When was the RIAA curve established — years of pre-history leading up to January 29, 1954

When was the RIAA curve established?

Question answered on this page: When and how was the RIAA curve established? Why did it take so long?

In short

January 29, 1954. Officially approved by the Technical Committee of the RIAA (Recording Industry Association of America). The RIAA standard document circulated formally in June 1954 (this is the version cited by Bachman, Bauer, and Goldmark, "Disk Recording and Reproduction," Proc. IRE, 1962, as their reference).

However, this date is a finish line, not a starting point. The work to standardize disc recording began in the early 1940s, and it took over 10 years of discussion and trial to arrive at the RIAA curve. Moreover, even after approval, records cut with older curves continued to circulate for some time.

→ What is the RIAA curve? — definition of the curve and its three time constants

Standardization timeline

The following outlines the major standards leading up to the RIAA curve.

What is remarkable is that NARTB (broadcasters), AES (academic society), and RIAA (record industry) adopted nearly identical time constants in succession within just six months. This was because these organizations had overlapping memberships and were working in coordination to advance standardization.

The new RIAA curve was also essentially identical to RCA Victor's New Orthophonic curve, which was already in use. The AES curve, too, fell within ±2 dB above 40 Hz. This meant the new standard functioned as a practical "compromise point" that required no drastic equipment changes from most manufacturers.

→ The detailed history is covered in blog post Pt.18

After approval, unification didn't happen overnight

A July 1954 Radio News article titled "The Curve That Conforms" captures the industry's mood just after the RIAA curve was approved. It welcomed the new standard as a step forward, yet made clear that full unification would take time.

"After several futile attempts at standardizing the equalization curve, most manufacturers gave up and continued the status quo. At this point the powerful and influential Record Industry Association of America (RIAA) entered the fray, and now, happily, it is possible to report that the new 'RIAA Standard Record-Playback Curve' is being adopted throughout the record industry."

The article records comments from label representatives:

• Albert Pulley (RCA Victor): The new RIAA curve was identical to the "Orthophonic" that RCA had already been using. All new releases and reissues — including the "Treasury" series — would be cut with the RIAA curve wherever possible.
• William Bachman (Columbia): All new Columbia recordings were using the RIAA curve, and replacement pressings would be recut with it wherever possible.
• C. Robert Fine (Mercury): Mercury would go along with the industry in using the RIAA curve for all new releases.
• Remy van Wyck Farkas (London): London had been using the RIAA curve for some months. The entire back catalog would be recut as stocks of the older-curve pressings were depleted.
• Capitol / Decca / MGM: Capitol had already been using it; Decca and MGM would adopt it for future releases.
• Westminster: Dr. Kurt List stated that Westminster would continue with the old NAB curve for the time being. The article predicted they would "hop on the RIAA bandwagon before too long."

Two points stand out. First, while the labels broadly agreed on "RIAA for new releases," when back-catalog titles would be recut varied from label to label. Old-curve pressings would remain in circulation until stampers wore out or stocks were exhausted.

Second, as the article frankly acknowledged, there was no way to tell old-curve and new-curve pressings apart by looking at them:

"you will have no way of knowing whether an old recording has been recut with the new RIAA curve, or is still the original curve."

In other words, the RIAA's approval was a "finish line" and at the same time the start of a new problem: the transition period. Listeners still needed flexible preamplifiers capable of handling multiple curves.

→ When did each label switch to the RIAA curve? — label-by-label transition details

The debate over high-frequency pre-emphasis

The most contentious issue during the standardization process was the amount of high-frequency pre-emphasis.

The high-frequency time constant of the 1942 NAB curve was 100 μs (±16 dB at 10 kHz), but criticism that the high-frequency pre-emphasis was too strong, causing distortion, was repeatedly raised from within the standards committee. Specifically, as early as 1947, committee members clearly expressed the view that "100 μs should be lowered to 75 μs (±13.7 dB at 10 kHz)."

Ultimately, the 1953 NARTB standard revised the high-frequency time constant to 75 μs, and this value was adopted by the RIAA as is. This 75 μs value is the same as the high-frequency time constant of the New Orthophonic curve that RCA Victor had been using since around 1952.

→ For details on the high-frequency pre-emphasis debate, see The first-ever recording standard — the 1942 NAB (also blog post Pt.10)

Why did unification take so long?

It took 12 years from the first standardization in 1942 to the RIAA. Why so long? The main factors are as follows.

World War II (1941–1945). Immediately after the tentative NAB standard was established in 1942, the war intensified and standardization work was suspended. Committee work did not resume until 1947.

Confusion from the arrival of LPs and 45 rpm discs (1948–1950). With the introduction of the Columbia LP in 1948 and the RCA Victor 45 rpm disc in 1949, the record industry entered a "battle of the speeds." Under pressure to cope with the new formats, EQ curve unification was put on the back burner.

Priority of the magnetic tape standard (around 1949). Magnetic tape recording was rapidly gaining popularity among broadcasters, and developing a tape standard was the top priority in the 1949 NAB revision. The disc recording curves were left unchanged from the 1942 version.

The committee's democratic process. Whether NAB or RIAA, standardization was a democratic process that had to reconcile the interests of various companies. Reaching consensus among all parties took time. On the other hand, this democratic process ultimately produced a standard that the entire industry could accept.

→ What was the battle of the speeds?

→ How the NAB standard was developed — blog post Pt.8

Why RIAA "won"

The establishment of the RIAA curve itself is important, but there were technical and economic factors behind its adoption as the industry standard. This is covered in detail on a separate page.

→ Why did RIAA become the standard?

Related pages

• → What is the RIAA curve? — definition and time constants
• → What curves existed before RIAA? — list of major pre-RIAA curves
• → In a Nutshell: from the postwar period to the birth of the RIAA curve — a quick overview of the whole process

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