12.3!

  • [R-D] ... Roll-off is frequently listed as between 10 and 12 dB. But this “flattening off” to ca 10 dB at 10 kHz was an intentional high cut which must not be compensated for in playback. Thus a setting of 13.7 dB is correct!

  • [R-C] ... RCA recommends replaying with “Old Ortho.”. High frequencies were cut off more deliberately at 8,500 Hz (with no effect on playback EQ!) than in later years. [cf. Moyer]

  • [R-B] ... From c. 1931 to 1938 high frequencies were even cut off at 5,500 Hz! The bass curve is “subject to some question, however,” since it was extensively modified by electronic filters and mechanical damping. But RCA found 500 Hz to be the best average characteristic and used this in re-recording pre-1938 masters. So in principle: “Old Ortho.” for playback again! [cf. Moyer]

Sources of tables 2 and 3:
  • AT ... AudacityTeam own research

  • ES ... Esoteric Sound and the updated EQ list from the manual of their re-equalizer pre-amp in which they also have very useful tips how to identify LPs by their matrix number (British London / Decca, American Decca, American Columbia, RCA Victor). Please mind that they quote settings of their device which have to be translated back into parameters of EQ curves.

  • GH ... Graumann, Heinz; Schallplatten-Schneidkennlinien und ihre Entzerrung, in: FUNKSCHAU 1958, Heft 15, pp 359 ff

  • Hi ... High Fidelity Magazine, October 1955 with revised “Dialing Your Disks” table.

  • Hk ... Heathkit; Pre-amplifier WA-P2 manual; Heath Comp., Benton Harbor, Michigan; 1954

  • ia ... iasa – International Association of Sound and Audiovisual Archives: replay EQ

  • JP ... James R. Powell Jr., “Audiophile’s Guide to Phonorecord Playback Equalizer Settings”, in: ARSC Journal 20-1, Spring 1989, pp 14-23

  • Mc ... McIntosh Audio Compensator C-8 manual (1956). Please note that McIntosh lists all labels using "Columbia LP" curve with 750 Hz in error.

  • mil ... Millennia Music and Media Systems manufacturer of LOCi pre-ampand other high end professional audio recording products. Their EQ chart was initially part of the manual of the LPE-2 pre-amp. A revised version was released in 2010 as “MM Legacy Recordings“ chart.

  • mm ... MidiMagic is probably the most comprehensive and reliable websource. Data were researched in the 1970s and are based on publications of the 1950s.

  • PC ...Peter Copeland, Manual of Analogue Sound Restoration Techniques, The British Library, 2014

  • RB ... Richard Brice in PspatialAudio

  • RF ... Russell Fisher / W.A.M.S.

  • RM ... Robert C. Moyer, Evolution of a Recording Curve; in: Audio Engineering, vol.37, no.7, July 1953; pp 19-22, 53-54. (about "New Orthophonic" and previous RCA curves)

  • TP ... Tom Packard of Packburn Electronics, Inc. Personal correspondence re Overtone.

  • Discographical information about catalogue numbers, matrix numbers and release dates is based on Both Sides Now, The Online Discographical Project, 45worlds (who also show 78 rpm and LPs), Decca Classical discography by Philip Stuart (July 2009 edition], Record Information Services (post-war UK labels), Yale University, Music Cataloging, Grammophon-Platten.de (German/European labels) and Discogs (database and trading platform) as well as some discographies specialized on specific labels.

  • James R. Powell, Jr. and Randall G. Stehle, "Playback Equalizer Settings for 78 RPM Recordings", Third Edition, Gramophone Adventures, Portage, MI, 1993, 2002, 2007. A compilation of Powell’s subjective recommendations of Owl 1 settings for approx. 1800 discs / 400 labels (mostly American and Jazz). Reprint of 3rd edition available at Nauck’s.

  • Fritz Langford-Smith, Radiotron Designer's Handbook, Wireless Press, Sydney, Fourth edition, 1952.

  • James Moir, High Quality Sound Reproduction, Chapman & Hall Ltd., London, 1958

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