Installation
I got a hold of Steve Turrisi, JL Audio's Area Technical Director, to ask him what his thoughts were on the set up and enclosure recommendations for the best sound quality when using the 12W6v2-D4. He told me to use a sealed enclosure of 1.25ft3, and to hold onto my hindside because this subwoofer was going to shake it off. At the time, I was thinking that was a pretty bold statement for a technical wonk to make, but after testing I was definitely converted to Steve's way of thinking. But I am getting ahead of myself.
The 12W6v2-D4 has dual 4-ohm voice coils. JL Audio has helped make the hook up of the dual voice coils easier by having both voice coil hook-ups on the same side of the basket and by using four voice coil configuration tab terminals. These are located behind the main input connectors and are used to interconnect the dual voice coils in one of two ways: either in a series connection at an 8-ohm nominal impedance or a parallel connection with a 2-ohm nominal impedance. I went ahead with the factory configuration of a paralleled 2-ohms and my guys at Speaker Works busted out a 1.25ft3 sealed enclosure for the 12W6v2-D4.
Once I got the sub into its enclosure, I headed out to my Scorched-Earth Black Ford F-350 truck to finish up the installation and set up the listening test. I found that the 12W6v2 worked best with the enclosure on the floor of the cab between the front and back seat, with the subwoofer facing the rear of the cab.
To power the second generation W6, I installed a Zapco C2K-9.0XD amplifier. The 9.0XD features a 24dB-per-octave crossover and will pump out a throbbing 2000 watts of power at 2 ohms mono. The front half of my speaker system consists of a pair of USD Audio B-62 WaveGuide separates. I am powering these with a Zapco Competition C2K-6.0X amplifier at 150 watts per channel. The built-in high-pass crossover filter was used to block the bass to the component system. These amps are fed via Zapco's Symbilink balanced line driver SLB-U. There are no other signal processors in the signal path.
Listening
To open the testing, I inserted the Fine Young Cannibals' The Raw & The Cooked album into my head unit. I like this album because it is well recorded and was mastered for duplication by a friend of mine, Ellen Threatt-Smith. She has a fantastic pair of ears and a brilliant mind. I learned a ton about sound just by listening to her talk about it.
In "As Hard As It Is," the bass line opens with the bass guitar pumping out eight notes per bar, with the kick drum alternating between a single strike and double strikes at the first beat of each bar. The bass guitar is tight and clear and the kick drum hits hard with a ton of impact and no hangover, but the kick drum is not all that audible. Note shifts are clearly audible in the bass guitar and the imaging is fantastic. All of the subwoofer information images completely up front with nothing pulling the image to the rear.
Moving to a new piece of music, I popped in Steven Curtis Chapman's album Speechless, track 11, "With Hope." Again the 12W6v2-D4 has no trouble keeping the image of the bass guitar up in the front of the soundstage. This demonstrates how successful the JL Audio engineers have been in controlling harmonic distortion. The bass guitar notes are forceful and tight. Note shifts are clear with no blooming in the upper bass frequencies like a number of the other subwoofers that I have tested in the past. The detail in the bass line is great. The 12W6v2-D4 has got to be the most linear subwoofer in frequency response that I have tested.