View source for 78rpm playback curves

{{DISPLAYTITLE:Playback equalization for 78 rpm shellacs and early 33⅓ LPs}}
{{Introrel|'''This page serves as a library of additional EQ curves for old disc recordings''' that can be used in the [http://manual.audacityteam.org/help/manual/man/equalization.html Equalization] effect in [http://audacityteam.org/download current Audacity].|While this page deals mainly with 78rpm playback equalization curves, some detail on early (pre-1955) LP curves is also included.|[http://manual.audacityteam.org/man/recording_78_rpm_records.html Audacity Manual: Recording 78 rpm records] 
* [http://manual.audacityteam.org/man/sample_workflow_for_lp_digitization.html Audacity Manual: Sample workflow for LP digitization] 
* [[EQCurvesDownload|All additional EQ Curves for Audacity]]}}

<span title="Ultraphon promotion disc of 1929 - play back with &quot;Telefunken&quot; EQ">[[Image:Ultraphon.JPG‎|right|link=|400px|]]</span>
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.


__TOC__


== Usage == 
The most relevant EQ curves are presented as [[#table_1|Table 1]]:
*You can download some of them from the [[#EQ Curves Library|EQ Curves Library]] section and import them into Audacity using {{menu|Effect > Equalization}}
*You can generate any curve yourself with the [[#78 rpm EQ Curve Generator|78 rpm EQ Curve Generator]] plugin
*You can set the sliders of any digital or analog graphic equalizer manually
*You can determine appropriate settings for any adjustable analog pre-amplifier.

Which EQ curve will be needed for a specific record label is answered:
*for 78 rpm shellacs in [[#table_2|Table 2]]
*for early LPs in [[#table_3|Table 3]]

==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 Record 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 78rpm 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 Rolloff' 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 Rolloff of -13.7dB.  These two curves, when combined, give the characteristic shown in Figure 3.


[[Image:EQ_Bass_Boost_curve.jpg|600px|Bass Boost curve]] 

Figure 1. Bass Boost curve:  3dB at 500 Hz


[[Image:EQ_Treble_cut_curve.jpg|600px|Treble Cut curve]]

Figure 2. Treble Cut curve:  -13.7 dB at 10 kHz


[[Image:EQ_Combined_Bass_boost_and_Treble_cut_curve.jpg|600px|Combined Bass Boost and Treble Cut curve]]

Figure 3. Combined Bass Boost and Treble Cut curve


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.


[[Image:EQ_Bass_boost_Treble_cut_and_LF_shelving_curve.jpg|600px|Combined Bass Boost, Treble Cut and 50 Hz LF Shelving curve]]

Figure 4. Combined Bass Boost, Treble Cut and 50 Hz LF Shelving curve



Acoustically recorded (pre-electric) 78rpm records have a 'flat' EQ curve, i.e. with no bass boost or treble cut and, in some early electric EQ curves, while there is a bass boost curve, the 10 kHz Gain Rolloff is zero, i.e. there is no treble cut.

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 +/- 0.5%.

==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 it 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 the lists provided by the manufacturers of equalizer preamps 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.) 


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 rolloff 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 rolloff 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 preamps.

(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.


<div id="table_1"></div>
'''''Table 1: Playback Equalization Curves'''''

{| class="wikitable"
! style="vertical-align:top;"| Region !! style="vertical-align:top;"|Timeperiod !! '''Curve Name''', alias names !! colspan="3" style="vertical-align:top;"| Time constants  !! colspan="3" | Turnover frequencies  !! Bass shelf !! Bass boost !! Treble cut !!  style="vertical-align:top;"| '''Code'''
|-
|  ||  ||  || τ<sub>1</sub> [μs] || τ<sub>2</sub> [μs] || τ<sub>3</sub> [μs] || f<sub>1</sub> [Hz] || f<sub>2</sub> [Hz] || f<sub>3</sub> [Hz] ||style="vertical-align:bottom"| [dB] || @ 50Hz <br> [dB] || @10kHz <br> [dB] || 
|-
|  ||  || '''''Normal Groove, 78 rpm''''' ||  ||  ||  ||  ||  ||  ||  ||  ||  || 
|-
| Eur., Brit. || 1926 - 1946 || '''"European 78"''', Old Europ.,250,EMI 78 ||  || 636 ||  ||  || 250 ||  ||  || + 14,4 || 0 (flat) || 250N-0
|-
| Eur., Brit. || 1927 - 1946 || '''"Blumlein 300"''' ||  || 531 ||  ||  || 300 ||  ||  || + 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
|- style="border-top:solid thick lightgrey"
| Eur., Brit. || 1944 - 1956 || '''"DECCA 78"''', FFRR 78, London ffrr 78 ||  || 531 || 25 ||  || 300 || 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
|- style="border-top:solid thick lightgrey"

|  ||  || '''''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
|- style="border-top:solid thick lightgrey"

|style="white-space: nowrap;" | Amer.(RCA) || 1949 - 8/1952 || '''"RCA 45"''' (for 45 rpm) ||  || 200 || 63,7 ||  || 796 || 2500 ||  || + 22,6 || - 13,8 || 800N-12.3
|-
| Amer.(RCA) || 1950 - 8/1952 || '''"RCA Old Orthophonic"''' (for 33⅓ LPs) ||  || 318 || 63,7 ||  || 500 || 2500 ||  || + 19,7 || - 12,6 || 500N-12.3
|-
| 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) ||style="white-space: nowrap;" | ca.1956 - pres. ||  = '''"RIAA"''' (US-standard since 1955) ||  ||  ||  ||  ||  ||  ||  ||  ||  || 
|-
| Europe || ca.1962 - pres. ||  = IEC No.98 (1955) = B.S.1928 (1955) ||  ||  ||  ||  ||  ||  ||  ||  ||  || 
|- style="border-top:solid thick lightgrey"

| 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
|}



:::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/Decca releases in US, mostly M33
:::[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

===78 rpm EQ Curve Generator===

EQ Curves for Audacity can be generated from these Frequency and Rolloff values using the '''experimental''' Nyquist plug-in "78 RPM EQ Curve Generator". This plug-in is obtainable from the top of this [http://forum.audacityteam.org/viewtopic.php?f=28&t=33824 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. 

