IEC 60098: Analogue Audio Disc Records — The Standardization of Vinyl

The RIAA Curve: How a 1954 Standard Still Defines Vinyl Sound Quality in 2026

IEC 60098 specifies analogue audio disc record parameters. Its most important contribution to audio engineering is the RIAA equalization curve — bass reduced and treble boosted during cutting, reversed during playback.

Why equalization is necessary: A vinyl groove amplitude at low frequencies would be too large (adjacent grooves would collide); at high frequencies it would be too small (drowned by surface noise). The RIAA curve solves this physical contradiction: bass attenuated ~20 dB during recording, treble boosted ~20 dB — on playback, the reverse restores the original frequency response while compressing surface noise (predominantly high-frequency) by about 20 dB.

Three time constants: 50 Hz (bass cut-in), 500 Hz (midrange reference), 2,122 Hz (treble boost start). Every phono preamplifier must precisely invert these three breakpoints — any deviation alters the musical frequency balance. A 1954 standard, still executed with precision in every phono stage manufactured today.

TN Lab — The RIAA curve defined in 1954 is still precisely executed in every phono preamplifier built today.