HiFi Loudspeaker Design

Calculate Active RIAA Network
for Old Vinyl ( 78 RPM )

Before 1955, every record company chose and applied its own version of recording equalization; there were over 100 combinations of turnover and rolloff frequencies in use, the main ones being Columbia-78, Decca-U.S., European (various), Victor-78 (various), Associated, BBC, NAB, Orthacoustic, World, Columbia LP, Decca ffrr 78 and microgroove, and AES.

By 1975, most audiophile amplifiers had banished tone controls, mono switches, and variable EQ selectors.

The most relevant EQ curves are presented in the overview below.
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.

Chosen Record Equalization :

Calculator

The form calculates the exact values for R1 to R3. Resistors are usually not available with exactly these values.
However, with a parallel circuit of two E24 resistors, you can often approximate these values quite good.
The calculator finds the two E24 resistor values that best matches the value.

C : nF = pF

F : Hz -

T1 = uS Pole #1

F : Hz -

T2 = uS Zero #1

F : Hz -

T3 = uS Pole #2

Calculated the resistor values of R1, R2 and R3

R1 = Ω = kΩ = MΩ

R2 = Ω = kΩ = MΩ

R3 = Ω = kΩ = MΩ

R1 =	Ω	parallel	Ω	=	Ω,	Error =	%
R2 =	Ω	parallel	Ω	=	Ω,	Error =	%
R3 =	Ω	parallel	Ω	=	Ω,	Error =	%

The most relevant EQ curves

( from Vinylengine.com )

* These eigth equalizations reflect most of the major variations found in 78, 45, and 33 1/3rpm gramophone recordings made between 1920 and 1965.

1) Old European Characteristic: "250"

HMV N78 (His Masters Voice) and Columbia N78 produced by E.M.I. England. CETRA N78, Italy.

This standard may be also applied to records by Parlophone, Brunswick

Time Constant: 636 µs (250 Hz).

Use this EQ parameters

2) Old European Characteristic: "500"

Applicable to many European records produced before 1950, and also to many U.S. companies except RCA Victor, Columbia.

Time Constant: 318 µs (500 Hz).

Use this EQ parameters

3) * Columbia N78

Time Constants: 530 µs (300 Hz) and 100 µs (1,590 Hz).

Use this EQ parameters

4) * Columbia LP M33

HMV M33, produced in England.

Vanguard, Bach Guild, Cetra M33, Vox.

Time Constants: 1,590 µs (100 Hz), 318 µs (500 Hz), and 100 µs (1,590 Hz).

Use this EQ parameters

5) * NAB National Association of Broadcasters

Time Constants: 530 µs (300 Hz) and 100 µs (1,590 Hz).

Use this EQ parameters

6) * NARTB National Association of Radio and TV Broadcasters

Has replaced NAB standard. Applicable to Artist, Capitol, MGM, Westminster, Tempo M33 (approximate char.)

Time Constants: 2,720 µs (60 Hz), 318 µs (500 Hz), and 100 µs (1,590 Hz).

Use this EQ parameters

7) * AES Audio Engineering Society

Made in 1951 this reproduction definition for compatibility to standards mostly used in the USA.

Time Constants: 398 µs (400 Hz) and 64 µs (2,500 Hz).

Use this EQ parameters

8) London Gramophone Corporation

London M33 & M45,Decca (possibly).

Time Constants: 1,590 µs (100 Hz), 318 µs (500 Hz), and 57 µs (2,800 Hz).

Use this EQ parameters

9) * CCIR Recommendation No. 134

By VIIth Plenary Assembly, 1953: Germany 1952-1955: DGG 33 1/3 LP.

Time Constants: 450 µs (350 Hz), and 50 µs (3,180 Hz).

Use this EQ parameters

10) IEC

A recommendation of 1955 for playing N78 disks, according to B.S. No. 128 (British Standard).

Time Constants: 3180 µs (50 Hz), 450 µs (350 Hz), and 50 µs (3,180 Hz).

Use this EQ parameters

11) * RCA Victor & IEC No.98

Refers to this "New Orthophonic" standard since 1952.

Recommendation of 1953 by NARTB, of 1955 by IEC No.98, and B.S. No. 128. World standard since 1967.

Time Constants: 3180 µs (50 Hz), 318 µs (500 Hz), and 75 µs (2,120 Hz).

Use this EQ parameters

12) * RIAA, TELDEC

Telefunken and Decca founded a record company that used a characteristic proposed for German DIN-Standard on July 1957:

DIN45533, DIN45536, DIN45537.

Time Constants: 3180 µs (50 Hz), 318 µs (500 Hz), and 50 µs (3,180 Hz).

Use this EQ parameters

Record Equalization

( from Vinylengine.com )

The following table contains specifications for correct playback of gramophone records recorded to non-RIAA standards.

	1	2	3	4	5	6	7	8	9	10	11	12
Hz	250	500	Columbia N78	Columbia LP M33	NAB	NARTB	AES	London	CCIR	IEC	RCA	Teldec
30	+18.2	+23.5	+21.1	+14.1	+25.0	+18.0	+22.5	+13.2	+21.3	+15.5	+18.6	+18.1
40	+15.7	+21.0	+18.7	+13.9	+22.5	+17.3	+20.0	+13.0	+18.8	+14.7	+17.8	+17.3
60	+12.3	+17.5	+15.2	+13.2	+19.0	+16.0	+16.6	+12.3	+15.3	+13.1	+16.1	+15.6
120	+7.0	+11.6	+9.7	+10.8	+13.1	+12.2	+10.9	+10.0	+9.7	+9.0	+11.8	+11.3
250	+2.7	+6.0	+4.9	+6.7	+7.4	+7.1	+5.5	+5.9	+4.6	+4.5	+6.7	+6.2
500	+0.7	+2.0	+2.0	+2.9	+3.1	+3.0	+2.0	+2.3	+1.5	+1.5	+2.6	+2.3
1000	0 db	0 db	0 db	0 db	0 db	0 db	0 db	0 db	0 db	0 db	0 db	0 db
2000	-0.2	-0.7	-2.9	-3.4	-3.4	-3.4	-2.0	-1.9	-1.4	-1.4	-2.6	-1.8
4000	-0.3	-0.9	-7.5	-8.1	-8.1	-8.1	-5.5	-5.1	-4.2	-4.2	-6.6	-4.7
6000	-0.3	-1.0	-10.7	-11.3	-11.3	-11.3	-8.3	-7.9	-6.7	-6.7	-9.6	-7.2
8000	-0.3	-1.0	-13.1	-13.7	-13.7	-13.7	-10.5	-10.0	-8.8	-8.8	-11.9	-9.3
10000	-0.3	-1.0	-15.0	-15.6	-15.6	-15.6	-12.3	-11.8	-10.5	-10.5	-13.8	-11.0
12000	-0.3	-1.0	-16.5	-17.1	-17.1	-17.1	-13.8	-13.3	-11.9	-11.9	-15.3	-12.4
15000	-0.3	-1.0	-18.4	-19.0	-19.0	-19.0	-15.7	-15.1	-13.8	-13.8	-17.2	-14.3

More info about RIAA Networks (very technical)

Useful information about RIAA Preamps

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