<ol>
<li> Extract 78EQCurveGen.ny from the zip file downloaded from the above Forum topic.
<li> 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 [[Download Nyquist Plugins#install|here]]. 
<li> Click {{menu|Generate > 78 RPM EQ Curve}}. You can find help inside the plug-in by choosing one of the Help options in "Select Function or Help".
<li> Choose the curve you want from one of the lists. 
<li> Enter the values for your chosen curve for 
<ul><li> "Bass Turnover Frequency (Hz)" 
<li> "10 kHz Gain Rolloff (dB)"
<li> "LF Shelving Frequency (Hz)" (if a value is given)</ul>
in the equivalent boxes in the plug-in dialog.
<li>Click "OK" in the plug-in to save the .xml file to your chosen location. 
<li>Select some audio and choose {{menu|Effect > Equalization}}.
<li> Choose "Save/Manage Curves...".
<li> Choose "Import...", navigate to the location where you saved the .xml file from 78EQCurveGen.ny, then "Open".
<li> Click "OK". </ol>    


=== EQ Curves Library ===
Here you can find some useful EQ curves for download to Audacity for use in {{menu|Effect > Equalization}}. How to get an EQ curve from this Wiki and add it to your Audacity’s Equalization effect is explained  [http://wiki.audacityteam.org/wiki/EQCurvesDownload#Adding_the_Curves_to_current_Audacity here].

*[[Media:EQ_toolbox_78rpm.xml|EQ toolbox for 78 rpm shellacs]] contains the following nine EQ curves which can be downloaded individually as well.<p>
**[[Media:500-FLAT_2.1.2.XML‎|500-FLAT 500N-0]]: used by British Columbia, EMI, His Master’s Voice, MGM and Parlophone between 1931 and 1953.  Later releases have modified treble.</p><p>
**[[Media:American_78_2_1_2.XML|‎American 78 – 250N-6/250N-8]]:  Common setting for many American shellacs.  This curve here is a compromise between both varieties with -7 dB rolloff.</p><p>
**[[Media:BBC_Transcription_(1949)_2.1.2.XML‎|BBC 2dB/octave]]: used by smaller British labels (Aco, Broadcast, Linguaphone, Vocalion, …) from 1926 to 1933, which had their recordings mastered by BBC with the Marconi system.</p><p>
**[[Media:Blumlein300_2_1_2.XML|Blumlein300 - 300N-0]]:   A British traditional for Gramophone Company, Decca, Columbia and EMI (1930s – 1944).</p><p>
**[[Media:Columbia_78_2_1_2.XML|‎Columbia 78 – 300N-16]] is the right one for American CBS-Columbia shellacs (1938 - 1948).</p><p>
**[[Media:DECCA_78_2.1.2.XML|Decca 78 – 300N-5.5]]: For Decca and London shellacs featuring the ffrr (full frequency range recording) system.  Here in the version of Copeland/The British Library Sound Archive.</p><p>
**[[Media:European_78_2_1_2.XML‎|European 78 - 250N-0]] is a common setting for European shellacs (1926 – ca. 1944), especially for Columbia and His Master’s Voice produced by EMI (UK), Cetra and Cetra-Soria.</p><p>
**[[Media:Telefunken_2.1.2.XML‎|Telefunken 400N-0]]: used by European Ultraphon, Supraphon and Turicaphon from 1929. Also used by Telefunken – after the takeover of Ultraphon – until mid 1950s.</p><p>
**[[Media:Western_Electric_2.1.2.XML‎|Western Electric]]:  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. The above download is an experimental replay EQ curve for this microphone / pre-emphasis combination. Additional background information is given in [http://audacity.lifey.at/Early%20Western%20Electric%20Characteristic.pdf this PDF].</p>
*[[Media:EQ_toolbox_33_LP.xml‎|EQ toolbox for pre-RIAA 33⅓ LPs]] contains the following six EQ curves which can be downloaded individually as well.<p>
**[[Media:AES_(1951)_2.1.2.XML|‎AES – 400N-12]]: Intended by AES (Audio Engineering Society) as a replay standard for many American shellacs of the 1930s and 1940s.  Also used by many record producers as a recording curve for N78 and M33 between 1951 and 1958.  Also to replay Capitol and Capitol-Cetra recordings with “Capitol curve” 400N-12.7 (1951 – 1955). </p><p>
**[[Media:Columbia_LP_2.1.2.XML‎|Columbia LP – 500C-16]]:  For Columbia and many other labels, mostly 33⅓ LPs (M33).</p><p>
**[[Media:London_LP_2.1.2.XML‎|London LP – 500C-10.5]]:  Used for British Decca and for London / Decca releases in the US featuring the ffrr (full frequency range recording) system.  Mostly 33⅓ LPs (1949 – 1956). Here is the most likely of some slightly different versions which have been published.</p><p>
**[[Media:NAB_(1949)_2.1.2.XML‎|NAB – 500B-16]]:  A widely adopted standard of NAB / NARTB (National Association of Radio and Television Broadcasters) requiring ca. 6 dB more bass boost than Columbia LP.</p><p>
**[[Media:RCA_45_2.1.2.XML‎|RCA 45 – 800N-12.3]]:  RCA’s curve for their 45 rpm discs (1949 – August 1952).  Possibly identical with Technichord’s “Technichord curve” 800N-12 already used since 1938 for their 78s;  if not, the difference will be < 0.3 dB.</p><p>
**RCA New Orthophonic – 500R-13.7, identical with RIAA:  not in this library because it is already one of the standard curves of Audacity’s Equalization tool.</p><p>
**[[Media:RCA_Old_Orthophonic_2.1.2.XML‎|RCA Old Orthophonic – 500N-12.3]]:  RCA’s curve for 33⅓ LPs (1950 – August 1952) and for LPs mastered by RCA for other labels.  Possibly identical with “MGM curve” 500N-12 used by MGM and Audiophile; if not, the difference will be < 0.3 dB.</p>

All these curves are suited for Audacity 2.1.2.

=== 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:

*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 “Rolloff” in {{menu|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]

*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.
{{note|
*The primary thing YOU can do to improve this page is to share your knowledge about EQ curves and their usage with us.  If you have reliable information which record label used which recording curve, please do let us know!

*Please let us have YOUR feedback on this page!  What did work well – and what didn’t?  What was easy to adopt – and what was confusing?

