Specs:
Size (h/w/d): 63.5 x 29.5 x 30.5 cm
Cabinet volume: 44 litres
Cabinet construction: Thin walled multiply, heavily bitumen damped and lined with acoustic foam. Reflex tuned with large offset ducted port.
Sensitivity: 87dB
Bass roll-off: 41Hz
Recommended amplifier power: 12-150 wpc
The SP-1 has three driver units but two of them are tweeters, so it more like a two-way than a conventional three-way speaker system. The 8” bass-mid driver is polypropylene and crosses over to the mid-tweeter at 3 kHz and then to the super-tweeter at 13 kHz
The tweeters are the Celestion HF 1300 and the Coles 4001G.