SONY APM-77W (1981)

29 January 2024

SONY APM-77W (1981)

Brand: SONY

Model: APM-77W

Year: 1981

The highlight of the Sony APM-77W is the use of flat drivers, the so called APM (Accurate Pistonic Motion) driver which is a Sony development. The diaphragm of the woofer uses a honeycomb sandwich structure in which an aluminum core is sandwiched by aluminum skins, and a damper is incorporated in the sandwich structure to suppress plate vibration. This diaphragm is driven at four points by four magnetic circuits and a voice coil. This solution is a 100 times more rigid structure than a regular paper cone and it offers a clear, precise and even dispersion of sound. The midrange and tweeter use similar construction while the crossover is composed of 3-individual network boards.

Technical Data:

3-Way Bass Reflex

Max. Input: 200 W

Rated input: 100 W

Frequency Range: 28Hz-30.000Hz

Impedance: 6ohm

Woofer: 530 cm2 APM

Midrange: 27 cm2 APM

Tweeter: 7 cm2 APM

Dimensions: 405x745x325mm (WxHxD)

Weight: 32kg

Available also in grey color.