*To give feedback on this page please [http://www.audacityteam.org/contact/#feedback email us]. If you already have an account on this Wiki, please post your comments directly on this article's [http://wiki.audacityteam.org/wiki/Talk:78rpm_playback_curves Talk Page].}}

==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 (“flat”), simply because a modulation of the signal was impossible before electric microphones and amplifiers came into use.  So the signal on the disc has a clean constant-amplitude characteristic.  This is fine as long as you play back with a gramophone needle or a piezoelectric crystal pickup.  But you will probably use a magnetic cartridge which – by its constant velocity characteristic – will double the amplitude whenever the frequency doubles.  To compensate for this Robinson (MidiMagic) recommends a “800N-16” EQ curve, which comes close to the theoretical characteristic of a constant velocity device – a straight line from +20 dB at 100 Hz to -20 dB at 10,000 Hz with constant slope of 6 dB/octave.  This is a very simple curve to draw in Audacity’s Equalization! Some more information is in [http://audacity.lifey.at/acoustics%202016%2005%2019.pdf this PDF].
{{note|[http://midimagic.sgc-hosting.com/mixphono.htm MidiMagic] gives useful information on vintage labels as Edison, Berliner, Pathé or Zonophone and playback EQ recommendations.<p>Scientific help regarding valuable historic recordings can be found at [http://www.iasa-web.org/tc04/mechanical-carriers-replay-equalisation IASA] (International Association of Sound and Audiovisual Archives) and at [http://www.arsc-audio.org/index.php ARSC] (Association for Recorded Sound Collections).</p>}}
'''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 [http://audacity.lifey.at/transcr%202016%2005%2019.pdf 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 [[Media:NAB_Transcription_(1942)_2_1_2.xml|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 [[Media:BBC_Transcription_(1949)_2.1.2.XML‎|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 78.26 rpm,  cut is always lateral (same as modern 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 {{menu|Effect > Equalization}}. If it is necessary to play the record through a system that applies modern RIAA equalization, select the "RIAA" curve in Audacity's Equalization effect and use the {{button|Invert}} button to invert and thus remove the incorrect RIAA equalization before applying the appropriate equalization to the recording. 

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


<div id="table_2"></div> 
'''''Table 2: 78 rpm Shellac Labels and Their EQ'''''

