A 2.5-way centre speaker from the Motion Foundation series: a Folded Motion S tweeter and two 14 cm aluminium woofers in a compact cabinet, designed to give a home cinema system clear dialogue.
Foundation C1: the centre channel design
The Foundation C1 completes the front stage of a multichannel system built around Motion Foundation speakers. Most of the dialogue in a film is carried by the centre channel, which is why the design concentrates on the intelligibility of voices. Stated response is 53 Hz to 23 kHz within ±3 dB, with 91 dB sensitivity and a 4 ohm impedance; the recommended amplifier is rated somewhere between 15 and 100 watts.
The two 14 cm woofers, with Unibody aluminium cones and stamped steel baskets, are wired in a 2.5-way arrangement that MartinLogan calls Anti-Lobing and also uses in its C100 and C10 centres; the crossover frequencies are 2,900 Hz and 3,200 Hz. The aim is to remove lobing and keep the tonal character of the original material; according to the maker this gives the performance of a larger three-way in a speaker that fits more easily among the furniture.
High frequencies go to the 24 x 25 mm Folded Motion S Gen2 Obsidian tweeter, with a 22.6 cm² folded-film diaphragm, the same unit found in every model of the series. Its waveguide sets dispersion at 90° horizontally and vertically, so voices stay clear right across the seating area. The cabinet is a bass reflex design with a rear port, and the five-way binding posts are for single wiring.
Specifications
- Type: 2.5-way centre speaker, rear-ported
- Frequency range: 53 Hz to 23 kHz, ±3 dB
- Impedance: 4 ohms
- Sensitivity: 91 dB
- Amplifier power: 15 to 100 W
- Crossover points: 2,900 Hz and 3,200 Hz
- Tweeter: 24 x 25 mm Folded Motion S Gen2, 22.6 cm² diaphragm
- Tweeter coverage: 90° horizontal, 90° vertical
- Woofers: two 14 cm Unibody aluminium cones, steel baskets
- Cabinet: bass reflex, port at the rear
- Terminals: five-way posts, single-wire only
- Grille: magnetic cloth grille over the woofers
- Supplied: sold singly
- Finishes: black, white, walnut
