Sony apm-22es (1984–1989)

Name: Sony apm-22es
Brand: Sony

A 2-way bookshelf speaker system using Sony's APM planar drivers, released in Japan in 1984 and later in Europe and Australia.

Overview

The Sony APM-22ES is a 2-way, 2-speaker, bass reflex system of bookshelf type, featuring Sony's proprietary APM (Air Pressure Modulation) planar drivers. Originally released in Japan in 1984, it was later made available in Europe and Australia in 1987 as the APM-22ES MKII, which came in an all-black finish with a big-magnet dome tweeter. The original model was also offered in black (APM-22ESB) and wood-grain finishes. It was recognized as a HiFi Choice Best Buy in the UK, with users frequently describing its sound as "great," "excellent," or "seriously good sounding," though some preferred the smaller APM-12ES.

Specifications

Product type	2-way, 2-speaker, bass reflex system, bookshelf type speaker system
Playback frequency band	38 Hz to 30000 Hz
Output sound pressure level	90dB/W/m
Impedance	6 Ω
Rated input level	60W
Maximum instantaneous input level	120W
Crossover frequency	1.3kHz
Woofer size/type	290 cm² Plane type
Tweeter size/type	16 cm² Plane type
Tweeter level control	Can be controlled from 0 dB to -50dB
External dimensions	Width 310 x Height 515 x Depth 310 mm
Weight	15kg
Original price	¥39,000 (for 1 unit, around 1984)

Design

The APM-22ES employs APM (Air Pressure Modulation) units. The woofer uses an APM type design with an aluminum honeycomb vibration plate driven at multiple points by four armatures directly connected to the voice coil, allowing divided vibration to be effectively canceled and expanding the piston motion band. The tweeter is also an APM type, using a light and strong aluminum honeycomb vibrating plate driven by a large voice coil at the node points of divided vibration, eliminating such vibration within the audible range. The enclosure features an acoustic rounded design with R-shaped corners to prevent diffraction and was available in black wood-grain and walnut finishes. The 1985 APM-22ESAV model uses the same drivers but is slightly narrower and includes a ferrite plug over the drivers to avoid interference with CRT televisions placed between them.

Context

The APM-22ES was available in two versions, with the US model directly equivalent to the original Japanese version. It was named a HiFi Choice Best Buy in the UK, reflecting its strong reception in the high-fidelity market.

Market

Multiple users report failing tweeters, and Sony no longer supplies official replacements. Failed tweeters can sometimes be repaired if the voice coil remains undamaged. Second-hand prices have historically been low, with forum reports of £10–£15 per pair in the 2000s and one offer around US$150.