When did major U.S. labels move to the RIAA curve — a list based on verifiable documents

Last updated: April 14, 2026 Reading time: approx. 6 min

When did each label switch to the RIAA curve?

Question answered on this page: When did the major U.S. labels complete the transition to RIAA recording characteristics?

Background: the transition did not happen overnight

The RIAA standard was established in January 1954, but labels did not all switch the next day. There were two main reasons the transition took time.

Existing inventory: Pressings from stampers cut with the old curves remained in stock and continued to circulate in the market.
Cost of equipment updates: Cutting equalizers had fixed characteristics, and updating equipment at all facilities was costly and time-consuming. Measurement and fine-tuning through test cutting was also necessary.

Also, RCA Victor and Capitol had been using recording characteristics identical to RIAA before the standard was established, so they required no "transition" at all.

Transition timeline for major labels

The following list is based on information verified from primary sources (trade journal articles, engineer testimonies, internal documents, etc.).

Label	Transition period	Basis
RCA Victor	From around 1952 (no transition needed)	New Orthophonic recording characteristics = identical to RIAA. Adopted around 1952
Capitol	From around summer 1953 (adopted identical characteristics before RIAA was established)	Switched from old AES curve to New Orthophonic = RIAA. Estimated to have been completed during 1954
Columbia	Less than half transitioned as of August 1954. Estimated completion in early 1955, late 1955 at the latest	Billboard, August 1954: "All facilities still six months away from completing transition." Bachman internal documents (c. 1955–1956) also support this timeline
Mercury	Around 1954	Chief engineer C. Robert Fine announced intention to adopt RIAA (Radio & Television News, July 1954). The earliest LPs (cut at Reeves Sound Studios around 1949) are estimated to have used NAB or Columbia LP curves, shifting to AES around 1951–1952
London (UK Decca)	Early 1954	A&R director Remy van Wyck Farkas: "We have been using RIAA for several months" (High Fidelity, June 1954)
U.S. Decca	Around 1955 (relatively late)	Transitioned from NAB curve. Some sources suggest NAB was used until around November 1955
MGM	Around late 1954 (details unknown)	Pre-transition curve likely 500N-12 (Old Orthophonic turnover/bass shelf + AES HF rolloff), though accounts vary. Most sources suggest the transition was completed in late 1954
Westminster	Same as Columbia	Sent tapes to Columbia for cutting and pressing. Transition followed Columbia's timeline. However, some were sent to RCA Victor for cutting and pressing. These would have been cut using Old Orthophonic or New Orthophonic, yet the jacket indicates playback with the AES curve

CSL (Columbia Standard Level) — Label face of a Columbia Records test pressing, CSL (Columbia Standard Level, SIDE II, ZRD 431-1A). It explicitly reads "COLUMBIA STANDARD CHARACTERISTIC as per R.I.A.A. — N.A.R.T.B. industry norm," Columbia's own official declaration of conformity to the RIAA / NARTB standard (from the author's collection)

Independent studios

Studio / Engineer	Major client labels	Transition period	Basis
Rudy Van Gelder	Blue Note, Prestige, Impulse!, etc.	Early 1955	Introduced RIAA recording equipment (Gotham PFB-150WA) in early 1955. Stated his own use of RIAA in an article he contributed in October 1955
Capitol-commissioned independents	Contemporary, Good Time Jazz, etc.	From around fall 1953	Used Capitol's cutting facilities, so their transition followed Capitol's
Columbia-commissioned independents	Various	Same as Columbia	Used Columbia's cutting facilities
RCA Victor-commissioned independents	Various	From around 1952	Used RCA Victor's cutting facilities

1958: effectively complete with stereo LPs

When the stereo LP was introduced in 1958, cutting equipment was designed with RIAA as the standard, leaving no room for any curve other than RIAA in stereo LP production.

→ Are all U.S. stereo LPs on the RIAA curve?

Supplement: corroboration from test records

Professional frequency-response test records also support the RIAA transition.

Before the RIAA standard was established, test records existed that were cut with various curves, including NAB, ffrr, and Columbia LP curves.

The Measure of Your Phonograph's Equalization (Dubbings D-101, 1953) — Back cover of Dubbings Company D-101, "The Measure of Your Phonograph's Equalization" (1953). Apparently intended for audio dealers and repair shops to check phono equalizers in playback equipment. It contains the same tone signals cut in four different curves — Columbia LP / New Orthophonic / NARTB (1949 NAB) / AES — a striking illustration of the multi-curve situation of the time (from the author's collection)

However, by the time the stereo LP was introduced, only test records cut with the RIAA curve (or RIAA with the high-frequency pre-emphasis removed) have been identified.

The Equalization of Reproducers (Columbia SF-1) — From the booklet of Columbia SF-1, "Listening in Depth: An Introduction to Columbia Stereophonic Sound" (c. 1958). An explanatory page on RIAA recording/playback characteristics by William S. Bachman (one of the members who formulated the RIAA standard, and chief engineer at Columbia). It also shows a correction circuit to compensate for the playback error of ceramic cartridges. This documents Columbia itself publicly identifying RIAA as the industry standard at the time of the stereo LP's introduction (from the author's collection)

For details → Pt.21

(→ Is there a reliable EQ curve reference? — overview of documentation including test records)

Supplement: how to read this table

This table is based on primary sources the author has been able to verify. It does not cover all labels and all pressings.

In particular, some smaller independent studios may have continued to use old equipment due to lack of funds. Records of such cases were often not kept, and the exact transition dates are unknown.

Also, some independent labels in the monaural era outsourced to multiple mastering and pressing plants simultaneously. Some cut their own masters and outsourced only pressing; others sent tapes and outsourced both cutting and pressing. These varied arrangements make the full picture even harder to reconstruct. As a result, even records with the same label and catalog number may have been cut with different curves depending on the pressing.

For details → Pt.20

← Back to FAQ

Revision History

April 14, 2026: Added figures
April 8, 2026: Initial publication