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Velodyne Digital Drive Plus Subwoofers: DD-10+, DD-12+, DD-15+, DD-18+

by Nyal Mellor February 16, 2011

Velodyne announced their replacement for their premium Digital Drive subwoofer line towards the tail end of last year. The original Digital Drive subwoofers are now getting a bit long in the tooth and with the recent barnstorming entrance of JL Audio into the home subwoofer market an update was definitely required. />

The new line is rather creatively called the Digital Drive Plus line. They are keeping the same model range based on drive unit sizing and offer the 10

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The new line is rather creatively called the Digital Drive Plus line. They are keeping the same model range based on drive unit sizing and offer the 10

One of the best things about the Digital Drive line is the ability to measure your room and set up equalization filters to counteract peaks in the frequency response due to room modes. The old Digital Drive line required hooking up the subwoofer to a TV set in order to view and set up the equalization. Whilst this was ok in a home theater type situation it did prove challenging for two channel setups where no TV was nearby! The new Digital Drive plus line allows the calibrator to setup correction filters using a new PC program (Windows only unfortunately) as well as being able to hook up to a TV as in the older version. /><img src=

manually work with EQ filters is one of our four key functional criteria that all room correction products must have. Many manufacturers (JL Audio included) only include an automatic EQ mode and do not allow the calibrator to adjust any EQ filters that are generated by the optimization process. Whilst this works well for getting a basic setup I have always got better results setting up EQ filters completely by hand.

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I am very interested by Velodyne's claims of <1% distortion. They have obviously put a lot of work into their new subwoofers and in particular their new subwoofer drivers which incorporate huge magnet structures and 6mm thick multi-layer rohacell cones.

We humans do not perceive even moderately high levels of distortion (say 5%) in the reproduction of a fundamental note at 20Hz or 40Hz. This is often quoted as being an excuse for having subwoofers with high distortion. The problem is that we do perceive the harmonics of a highly distorted 20Hz bass up into the midrange where we are much more sensitive to distortion. This is the key reason to have low distortion bass reproduction. High quality subwoofers such as the Velodyne Digital Drive or JL Audio F-line nearly always have lower distortion than most expensive speakers which often quote distortion measurements in the low bass frequencies of 2 or 3%.

<strong>Want more information on the Velodyne Digital Drive series or need help choosing a subwoofer for your home theater or listening room? <a href=

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About the author: Nyal Mellor is founder of Acoustic Frontiers, a company specializing in the design, build and calibration of high performance home theaters for enthusiasts worldwide.

Nyal Mellor

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Also in Low Frequency Optimization

JL Audio show the E112 - a new lower cost 12" subwoofer - at CES

by Nyal Mellor January 22, 2012 0 Comments

JL Audio, the manufacturer of the superb Fathom F110, F112, F113, F212 and Gotham subwoofers showed their new E112 subwoofer at CES. I have seen this sub before, at CI Expo, a custom integrator event that was held in Berkeley this year. But this is the first time I had my camera with me to take some photos!

Subwoofer setup and integration 101: sub crossover frequency, slope and phase for two channel systems

by Nyal Mellor October 11, 2011 0 Comments

Two channel amplifiers with bass management and room correction!

by Nyal Mellor May 13, 2011 0 Comments

Recently I have become aware of a new class of product: two channel amplifiers WITH bass management AND room correction. Why is this cool? Well until this new class of products came out the only way to do this type of thing was with a home theater receiver or a separate preamplifier such as a DEQX or TacT and a power amplifier. Two channel systems benefit just as much from subwoofers and equalization as home theater systems. Many two channel speakers, even high end ones, cannot reproduce low bass below say 30-40Hz with low distortion. A JL Audio F112 can play down to 19Hz at a -3dB point! Using subwoofers also allows for cunning room mode cancellation and avoidance of speaker boundary interference.