{| class="wikitable" style="background:#FFFAF2; color:#4C2D00;"
!  Label !!  Remarks !! style="white-space: nowrap;" |Curve Name !! Code !! turnover <br> bass [Hz] !! bass <br> shelf !!style="white-space: nowrap;" | treble rolloff <br> [dB @ 10kHz] !! Source
|-
| style="white-space: nowrap;" | _Electrical 78's (general)  || 1925-1938 ||  ||  || 300 ||  || 0 || ES
|-
| _Electrical 78's (general) || 1932-1938,  mid 30s || 500-FLAT || 500N-0 || 500 || N || 0 || ia,ES,JP,RF
|-
| _Electrical 78's (general) || 1938-1946 ||  ||  || style="white-space: nowrap;" | 300 or 500 ||  || 0 or -5 || ES
|-
| _Electrical 78's (general) || 1947-1954 ||  ||  || 300 or 500 ||  || -16 || ES
|-
| Aco || 1926 - 1933, with M in a circle || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Aeolian-Vocalion || 1926 - 1933, with M in a circle || style="white-space: nowrap;" | BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| American Rec. Co. ||  ||  ||  || 500 ||  || ? || PC
|-
| Argo ||  || American 78 || 250N-6 || 250 || N || -6 || mm
|-
| Ariel || 1925 - 1931 UK, with Δ after matrix no. or with W in a circle || [W.E.] ||  || 250 ||  || W.E.mike || PC
|-
| Artist ||  ||  ||  || 500 ||  || -16 || ES
|-
| Audiophile || 1948-1958 || Audiophile || 500N-8 || 500 || N || -8 || mm
|-
| Autograph  || Marsh electrical ||  ||  || 1000 ||  || 0 || ES
|-
| 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 || N || -5,7 || PC
|-
| Bluebird || sub-label of RCA, see: RCA-Victor ||  ||  ||  ||  ||  || ES
|-
| 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
|-
| Bluebird || 1932 - 1949, with High Cut at 8500Hz || 500-FLAT ||  || 500 ||  || 0, later -12 || PC
|-
| Broadcast ||  || American 78 || 250N-6 || 250 || N || -6 || mm
|-
| Broadcast || 1926 - 1933, with M in a circle || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Brunswick || 1925 ||style="white-space: nowrap;" | European 78 || 250N-0 || 250 || N || 0 || ES,GH
|-
| Brunswick || 1944 - 1955, ffrr, a Brit. Decca label || Decca 78 || 300N-5.5 || 300 || N || -5,7 || PC
|-
| Brunswick || 1946 ||  || 500N-16 || 500 ||  || -16 || ES
|-
| Brunswick (American) ||  || 500-FLAT || 500N-0 || 500 || N || 0 || ia,JP,RF,PC
|-
| Brunswick || to 1951 ||  || 630N-8 || 629 || N || -8 || mm
|-
| Brunswick  || 1946 - 1954 ||  || 630N-12 || 629 ||  || -12 || ES 
|-
| Capitol || earliest 78s ||  ||  || 1000 ||  ||  || PC
|-
| Capitol || 1942 (founded) to 1951 || American 78 || 250N-8 || 250 || N || -8 || mm
|-
| Capitol || 1942 - ?;  probably "Capitol 400N-12.7" || [CAP] ||  || 400 ||  || -12 || ia,ES,mil,JP,RF
|-
| Capitol / Capitol Cetra || 1951-1955 || Capitol [CAP] || 400N-12.7 || 400 || N || -12,7 || mm
|-
| Capitol || to 1954  ||  ||  || 800 ||  || -10 || ES
|-
| Capitol - Telefunken  ||  || 500-FLAT || 500N-0 || 500 || N || 0 || ES,mil
|-
| Capitol (Europ.) || 1944 - 1955, ffrr, prod. by Decca UK, matrix prefix DCAP || Decca 78 || 300N-5.5 || 300 || N || -5,7 || PC
|-
| Cetra || founded 1930s by RAI, Italy || European 78 || 250N-0 || 250 || N || 0 || GH
|-
| Cetra-Soria || founded 1949, Cetra prod. in US || European 78 || 250N-0 || 250 || N || 0 || mm
|-
| Chappell || 1931 - 1944, with © before matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| Coliseum || 1926 - 1933, with M in a circle || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Columbia (American) || 1926   [W.E.] || American 78 || 250N-5 || 250 || N || -5 || ES,mil
|-
| Columbia (American) || 1926   [W.E.] ||  ||  || 200 ||  || -7 || ia,mil,JP,RF
|-
| Columbia (American) || 1926 - 1940 (?)   [W.E.] || American 78 || 250N-8 || 250 || N || -8 || mm
|-
| Columbia (American) || 1938 - end,  most ("Columbia Rec." a CBS label since 1938) || Columbia 78 || 300N-16 || 300 || N || -16 || ia,GH,ES,mil,mm,JP,RF
|-
| Columbia (British) || 1925 - 1931, with W in a circle || [W.E.] ||  || 250 ||  || W.E.mike || PC
|-
| Columbia (British) || from 1926, from 1931 EMI(UK) - 1953 || European 78 || 250N-0 || 250 || N || 0 || ia,GH,ES,JP,RF
|-
| Columbia (British) || 1931 - 1944, with © before matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 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 || N || 0 || PC
|-
| Concert Hall ||  ||  ||  || 500 ||  || -5 || ES
|-
| Coral  || 1946 - 1954  ||  ||  || 629 ||  || -12 || ES
|-
| Coral  ||  || AES || 400N-12 || 400 || N || -12 || ES,JP
|-
| Decca (American) || 1934 -,  (Decca US established in 1934) || AES || 400N-12 || 400 || N || -12 || ia,JP,RF
|-
| Decca (American) || pre 1946 || Blumlein300 || 300N-0 || 300 || N || 0 || ES
|-
| Decca (American) || very few, to try a combination of 500Hz / 6300 Hz ||  || 500N-5.5 || 500 || N || -5,5 || mm
|-
| Decca (American) || 1946 - 1951 || Decca 78 || 300N-5.5 || 300 || N || -5,7 || mm
|-
| Decca (American) || 1946 - 1954  (??? 629 Hz ???) ||  ||  || 629 ||  || -12 || ES
|-
| Decca (American) || 1951 - 1953 || AES || 400N-12 || 400 || N || -12 || mm
|-
| Decca (American) || 1953-Nov 1955 || NAB || 500B-16 || 500 || B || -16 || mm
|-
| Decca (British) || 1935 - 1944, matrix up to DR8485-2; test disc: Decca K.1803, London T.4997 || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| Decca (British) || to 1944 || European 78 || 250N-0 || 250 || N || 0 || ES,mm
|-
| 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 || N || -5,7 || PC
|-
| Decca (British) || 1944 - 1956 || Decca 78 || 300N-5.5 || 300 || N || -5,7 || ES,mm
|-
| Decca (British) || some 1949-1956 || London LP || 500C-10.5 || 500 || C || -10,5 || mm
|-
| Decca (European) || to 1944 || European 78 || 250N-0 || 250 || N || 0 || mm
|-
| Decca (European) || 1944-1950 || Decca 78 || 300N-5.5 || 300 || N || -5,7 || ES,mm
|-
| Decca (European) || 1950-1954, (Telefunken + Decca UK = TELDEC since 1950) || Telefunken || 400N-0 || 400 || N || 0 || mm
|-
| Decca (European) || some 1954-1962 || CCIR 78 || 350N-10.5 || 354 || N || -10,5 || mm
|-
| Decca ffrr || 1946, same as London ffrr || Decca 78 || 300N-5.5 || 300 || N || -5,7 || ia,mil,JP,RF
|-
| Deutsche  Grammophon  || alias "DGG", taken over by Telefunken 1937 ||  ||  || 300 ||  || -5 || ES,mil
|-
| Deutsche Grammophon || 1944 ca. - 1953 ca. (???) || European 78 || 250N-0 || 250 || N || 0 || PC
|-
| Dial  || 78s used same EQ as 33⅓ and 45s || Columbia LP || 500C-16 || 500 || C || -16 || ES,mil
|-
| Dot || to 1958 || AES || 400N-12 || 400 || N || -12 || mm
|-
| Electrola  ||  ||  ||  || 800 ||  || -10 || ES,mil
|-
| EMI-HMV (British) || some, re-releases of acoustics mastered 1909-1926  ||  || 800N-12 || 800 || N || -12 || mm
|-
| EMI-HMV (British) || 1927 - 1953, prod. by EMI(UK) || European 78 || 250N-0 || 250 || N || 0 || GH,ES,mil,mm
|-
| EMI-HMV (British) || 1931 - 1944, with □ after matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 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 || N || 0 || ia,ES,mil,JP,RF,PC
|-
| EMI-HMV (British) || 11/1943 - 7/1953, matrix nos. from 2EA17501 to 0EA17576 || European 78 || 250N-0 || 250 || N || 0 || PC
|-
| EMI-HMV (British) || 1955 - end, test disc: EMI JGS812, BBC DOM86 || CCIR 78 || 350N-10.5 || 354 || N || -10,5 || PC
|-
| Exclusive || all, 1944 - 1949 || Decca 78 || 300N-5.5 || 300 || N || -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 || N || 0 || ES,mil
|-
| Harmony Acoustics  || to Aug 1929 ||  ||  || 300 ||  || -16 || mil
|-
