The Andromeda III speaker system was designed by Bob Carver in 1976. It was a 4-way system consisting of two flat panels, a sub-woofer and a Motion Control Module (active equalizer). The "Spatial Imaging" circuit was simply the Ambience circuit borrowed from the 2000 preamp.

The panels had front and rear facing mid-range drivers and upward facing tweeters with dispersion cones giving outstanding dispersion. They were very inefficient however (88 dB SPL, 1 watt-1meter). Suggested list price was $1349. Due to a dispute over the Andromeda name they were later re-named Phase III.

The MCM was redesigned several times early on. The pre-serial # 1736 schematic in the service manual only documents the final revision. No early schematics were published.

At serial # 1736 the speakers and MCM went through a major redesign. One of the tweeters was replaced by a 1" Philips soft dome, the crossover was revised as was the MCM resulting in a 5-way system.

At serial #1978 the Philips tweeter was replaced by a Polydax 1" soft dome which isn't documented in the schematic.

Trouble points:
1. The woofers face down with heavy cardboard rings glued to the dust cap causing the cones to fatigue over time resulting in lower output and higher distortion. They can be reconed.
2. The 8" mids were given added mass in the form of rope calk around the dust cap. The caulk soaked into the cone causing it to separate from the voice coil. They can be reconed with a butyl rubber surround.
3. The coil on the 8" drivers (above #1736) can melt at sustained high power.
4. 2.5 A panel fuses in the early version blew too easily and should be replaced with an AGC 4 A. Sub woofer fuses remained AGC 4 A throughout.
5. There is a misprint in the factory service manual MCM schematics. The one marked "#1736 and earlier" on page 10 should be #1736 and later.

OEM Drivers:
Check with companies like Parts Express and Madisound for replacements (on the web). Some are still available.

12" woofer CTS 12G24710 4 ohm

8" lower mid CTS 8E6840 8 ohm

4" upper mid Peerless K040MRF 8 ohm

1" cone Peerless MT20HFC 8 ohm

1" soft dome Philips 0165T8 8 ohm

1" soft dome Polydax HD12X9D25A 8 ohm

OEM coils:
Air core coils were custom wound at Phase Linear. Close replacements are available commercially. When substituting, match both sides.

Subwoofer 10 mH iron core (same value in early and later versions)

#1735 and earlier:

8" 4.0 mH iron core and .12 mH air core

1" cone .12 mH air core

#1736 and later:

8" 4.22 mH air core (the one that melts) - 460 turns #22 wire

4" 1.65 mH air core - 245 turns #18 wire

1" soft dome .22 mH air core - 140 turns #22 wire