JL Audio Fathom f112 Subwoofer


Let's get to it.

The Fathom f112 subwoofer is a freaking rock of build quality, evidenced not only in finish, and the fit of components, but sheer weight, most of which resides in the absolutely massive motor assembly of the driver. With heaps of switching amplifier power and lots of power handling, the subwoofer doesn't require a whole lot of enclosure volume to get deep, prodigious bass. It's not the smallest subwoofer, to be sure, but for its low frequency output capabilities, particularly with a simple sealed system, the unit is downright tiny. Tiny, but not light. Between carrying them up the stairs, unpacking, and moving these things around for optimal room location, I just about broke myself. If you take these things home, don't let pride break you. Bring a friend, and better yet, a piano dolly with that willing companion. Got stairs? Good luck. And by the way, I keep saying subwoofer(s) because I got two of them for this review.

Something I found really interesting was the fact that the Fathom "12 inch" driver, unlike most other drivers actually was a whole 12" from edge to edge of the surround. This shouldn't be atypical, but it is. Most drivers called 12" in diameters, are 12", sort of, but not if you only include the parts that actually push air. Many just have a 12" frame, and the cone/surround are actually substantially smaller. Now, as most DIY bass enthusiasts will tell you, you don't count edge to edge if you want to calculate the radiating area, but rather from the middle of the surround on one side to the middle of the surround on the other side. The surrounds on the Fathom f112 drivers are big and fat to accommodate long excursions, so the radiating area, for the sake of doing displacement calculations, has a diameter of roughly 10.5". Still, that doesn't negate the fact that this is a beefy 12" driver, with a real 12", and when combined with the massively long throw, more potent, in terms of displacement, bigger than every other I've seen claim the 12" specification.

This machine isn't just pretty on the outside. While I liked that the driver extends the surround to the actual edge of the frame of the basket, hiding anything ugly, it's also pretty on the inside. The motor structure if just plain massive, giving you plenty of power handling (and inversely less power compression), and the switching power amplifier section makes full use of that capacity. I couldn't figure out an easy way to remove the driver to take a look at it, and having seen how difficult it is to maneuver a driver that heavy, didn't want to really find out. Instead, I show you this image from our 2006 CEDIA show report, detailing the driver assembly (photo below). The driver sports over 2" peak to peak linear excursion, with 4" peak to peak total excursion.

The amplifier and driver are matched, both in terms of power output, and impedance, providing some really ridiculous low frequency output capabilities for a single driver subwoofer of this physical size.


So, yeah, it's technically impressive.

The bread and butter question though, is how does it sound? I think I've hinted at that, previously, but let me clarify.

The Fathom f112s sound AWESOME!

By that I mean . . . .

As Arny Krueger has said, "A perfect loudspeaker is an oxymoron". Some compromise is inherent in anything. Every loudspeaker system, of any type (especially those highly polished $250,000/pr monoliths), have weaknesses. The art of and science of loudspeaker design is to balance, work around, and avoid compromise within the constraints of size, budget, and physics, to achieve the best performance within a set of target goals. In my opinion, the JL Audio Fathom f112 is one of the most elegant expressions of combining art, engineering, and just plain sense in the a price range that, while not cheap, is entirely within the range of mortal budgets. Not everybody's budget, but a brand new f112 still costs less than a reasonably good used motorcycle. For the cost of a pair, you could buy a fairly decent new motorcycle. Still, for somebody who loves audio, I'd consider the a pair of Fathom f112 subwoofers a far greater value.


I believe that if an audio system can't do music well, it can't really do theater audio. And, if it can't do the dynamics of theater, it's dead in the water for music. Sound is sound, by definition. Music is in movies. Voices are in music. Percussion is in both. It's just a fact. If a person has a preference/tolerance for certain colorations under different playback scenarios, that's their right. But, for me, if it can't do both well, it doesn't do either well.

I really like films, and am absolutely spoiled by good video, but when it comes to being critical, I am a music lover first. It is in the context of listening to music that I REALLY pay attention to the audio, because that's the only thing of consequence. Rendering music, the Fathom f112s did so absolutely wonderfully, and I just plain fell in love.