| His Master's Voice (Brit.) || some, re-releases of acoustics mastered 1909-1926  ||  || 800N-12 || 800 || N || -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.) || 1927 - 1953, prod. by EMI(UK) || European 78 || 250N-0 || 250 || N || 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 || N || 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 || ES,mil
|-
| 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 || N || 0 || PC
|-
| Keynote ||  || 500-FLAT || 500N-0 || 500 || N || 0 || ES
|-
| King  ||  ||  ||  || 500 ||  || -16 || ES,mil
|-
| Linguaphone || 1926 - 1933, with M in a circle || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Linguaphone  ||  || Blumlein300 || 300N-0 || 300 || N || 0 || ES,mil
|-
| L'Oiseau-Lyre || 1944 - 1955, ffrr, prod. by Decca UK, || Decca 78 || 300N-5.5 || 300 || N || -5,7 || PC
|-
| London  || early ,  1947-1948 ? || European 78 || 250N-0 || 250 || N || 0 || mil
|-
| London || 1947 - 1955, ffrr, prod. by Decca UK, || Decca 78 || 300N-5.5 || 300 || N || -5,7 || PC
|-
| London ffrr || 1949,   same as Decca ffrr (to DR8485-2)  || Decca 78 || 300N-5.5 || 300 || N || -5,7 || ia,mil,JP,RF
|-
| MacGregor || to 1965? || American 78 || 250N-8 || 250 || N || -8 || mm
|-
| Majestic ||  ||  ||  || 500 ||  || -16 || ES
|-
| Marsh Laboratories  || (electrical)  ||  ||  || 1000 ||  || 0 || ES
|-
| Mercury || to 1951 || American 78 || 250N-8 || 250 || N || -8 || mm
|-
| Mercury || 1951 - Oct 1954;  to matrix MG50026, 7000 || AES || 400N-12 || 400 || N || -12 || ia,ES,mm,JP,RF
|-
| MGM (American) || founded 1946;  up to E3071 || MGM [MGM] || 500N-12 || 500 || N || -12 || ia,ES,mil,JP,RF
|-
| MGM (British) || 1949 - 7/1953, matrix no. 0SM420 || 500-FLAT || 500N-0 || 500 || N || 0 || PC
|-
| Musicraft ||   ||  ||  || 800 ||  || RIAA || ES
|-
| Musicraft  ||  ||  ||  || 700 or 750 ||  || -14 || ES,mil
|-
| Nat. Gramophonic Soc. || 1926 - 1933, with M in a circle, cat. HHH to TTT and NGS.65 to NGS.102 || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Octacros || 1931 - ?, Britain, a Synchrophone label || Blumlein300 || 300N-0 || 300 || N || 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) ||  ||  || 400 || 100Hz || 0 || PC
|-
| Odeon || 1931 - 1944, with © before matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| Odeon  || to 1953, (1926 sub. of Brit. Columbia , 1931 sub. of EMI) || Blumlein300 || 300N-0 || 300 || N || 0 || ES,mil
|-
| OKeh || 1926 - 1941 (a Columbia label since 1926) || American 78 || 250N-8 || 250 || N || -8 || mm
|-
| OKeh || electricals,  probably American78 250N-8  ||  ||  || 300 ||  || 0 or -8.5  || ES,mil
|-
| OKeh || 1941 - ||  || 400N-8 || 400 || N || -8 || mm
|-
| Parlophone || 1925 - 1931, with W in a circle || [W.E.] ||  || 250 ||  || W.E.mike || PC
|-
| Parlophone || 1925 - 1953 || European 78 || 250N-0 || 250 || N || 0 || GH,ES
|-
| Parlophone || 1931 - 1944, with © before matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| Parlophone || 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 || 1949 - 7/1953, EMI UK, matrix nos. from CE14643 to CE14689 || 500-FLAT || 500N-0 || 500 || N || 0 || ia,PC,JP,RF
|-
| Parlophone-Odeon || 1925 - 1928, with W in a circle, Odeon in Brit. || [W.E.] ||  || 250 ||  || W.E.mike || PC
|-
| Parlophone-Odeon || 1928/29, matrix with ₤ in a circle, Odeon in Brit. ||  ||  || 400 || 100Hz || 0 || PC
|-
| Pathé || 1931 - 1944, with © before matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| Philips || to 1953 || Philips || 400N-6 || 400 || N || -6 || mm
|-
| Polydor  || sub-label of Deutsche Grammophon ||  ||  || 300 ||  ||  -8,5 or -10 || ES,mil
|-
| Radiofunken  ||  || Telefunken || 400N-0 || 400 || N || 0 || mil
|-
| RCA Victor || 12/1931 - 2/1932 "long-playing" shellacs at 33⅓ rpm ||  ||  || 500 - 700 ||  || 0 || PC
|-
| RCA Victor || 1931/2 "long-playing" shellac, N-groove played at 33⅓ || American 78 || 250N-6 || 250 || N || -6 || mm
|-
| RCA Victor || 1931 - , test disc Victor84522 || 500-FLAT || 500N-0 || 500 || N || 0 || PC,ES
|-
| RCA Victor || 1931 - ?, with swastika after matrix no., (EMI reissues) || European 78 || 250N-0 || 250 || N || 0 || PC
|-
| RCA Victor || 1931 - 1941 || American 78 || 250N-6 || 250 || N || -6 || mm
|-
| RCA Victor || 1931 - 1944, with □ after matrix no., EMI UK reissues,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| RCA Victor || 1933 ||  ||  || 375 ||  || -8,5 || mil
|-
| RCA Victor || 1935 ||  ||  || 300 or 500 ||  || -5 || ES
|-
| RCA Victor /Victrola || 1932 - 1949, with High Cut at 8500Hz || 500-FLAT ||  || 500 ||  || 0, later -12 || PC
|-
| RCA Victor || 1938 (or earlier), used High Cut at 8500Hz || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || PC
|-
| RCA Victor || 1938 - 1947 ||  ||  || 500 ||  || -7 || ia,JP,RF
|-
| RCA Victor || 1938 - 1948  ||  ||  || 500 ||  || 0 to -12  || mil
|-
| RCA Victor || 1938 - 1954 ||  ||  || 500 ||  || -8 || ES,mil
|-
| RCA Victor || 1941 - 1947 (some to Sept 1952) || Old RCA || 800N-8 || 800 || N || -8 || mm
|-
| RCA Victor || 1947 - 1951 || RCA 45 || 800N-12.3 || 800 || N || -13,8 || mm
|-
| RCA Victor || 1947 (or 1950) - Aug 1952 || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || ia,mm,JP,RF
|-
| RCA Victor || RIAA after 8/52, after matrix E2RP4094 || RIAA || 500R-13.7 || 500 || R || -13,7 || ES
|-
| RCA Victor (European) || 1930 - 1950 || European 78 || 250N-0 || 250 || N || 0 || ES
|-
| Regal || 1925 - 1931 UK, 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 || N || 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 || N || 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 || N || 0 || PC
|-
| 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 || N || 0 || ES,mil
|-
| Synchrophone || 1931 - ?, Britain || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|-
| Technichord || American, all N78 from 1938   [TCH] || Technichord || 800N-12 || 800 || N || -12 || ES,mil,mm
|-
| Telefunken || 1944 - 1955, ffrr, prod. by Decca UK, || Decca 78 || 300N-5.5 || 300 || N || -5,7 || mm,PC
|-
| Telefunken || 1951-1953,  (Telefunken + Decca UK = TELDEC since 1950) || Telefunken || 400N-0 || 400 || N || 0 || mm
|-
| Tempo (American) ||  ||  || 400N-6 || 400 || N || -6 || mm
|-
| Theme || all N78 || American 78 || 250N-6 || 250 || N || -6 || mm
|-
| Turicaphon || Switzerland, 1930 - , a subsid.of Ultraphon || Telefunken || 400N-0 || 400 || N || 0 || 
|-
| Ultraphon || Europe 1929-1932, taken over by Telefunken || Telefunken || 400N-0 || 400 || N || 0 || ES,mil
|-
| Unison || 1926 - 1933, with M in a circle || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Victor || 1925    [W.E.] ||  ||  || 200 - 500 ||  || -7 || ia,JP,RF
|-
| Victor || 1925    [W.E.] ||  ||  || 250 or 300  ||  || 0 or -5  || ES,mil
|-
| Victor || 1926 -1931   [W.E.] || American 78 || 250N-6 || 250 || N || -6 || mm
|-
| 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
|-
| Victor || see: RCA-Victor (bougt by RCA in 1930) ||  ||  ||  ||  ||  || ES
|-
| Vocalion  || a Brunswick label, 1926 - 1940 || European 78 || 250N-0 || 250 || N || 0 || ES,mil
|-
| Vocalion || 1926 - 1933, to cat. X10029 A.0269 and K05312, with M in a circle || BBC 2dB/oct. ||  ||  ||  ||  || PC
|-
| Vocalion || 1944 - 1955, ffrr, prod. by Decca UK, series V1000 || Decca 78 || 300N-5.5 || 300 || N || -5,7 || PC
|-
| Voice of the Stars || 1931 - 1944, with © before matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 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 || N || 0 || PC
|-
| Zonophone  || 1931 - 1944, with □ after matrix no.,  [Bc] || Blumlein300 || 300N-0 || 300 || N || 0 || PC
|}

