The 1176 Peak Limiter is a dynamic range compressor designed by the American engineer Bill Putnam and introduced by UREI in 1967. Derived from the 175 and 176 tube compressors, it marked the transition from vacuum tubes to solid-state technology.

The LA-2A Leveling Amplifier is an audio compressor produced by Teletronix Engineering Company from 1965 until 1969, and reissued in 2000 by Universal Audio.