The vented box is larger and of course plays lower in frequency with an F3 of 29.6 Hz. It also takes more power to push it to its excursion limits. At 68V the simulation predicts 122.1 dB. As can be seen in the LEAP graph, damping changes appreciably at these voltage levels (LEAP uses non-linear models of BL and compliance plus dynamic changes in voice coil temperature to simulate this with a good degree of accuracy), but that's normal. This also explains why the smaller sealed box is probably more musical at almost any level as the changes in dynamic damping aren't as radical as it is with a vented design. Either way, your ears will be distorting before the JL 18W3.
Considering the outstanding performance and reputation for reliability that comes from JL Audio plus the enhanced thermal cooling capability, this new JL 18W3 woofer should be a hit with anyone who's got the space to use it. How does it sound with music? I think Mikey likes it. -V.D.
ListeningThis no-nonsense woofer has a look that says "strictly business." The design is all about function without flash. What you are paying for here is top-notch performance. Connections are handled with a pair of 0.187" faston terminals on each side of the basket, one set for each of the 2-ohm voice coils. I took advantage of these connectors and soldered the incoming wires for the lowest resistance, which you can't do with spring-loaded terminals. A tall gasket on top of the basket allows for inverted mounting, or even isobaric loading (two woofers in a push-pull configuration) without worrying about the surrounds colliding.
I used a sealed cabinet with a volume of 3.82 cubic ft., just under the manufacturer's recommended maximum size of 4 cubic ft.. This yielded a Qts of 0.762 according to LMS. The enclosure was built of 3/4" plywood with braces across the center to prevent the panels from resonating. No damping material was added.
I connected the two voice coils to the stereo outputs of an amp that produces 500 watts per channel into a 2-ohm load. The speaker is rated for 400 watts continuous power, leaving me with a decent amount of headroom for transients. I measured the maximum SPL output of this single driver at 125.8 dB, SPL, in the minivan. I set the crossover point to 100 Hz for the listening tests.
The first thing that came to mind when I began to listen was the word "smooth." No matter the type of music I played or the volume level, the woofer seemed to stand there with its arms crossed saying, "When are you going to give me a challenge?" It has excellent linearity, with no discernable difference between very low and very high volumes. On the title track of Radiohead's "Kid A" disc, there is a synthesized kick drum sound that has a very fast attack and decay which is great for checking for overhang. This speaker was more than fast enough to handle it with ease.
If you want accuracy and detail in combination with the ability to generate massive SPL, I doubt you will find a better choice than this. You will need a large box volume to take full advantage of the capability this 18 provides, but it's well worth it. -M.F.
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