Vintage Recording Equipment Archive

Introduced in 1976, the Crown EQ 2 Graphic Equaliser combined two channels of eleven-band equalisation with independently adjustable bass and treble shelving controls. Each equaliser band offered stepped boost and cut together with a variable centre frequency, allowing adjustments between the nominal octave centres. Its combination of broad tonal adjustment and more selective frequency correction formed Crown’s synergistic equalisation system, intended to compensate for response irregularities in audio equipment, room acoustics and recorded material.

The Langevin EQ-252-A was a seven-band passive graphic equaliser designed for recording, television broadcasting and motion-picture sound. It combined individual sliding controls with fixed frequency bands, providing up to 8 dB of boost or attenuation in 1 dB steps. Its bridged-T circuitry required no valves or power supply, while seven plug-in filter sections, sealed toroidal coils and gold-plated switching contacts formed a compact assembly intended for panel mounting.