<div id="RemarksTab2"></div>
:::'''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 describes it correctly as 234Hz / 1989Hz but 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!
:::*[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.
:::*[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 [http://audacity.lifey.at/Early%20Western%20Electric%20Characteristic.pdf this PDF].  An experimental replay EQ curve for this microphone / pre-emphasis combination can be downloaded [[Media:Western_Electric_2.1.2.XML|‎here]].
:::*[MGM] ... and Audiophile used a special '''“MGM curve”''' 500N-12.  Play back with “RCA Old Orthophonic” 500N-12.3!  
:::*[TCH] ... Technichord used its own '''“Technichord curve”''' 800N-12.  Play back with “RCA 45” 800N-12.3!

:::'''Sources:'''
:::*Hi ... High Fidelity Magazine, October 1955  with revised “Dialing Your Disks” table.
:::*ES ... [http://www.esotericsound.com/ Esoteric Sound] and the updated EQ list from the [http://www.esotericsound.com/Electronics/REQ2MAN.pdf manual] of their re-equalizer preamp  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
:::*ia ... iasa – International Association of Sound and Audiovisual Archives:  [http://www.iasa-web.org/tc04/mechanical-carriers-replay-equalisation 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
:::*mil ... [http://www.mil-media.com/index.html Millennia Music and Media Systems] and their list MM Legacy Recordings:  [http://www.mil-media.com/pdf/Millennia 78 EQ Chart.pdf]
:::*mm ... [http://midimagic.sgc-hosting.com/mixlabls.htm MidiMagic] is probably the most comprehensive and reliable websource.  Data were researched in the 1970s and are based on publications of the 1950s.      
:::*RB ... Richard Brice in [http://pspatialaudio.com/record_characters.htm PspatialAudio]  
:::*RF ... Russell Fisher / [http://www.shellac.org/wams/wequal.html W.A.M.S.] (Wolverine Antique Music Society) 
:::*PC ...Peter Copeland, [http://www.bl.uk/help/manual-of-analogue-audio-restoration-techniques Manual] of Analogue Sound Restoration Techniques, The British Library, 2014,  (Some of Copeland’s EQ curves or sources are disputable!)

:::'''Recommended analog reference:'''  
:::*James R. Powell, Jr. and Randall G. Stehle, "Playback Equalizer Settings for 78 RPM Recordings", Third Edition, Gramophone Adventures, Portage, MI, 1993, 2002, 2007.
:::*Fritz Langford-Smith, Radiotron Designer's Handbook, Wireless Press, Sydney, Fourth edition, 1952.
:::*James Moir, High Quality Sound Reproduction, Chapman & Hall Ltd., London, 1958 





==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.

In case that sources did not agree on one EQ curve, their different opinions are listed and you will have to trust your ears.  Later recordings on the labels listed should be all RIAA.  The following labels should have used only RIAA all the time:  Bethlehem, Classic Editions, Chess, Clef, Composer Recordings, McIntosh, Montilla, New Jazz, Norgram, Prestige, Romany, Roulette, Savoy and Walden [High Fidelity Magazine, MidiMagic].


<div id="table_3"></div>
'''''Table 3: Early 33⅓ LP Labels And Their EQ'''''

