Sony SS-G777ES (1988–1991)

A high-end 3-way bookshelf speaker system built with exotic materials and precision engineering, from Sony's pre-1991 commitment to natural sound reproduction.

Overview

The Sony SS-G777ES is a 3-way bass-reflex loudspeaker system developed between 1988 and 1991 as part of Sony's ES (Elevated Standard) series. It was marketed as a speaker into which "all of Sony's technology and know-how" was invested, and it was designed for realistic, natural sound reproduction. It was described as "Sony's penultimate high-end loudspeaker" - and still the company provided no advertising for it. That added to the misconception that Sony did not produce serious high-end audio equipment. The system uses a bi-wired design concept with separate networks for high and low frequencies. It was sold with optional WS-777 stands.

Specifications

Type	3-way bass-reflex
Drivers	1x 30 cm bass cone, 1x 6.5 cm dome midrange, 1x 2.5 cm ceramic dome tweeter
Frequency response	25 Hz to 50000 Hz
Sensitivity	89dB/W/m
Impedance	6 Ω
Max. input power	100W
Max peak power	200W
Crossover frequency	450 Hz, 5500 Hz
Dimensions	Width 430 x Height 740 x Depth 360 mm
Weight	47kg
Input terminals	bi-wiring

Design

The SS-G777ES uses advanced materials throughout. The bass driver has a unidirectional carbon fiber cone with a slightly exponential shape and an Alnico oxygen-free copper magnetic circuit, mounted in a heavy 4.2 kg aluminum die-cast frame. The midrange and tweeter use 99.9999% pure silicon carbide (SiC) fine ceramic diaphragms, vapor-deposited for precision. All drivers employ Alnico magnets. The crossover network uses European-sourced air-core coils and metalized polypropylene capacitors, with separate filtered circuits for high and low frequencies to prevent back-current interference. The enclosure is laminated beech and birch wood, 4 cm thick, finished in real rosewood, with vibration-damping polyurethane washers and felt-rubber-damped screws at the bass driver. The baffle uses specially laminated plywood, and each component connection is solder-free.

Context

Sony pursued high-end sound with this speaker without advertising it.

Market

Original pricing was ¥200,000 per unit in 1988, with a later listing at ¥185,600 in 1991. The optional WS-777 stands measured 43 x 25 x 32 cm and sold for ¥60,000. Production is estimated at fewer than 1,000 pairs. One noted issue is susceptibility to water damage in the wood cabinet, which requires restoration. A 2019 listing appeared at PLN 30,000. A potential buyer questioned if $500 was a fair price, and another user suggested it "sounds a little high."

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