User manual VELODYNE DF-10SC

[. . . ] ft. voice coil diameter WARNING! Do not power up system before consulting manual. Incorrect installation could result in damage to unit that will not be covered under warranty. Please follow these easy steps before using/installing unit. [. . . ] q Never expose the Servo-Controller housing to moisture. q DO NOT try to adjust the setup controls in control unit. Refer all adjustments to an authorized Velodyne dealer/installer. q If any part of your Velodyne Servo-Controlled subwoofer or controller should require service, return unit to your authorized dealer. There are no user serviceable parts inside. Velodyne Acoustics, Inc. Suite #101 San Jose, CA 95112 408. 436. 7270 voice 408. 436. 7276 fax 9 2 Servo Technology Velodyne pioneered the use of servo-control technology as a means of reducing distortion over a decade ago. Now, we are the first to offer this revolutionary technology for use in the automobile. In normal music listening, we are exposed to many forms of distortion. Every component in the signal path adds it's own characteristic distortion to the signal. Since most high quality electronics available now have distortion levels far lower than we are able to hear, that leaves your speakers as the worst offenders. While we scrutinize distortion specifications before we buy an electronic component, we rarely see anyone list distortion on loudspeakers. That is because traditional subwoofers (even high quality types) can produce distortion levels around 25% at typical levels. Even at only one watt input power, many subwoofers produce from 8-10% distortion. Traditional speakers produce sound by using a cone which is forced to move by an electromagnetic motor. The motor is connected directly to an amplifier, which provides the necessary increase in power to drive the speaker. If a speaker was functionally "perfect", this method would work fine. The problem arises when the fast moving speaker cone is called upon to stop & change direction quickly. The speaker cone may continue to move, resulting in muddy bass with an increased amount of harmonic distortion. [. . . ] Forcing the speaker's acoustical output into a true representation of the music. The term "servo" is misused by some manufacturers who use a different motor on their speakers to try and make woofers sound like larger more powerful units. Unfortunately this usually results in a large amount of distortion as well. [. . . ]