IEC 60651:1979/AMD1:1993 ed1.0

Заменен

Amendment 1 - Sound level meters — 15 стр.

Contains changes to the clauses of IEC 651 and a new appendix D with equations for design-goal frequency weightings.

Заменен на

IEC 61672-1:2002 ed1.0

ICS

17.140.50 Electroacoustics. Including sound level meters / Электроакустика. Включая слуховые аппараты и шумомеры