| Form Factor | Floorstanding |
| Signal Path | Passive Hardware |
| Super Tweeter | 3"x6" Electrostatic Panel (x5) (RTR HF-50) |
| Treble/Midrange | Electrostatic (Quad ESL-57) |
| Bass | 210mmx300mm Foil-stressed Expanded Plastic Flat Diaphragm (KEF B139 SP1044) |
| Crossover | Active |
| Enclosure Type | Midrange/Treble: Dipole, Bass: Transmission Line |
| Finish | Walnut (Optional: Rosewood) |
| MSRP (1971) | $1200 (MSRP (1971, Basic Kit): $150) |
| Notes | Full-range speaker system designed around a core composed of the Quad ESL-57. System consists of two units per channel with Quad ESL-57 and tweeters in one and the bass driver separately located in a transmission line loaded tower. A special ESS brand electronic crossover completed the system. Sold as various options from basic plans/kit to everything including the Quad speakers with a middle option of everything but the Quads. |
