As in amateur boxing, this is the third and final round of the Subwoofer Comparison Test. This time we feature four speakers in the highest price category, $499 and up. No knock-outs or TKOs but certainly there are winners in our series of tests. But you are the judges and make the final determination. In the end, context is king. The woofer that is best is the one that is best for you.
Four Max Performance Long Excursion 12" WoofersIn the first round of the Subwoofer Comparison test we looked at four woofers that had price tags from $270-$300, followed by the second group that ranged from $309-$499. This month's selection includes four woofers with prices from $499-$799. These "heavyweights" (all of these woofers weigh between 29-38 lbs. each!) include the Crystal Mobile Sound CMPx212, the Fujitsu Ten Eclipse 88120Ti, the Kove Audio Armageddon Z-12 and the Massive Audio DMx12.
Like the previous sets of woofers I have examined, this group has some qualifications. First, the price spread for this lineup is about $300. Both the Kove and Massive woofers are priced the same $699 and $799 for the Eclipse, with the CMPx212 coming in at a mere $499. Despite this much difference, performance was fairly similar for all the woofers regardless of price. Like the first group, three of the woofers submitted have dual voice coils and one woofer with a single coil. This isn't really a problem as long as you keep in mind that the big difference between dual and single voice coil woofers is that it takes less voltage to drive a lower impedance dual voice coil woofer (when driven in parallel) to the same SPL levels as a higher impedance single voice coil woofer.
The other similarity worth noting is that all the woofers have rather low Vas numbers, which means they are capable of working into very small enclosures. However, two of the manufacturers recommend sealed and vented boxes (Kove recommends ported, Eclipse, sealed; more on that later) that were much larger than the numbers would indicate. The reason for this is that woofers in this category have tremendous power handling capabilities and are pretty much expected to be played at very high SPL levels (hey, no one is going to spend $700 on a subwoofer to play elevator music while cruising). At high SPL's the voice coils get very hot and the impedance increases to the point where the parameters are then more suitable for the larger box. In terms of vented boxes, it's almost impossible to create a vent for a small vented box that will move enough air to be satisfactory, so if you want performance, it's a larger box or nothing.
Testing was done using the same procedures as the previous subwoofer tests (this way you can compare results from review to review). The LinearX LMS analyzer (with the Win9X software) was used in conjunction with the LinearX VIBox to produce separate voltage and current curves (also called admittance curves) in a 10 Hz-10 kHz frequency range with a 550-point sweep resolution. Using "Ohms Law," these two curves were then mathematically divided (V/I=Z) and the data converted from voltage to Ohms to produce high-resolution impedance curves. This data was then imported into the LinearX LEAP CAD program (a Win9X version of LEAP is due out in a few months). Once the LMS data was loaded into the LEAP software, box simulations were created at 2.83V and at a voltage level high enough to produce cone excursion that was equal to the Xmax of the voice coil plus about 15%. This method describes the woofer's linear operating envelope, which approximates how loud the woofer will get before it starts creating noticeable distortion.