{| class="wikitable" style="background:#F2F8FF; color:#002757;"
! Label !! Remarks !! Curve Name !! Code !! turnover <br> bass [Hz] !! bass <br> shelf !! treble rolloff <br> [dB @ 10kHz] !! Source
|-
| Allegro || 1948 - 1956 || style="white-space: nowrap;" | Columbia LP || 500C-16 || 500 || C || -16 || ES
|-
| Allied ||  || ???NAB ||  || 500 ||  || -16 || JP
|-
| Allied || to 1958 || Columbia LP || 500C-16 || 500 || C || -16 || Hi,ES,mil,mm
|-
| style="white-space: nowrap;" | American Recording Society || to 1958 || AES || 400N-12 || 400 || N || -12 || Hi,mm,JP
|-
| American Recording Society || to matrix E2KP9607 ||  ||  || 500 ||  || -12 || ES
|-
| Angel  || (2XEA213-392/XAX561-817)(1N,2N)  || 500-FLAT || 500N-0 || 500 || N || 0 || ES
|-
| Angel || to 1952;   to 35022 || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || ES,mil,mm,RF
|-
| Argo ||  || RIAA || 500R-13.7 || 500 || R || -13,7 || mm
|-
| 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 || NAB || 500B-16 || 500 || B || -16 || ES,mil,mm,JP
|-
| Audio Fidelity || no. 901-903 || NAB || 500B-16 || 500 || B || -16 || ES,mm,JP,RF
|-
| Audiophile || 1954 - 1958 (!) || MGM  [MGM] || 500N-12 || 500 || N || -12 || Hi,ES,mm,JP
|-
| Bach Guild || sub-label of Vanguard; to no. 500 || Columbia LP || 500C-16 || 500 || C || -16 || GH,mm
|-
| Bach Guild || no. 501-529. || style="white-space: nowrap;" | NAB or Col.LP || 500?-16 || 500 || B/C || -16 || Hi,ES,mil,mm,RF,<br>JP
|-
| Banner || to 10002 || Columbia LP || 500C-16 || 500 || C || -16 || ES,mil,mm
|-
| Bartok || to 1952 || Columbia LP || 500C-16 || 500 || C || -16 || ES,mm
|-
| Bartok || 1952-1953 || AES || 400N-12 || 400 || N || -12 || mm
|-
| Bartok || no. 301-307, 309, 906-920 || Bartok || 630C-16 || 629 || C || -16 || ES,mil,mm,JP,RF
|-
| Bartok || 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 || 400 || N || -12 || Hi,ES,mil,mm,JP
|-
| Bluebird || sub-label of RCA, see: RCA-Victor ||  ||  ||  ||  ||  || ES
|-
| Boston || to 1958, up to B202 || Columbia LP || 500C-16 || 500 || C || -16 || Hi,ES,mil,mm,JP,<br>RF
|-
| Brunswick || to matrix MG4400;  early "T" || Columbia LP || 500C-16 || 500 || C || -16 || ES
|-
| Brunswick  || to matrix MG4400;  with raised matrix**  || Old RCA || 800N-8 || 800 || N || -8 || ES
|-
| Brunswick || 1951-1955 || AES || 400N-12 || 400 || N || -12 || mm
|-
| Caedmon || founded 1952, TC1002 - TC1022 (1955) || Bartok || 630N-16 || 629 || N || -16 || Hi,ES,mil,mm,JP,<br>RF
|-
| Caedmon  ||  ||  ||  || 629 ||  ||style="white-space: nowrap;" |  -11 or -12 || JP,ES
|-
| Caedmon || 1953 - ?, early LPs (!) || CCIR 78 || 350N-10.5 || 350 || N || -10,5 || PC
|-
| Canyon || to C6160 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,JP
|-
| 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
|-
| 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 by 800 Hz t/o  ||  ||  || 500 ||  || -12 || ES
|-
| Capitol (American) || 1951 - 1955;  possibly "Capitol 400N-12.7" || AES || 400N-12 || 400 || N || -12 || PC,JP,RF
|-
| 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,<br>RF
|-
| Colosseum ||  || AES || 400N-12 || 400 || N || -12 || ES,mil,RF
|-
| 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,<br>JP,RF
|-
| Columbia (American) || 1948 - 1953;  45 rpm || NAB || 500B-16 || 500 || B || -16 || ES,mm
|-
| Columbia (American) || 45 rpm || AES || 400N-12 || 400 || N || -12 || 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) || to 1954,   XTV matrix to 20383 (low take nos)  || Columbia LP || 500C-16 || 500 || C || -16 || Hi,ES,mm,JP,RF
|-
| Concert Hall || E1KP/E2KP matrix || ???AES ||  || 500 ||  || -12 || ES
|-
| Concert Hall || marked AES, E1KP / E2KP matrix || AES || 400N-12 || 400 || N || -12 || ES,mil,mm,RF
|-
| Concert Hall || E0 matrix || Old RCA || 800N-8 || 800 || N || -8 || ES
|-
| 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 || 400 || N || -12 || Hi,ES,mm,JP
|-
| 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 rolloff, outs.-11 dB ||  ||  || 500 ||  || style="white-space: nowrap;" |0 ins./-11 outs. || Hi,ES,mil,mm
|-
| Coral ||  || ???AES ||  || 400 ||  || -12 || JP
|-
| Coral || est. 1949, to 1958(?);  a DECCA subsidiary || NAB || 500B-16 || 500 || B || -16 || Hi,mm,JP
|-
| Coral || sub of Decca (Amer.) up to MG4400,  with raised matrix || Old RCA || 800N-8 || 800 || N || -8 || ES
|-
| Coral  ||  ||  ||  || style="white-space: nowrap;" |400 or 750  ||  ||style="white-space: nowrap;" | -12 or -16  || mil
|-
| Decca (American) || 1949-1951 || London LP || 500C-10.5 || 500 || C || -10,5 || mm
|-
| Decca (American) || 1953,  33⅓ and 45 rpm || AES || 400N-12 || 400 || N || -12 || mm,JP,RF
|-
| Decca (American) || 1953 - Nov 1955,  33⅓ and 45 rpm || NAB || 500B-16 || 500 || B || -16 || Hi,mm,JP,RF
|-
| Decca (American) || up to MG4400,  with raised matrix || Old RCA || 800N-8 || 800 || N || -8 || ES
|-
| Decca (British) || 1949-1956 || 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
|-
| Decca ffrr  || 1953 [author's note: London LP since 1949] || ???London ||  || 450 ||  ||  -10 or -11 || JP,RF
|-
| Deutsche  Grammophon  || alias "DGG" ||  ||  || LP ||  || -10 || ES
|-
| Deutsche Grammophon || 1952 - 1955, early LPs (!), cat. no in a rectangle || IEC N78 || 350A-10.5 || 350 || (50Hz) || -10,5 || PC,GH,RB
|-
| Deutsche Grammophon || RIAA, 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 || Columbia LP || 500C-16 || 500 || C || -16 || ES,mil,mm,JP
|-
| Dial || bass of EP 45s can be improved by 700Hz t/o ||  ||  || 500 ||  || -16 || ES
|-
| Dot || to 1958, 33⅓ and 45 rpm || AES || 400N-12 || 400 || N || -12 || mm
|-
| Ducretet Thomson || 10/1954 - 1958,  issued by London/Decca UK || ???London ||  || 450 ||  || -11 || RF
|-
| Elektra || EKL 17, 22 (released 1954) || AES || 400N-12 || 400 || N || -12 || Hi,ES,mm,JP
|-
| Elektra || EKL 2-15, 18-20, 24-26 (rel. 1952-55) || Bartok || 630N-16 || 629 || N || -16 || Hi,ES,mil,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. || 500N-12.3 || 500 || N || -12,6 || 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 || 33⅓ LP    ??? Columbia LP ??? ||  ||  || 500 ||  || -12 || mil
|-
| EMI-HMV || from July 17, 1953 || RIAA || 500R-13.7 || 500 || R || -13,7 || ES,PC
|-
| EMS || 1951 - 1956 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,JP,<br>RF
|-
| Epic || 1948 - 1954 || Columbia LP || 500C-16 || 500 || C || -16 || ES,mil,mm,JP,RF
|-
| Esoteric || ES 500,517 and EST 5,6 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,RF,<br>JP
|-
| Esoteric || matrix E2KP to 9607 ||  ||  || 500 ||  || -12 || ES
|-
