Description
James Loudspeaker ST Series ST21-4 21 Inch 4 ohm and 70V Subterranean Subwoofer
The ST21-4, a 21″ subterranean subwoofer was developed for high SPL bass output outdoor applications. It features a powerful 21″ transducer for maximum excursion and SPL. The ST21-4 can be directly driven by an M1000 subwoofer amp which produces 70V of output, or 1000W+ at the 4ohm rating. However, at 1000W, wire loss needs to be considered and calculated as with any other 4 ohm wire run. In all applications, the ST21-4should be bi-amped.
Also, the ST21-4 is quite heavy. Four eyebolts are located on the top to allow the subwoofer to be lowered into the ground.
Specifications
18-120Hz +/-3dB
4 ohms
91dB 2.83V/1m
500 – 1000W
M1000
(1) 21″ (534mm) Aluminum
Aircraft Marine Grade Aluminum
Black buried enclosure and black exposed port, custom finishes available for a nominal upcharge
24 in (609.60 mm)
24 in (609.60 mm)
24 in (609.60 mm)
