Subwoofer Reviews

Velodyne ULD-18 subwoofer system: Down-firing, floor-standing, dynamic, sealed-box, self-powered subwoofer with separate electronic crossover and servo-controlled power amplifier system. Driver: one 18" cone, ¾" linear travel, with accelerometer and preamp. Nominal input impedance: 20k ohms. Amplifier power: 400W continuous. Input sensitivity: 300mV for maximum output. Crossover: Independently selectable high-pass (36–212Hz), low-pass (60–193Hz) frequencies and phase (0 or 180° phase) via changing soldered-in resistors on a plug-in seven-terminal "header" socket by dealer. High-pass slopes (6–12dB/octave) can be also set. Unit under test shipped with nominal, standard 12dB/octave high-pass slope and both high- and low-pass frequency set at 85Hz. 15Hz subsonic filter point used with the 85Hz crossover. Frequency response: 18Hz–85Hz, ±3dB; 104dB at 20Hz with less than 0.5% THD.
Dimensions: "remote" power servo control unit: 17" W by 3.5" L by 11" D. Weight: 15 lbs.
Cabinet dimensions: 23.5" W by 31" L by 21.75" LH, 5.77 cubic feet. Weight: 105 lbs.
Finishes: walnut, oak, black; beveled hardwood edges, hardwood legs with concealed rollers.
Price: $2595 (1989); no longer available (2010).

Velodyne ULD-15 subwoofer system. Similar system using 15" cone, 5/8" linear travel. Frequency response: 18Hz–85Hz, ±3dB, 104dB at 20Hz with less than 1% THD.
Cabinet dimensions: 17" W by 22.5" L by 18.25" H, 2.59 cubic feet. Weight: 57 lbs.
Price: $1795 (1989); no longer available (2010).

Both: Warranty: 2 years, parts and labor. Approximate number of dealers: 240.
Manufacturer: Velodyne Acoustics, Inc., San Jose, CA 95112 (1989), 345 Digital Drive, Morgan Hill, CA 95037 (2010). Tel: (408) 465-2800. Fax: (408) 779-9208. Web: www.velodyne.com .