| Festival || to 1955 || Columbia LP || 500C-16 || 500 || C || -16 || ES,mil,mm
|-
| Folkways || 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 ||  3, 9-19 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,JP
|-
| Good-Time Jazz ||  1, 5-8 || NAB || 500B-16 || 500 || B || -16 || Hi,ES,mm,JP
|-
| Good-Time Jazz ||  2, 4, 20 -; from Oct 1955, re-recording || RIAA || 500R-13.7 || 500 || R || -13,7 || Hi,mm
|-
| Handel Society || to 1957 || Columbia LP || 500C-16 || 500 || C || -16 || ES,mil,mm
|-
| Haydn Society || 1948 - 1955; to matrix XTV20386, HS3062, HS80 || Columbia LP || 500C-16 || 500 || C || -16 || Hi,ES,mil,mm,JP,<br>RF,PC
|-
| His Master's Voice (Amer.) || to 1951 || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || ES
|-
| His Master's Voice (Amer.) || 1951 - 1954 || NAB || 500B-16 || 500 || B || -16 || mm
|-
| His Master's Voice (Amer.) || 1954 - 1958(?) || Columbia LP || 500C-16 || 500 || C || -16 || Hi,mm
|-
| His Master's Voice (Amer.) || prod. by RCA after 1953 || RIAA || 500R-13.7 || 500 || R || -13,7 || GH
|-
| 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,<br>RF
|-
| London || first few || Columbia LP || 500C-16 || 500 || C || -16 || mm
|-
| London || 1953 - ; ffrr; to cat.no. 846 || ???London ||  || 450 ||  ||  -10 or -11 || JP,RF
|-
| London || to LL-846 || London LP || 500C-10.5 || 500 || C || -10,5 || Hi,mil,mm
|-
| London  || ffrr; after matrix ARL1186-1B***  || ???London ||  || 500 ||  || -10 || ES
|-
| London  || ffrr after 6/1950***  || 500-FLAT || 500N-0 || 500 || N || 0 || ES
|-
| London  || ffrr; after matrix ARL2530-2A || RIAA || 500R-13.7 || 500 || R || -13,7 || ES
|-
| Lyrichord || 1948 - 1951 || Columbia LP || 500C-16 || 500 || C || -16 || mil,mm,JP,RF
|-
| Lyrichord || 1951 - 1957(?) || NAB || 500B-16 || 500 || B || -16 || Hi,mm
|-
| Lyrichord || 1950 - ?, mastered by RCA || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || PC
|-
| Lyrichord ||  ||  ||  || 400 ||  || -16 || mil,JP,RF
|-
| Lyrichord  || before 1953, (E0-E3 matrix) || ???AES ||  || 400 ||  || -12 || ES
|-
| Lyrichord  || if "629" listed on jacket,  "newer" || Bartok || 630C-16 || 629 || C || -16 || ES,mil,JP,RF
|-
| Lyrichord  || XTV matrix || NAB or Col.LP || 500?-16 || 500 || B/C || -16 || ES
|-
| Mercury || 1948 - 1952, marked "2000Hz/3dB p.octave", MG10000 series ||  ||  || 500 ||  || -7 || PC,ES
|-
| Mercury || 1951(53?) - Oct 1954,  33⅓ and 45s, to matrix MG50026, 7000 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,JP,<br>RF,PC
|-
| MGM || to 1952 || NAB || 500B-16 || 500 || B || -16 || GH,mm
|-
| MGM ||  to 1952 a few; to matrix E3071; 33⅓ and 45 rpm; bass of 45s can be improved by 700 Hz t/o and rumble filter || MGM  [MGM] || 500N-12 || 500 || N || -12 || ES,mm,JP,RF
|-
| MGM || ??? MGM curve still used in Oct 1955 ??? || MGM  [MGM] || 500N-12 || 500 || N || -12 || Hi
|-
| 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  ||  ||  ||  || 500 ||  || -12 || 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 || 400 || N || -12 || 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. || 500N-12.3 || 500 || N || -12,6 || PC
|-
| Nixa (British) || US matrixes from Lyrichord;  see: Lyrichord ||  ||  ||  ||  ||  || PC
|-
| Nocturne || LP1-LP3 ,LP5; XP1-XP10 || AES || 400N-12 || 400 || N || -12 || 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,<br>RF
|-
| Odeon ||  ||  ||  || 300 ||  || -10 || ES
|-
| Overtone || no. 1-3;  to matrix XTV20386 || NAB || 500B-16 || 500 || B || -16 || Hi,ES,mil,mm,JP,<br>RF
|-
| Overtone  || up to matrix XTV20383 (low take nos.)  || ???Col.LP ||  || 500 ||  || -16 || ES
|-
| 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 || 400 || N || -12 || 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
|-
| Philharmonia || to 1958? || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,JP
|-
| 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 ||  ||  -8,5 or -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 rolloff, 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 - 8/1952,  some, (D9 to EOLRC3980)#   33⅓ and 45s || Old RCA || 800N-8 || 800 || N || -8 || ES,mm
|-
| RCA Victor || 1949 - 8/1952, first 45 rpm discs (also some M33) || RCA 45 || 800N-12.3 || 800 || N || -13,8 || mm,PC
|-
| RCA Victor || 1950 - 8/1952, 33⅓ only (matrix to E0LRC3981) || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || ES,mil,mm,JP,RF,<br>PC
|-
| RCA Victor || Aug. 1952, "New Orthophonic"; all LM,WDM,DM cat. from 1701; LCT,WCT from 1112; all LHMV,WHMV,LBC,WBC and Ext. Play 45s; (from E2RP4094) || RIAA || 500R-13.7 || 500 || R || -13,7 || Hi,GH,ES,PC
|-
| RCA Victor || 1948 ||  ||  || 500 ||  || -10,5 || mil
|-
| RCA Victor || 1949; matrix D9 to EOLRC3980;  33⅓ and 45s ||  ||  || 700 ||  || -10 || ES
|-
| Remington || to 1958(?); to matrix 199-135 || NAB || 500B-16 || 500 || B || -16 || Hi,ES,mil,mm,JP,<br>RF
|-
| Renaissance || 1949 - 1952 || Columbia LP || 500C-16 || 500 || C || -16 || mm
|-
| Renaissance || 1952 - 1954 || Pacific Jazz || 500C-12 || 500 || C || -12 || ES,mil,mm
|-
| Riverside || to Sept (?) 1955 || AES || 400N-12 || 400 || N || -12 || 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 || ES,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 || to 1954;  most   (up to XTV20383)(low take nos)  || Columbia LP || 500C-16 || 500 || C || -16 || mil,mm,JP,RF,ES
|-
| Urania ||  224, 603, 7059, 7063, 7065-66, 7069 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mm,JP,RF
|-
| Urania || 1950 - ?, mastered by RCA;  (to E2KP9607)  || Old Ortho. || 500N-12.3 || 500 || N || -12,6 || PC,ES
|-
| Vanguard || 1948 - 1951 || Columbia LP || 500C-16 || 500 || C || -16 || GH,mm
|-
| Vanguard || 1952 - 1953; VRS 411-42, 6000-18, 7001-11, 8001-04, (up to XTV20386) || NAB or Col.LP || 500?-16 || 500 || B/C || -16 || Hi,ES,mil,JP,RF
|-
| Vanguard || since ca 1954 || RIAA || 500R-13.7 || 500 || R || -13,7 || Hi
|-
| Vox || 1948 - 1951(55?) or labeled "LP" (up to XTV20386), PL8400) || Columbia LP || 500C-16 || 500 || C || -16 || GH,mil,mm,JP,ES,<br>PC
|-
| Vox || labeled AES || AES || 400N-12 || 400 || N || -12 || 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. || Columbia LP || 500C-16 || 500 || C || -16 || Hi,ES,mil,mm,JP,<br>RF,PC
|-
| Westminster || labeled AES;   to matrix E2KP 9607 || AES || 400N-12 || 400 || N || -12 || Hi,ES,mil,mm,JP,<br>RF
|-
| Westminster || labeled NARTB || NAB || 500B-16 || 500 || B || -16 || GH,JP 
|-
| Westminster  || EO matrix || Old RCA || 800N-8 || 800 || N || -8 || ES
|}

:::For Remarks and Sources please see [[#RemarksTab2|Remarks below Table 2]].