Reviews of Attainable Hi-Fi & Home-Theater Equipment

Reviews of Attainable Hi-Fi & Home-Theater Equipment

JL Audio Fathom f110Great BuyThose who have home theaters take the use of a subwoofer for granted. How else can you hear -- or feel -- dinosaur belches, exploding spaceships, and the other subsonic sound effects that make the home-theater experience so much fun? But doesn’t music, especially of the rock variety, also have lots of bass energy? And don’t many of the speakers found in two-channel systems (think two-way, stand-mounted speakers) lack the ability to pump out bass in the lowest octave (20-40Hz)? If so, a subwoofer would seem to be a logical addition to a two-channel audio system. But one seldom sees subwoofers in these environments.

You probably know why. Have you heard subs in music-only two-channel systems that, while pumping out lots of bass energy, just don’t sound as if they’re part of the rest of the system? Unfortunately, that’s often what happens with such a combination: lots of bass that’s not well integrated into the overall sound. Many audiophiles eventually choose to put up with a bass deficit rather than bass that sounds unnatural. I’ve been there, and wound up making the same choice.

But since I last tried using one in my system, subwoofers have improved. Could the use of computerized setup techniques, along with superior subwoofer technology, now let me succeed in integrating a sub into my system? I knew it would be hard; my primary speakers are Affirm Audio Luminations, whose lightning-fast Feastrex Monster alnico horn drivers reproduce music with extreme detail. But, as with most single-driver horn speakers, the Lumination’s bass starts to roll off below 50Hz, making it a perfect candidate for some sort of bass augmentation. I thought it would be worth another try.

JL Audio, maker of a wide variety of highly rated subwoofers, agreed, and sent me a pair.

Enter JL Audio . . .

JL Audio began as a manufacturer of audio gear for cars, and in 2004 expanded their line to include subwoofers for the home. Their first home sub, the Fathom f113, took the audio world by storm. It not only produced the deep, high-impact bass needed for a theater system, but also the fast, detailed, musical bass so often lacking when one tries to integrate a subwoofer into a music system. Understandably, the most intriguing models in the JLA line are the biggest, capable of wall-flexing output way below the lowest audible frequency (20Hz) -- who can blame reviewers for being seduced by them? But for audiophiles on more modest budgets (like me), JLA produces a baby model, the Fathom f110.

201005_jlsubdriverThe f110 has the same design as the rest of the subs in the Fathom line, scaled down to incorporate the 10” version of JLA’s massive W7 driver. That makes it, at 15.64”H x 12.92”W x 17.27”D, the smallest sub JLA makes. Its prices, too, are scaled back: $2100 USD in satin black, $2200 in high-gloss black. Although at 67 pounds the f110 is quite solid for its size, it won’t give you a hernia when you maneuver it into position. Having already had a hernia, I appreciate that.

When you add a subwoofer to a music system, you face two challenges: integrating the subwoofer into the room so it doesn’t excite standing waves, and integrating the outputs of your subwoofer and main speakers so the result sounds as if there’s a single speaker playing. Computers can help with both challenges. JLA subwoofers include Automatic Room Optimization (A.R.O.), a proprietary computer program that generates a series of tones that are picked up by a calibrated microphone (included). The software then adjusts the output of the subwoofer to best blend with the room, to minimize the most serious peak in the frequency response. Ideally, this gives the owner more flexibility in positioning the sub.

Part of the challenge in getting a subwoofer to work well with the main speakers may be the result of differences in speed of response. I’ve tried some cheap subs with my fast horns, and they didn’t blend at all well. No surprise there; those subs were designed for home-theater systems, where the quantity of output was more important than its quality. The Fathom f110, however, has a sealed enclosure to produce fast, clean bass. Its 900W amplifier and huge magnet should effortlessly move that 10” cone. Many subwoofers have ported enclosures, which can produce more volume but, arguably, not better sound.

The Fathom f110 doesn’t suffer from one of my pet subwoofer peeves: inaccessible controls. Its controls, including the A.R.O. settings, are on the front panel above the driver --- you don’t have to fumble around behind the sub or get down on all fours to make adjustments. You can connect the f110 to your system via unbalanced (RCA) or balanced (XLR) line-level connectors, but not via high-level connections to the terminals of your main speakers. If you want to drive a second f110 in parallel, an XLR output jack lets you connect the two together to be driven by the same signal. The crossover can be set at 12dB or 24dB per octave, or turned off so that the LFE output of a receiver or processor can control the slope. The cutoff frequency can be set anywhere from 30 to 130Hz, making the f110 suitable for use with just about any semi-full-range speaker imaginable.

One problem I had trying to get other subwoofers to work with my Luminations was that the horns are so sensitive, with such a high output, that the subs’ amps didn’t have enough gain to match it. To add gain, I had to insert a spare preamplifier between my linestage and the input to the subwoofer. But JLA claims that the f110’s gain is as much as 15dB above the reference gain (i.e., that of the main speakers), so I shouldn’t have to use the extra preamp.

Assuming its published specifications are accurate, the Fathom f110 isn’t compromised by its small size, with lower limits of 27Hz (-1.5dB), 25Hz (-3dB), and 19Hz (-10dB) -- not at all shabby for a baby sub. Many far larger subwoofers would kill for that kind of extension.

The f110s’ small cabinets (I was sent two units) were unobtrusive, and their mirror-gloss finish looked like glass. To my eye, they looked very elegant. They rest on four conical rubber feet that, while not penetrating my carpet, seemed effective at preventing the subs from wobbling or moving.

In addition to the On/Off positions, the f110’s power switch provides an Auto setting, which turns the subwoofer on when a signal is received, and off when there’s been no signal for about 30 minutes -- a lazy person’s dream. I like that.

In use

When you add a subwoofer to your system, you need a plan. Just what do you want the subwoofer to do for you: extend the deepest bass of your main speakers, add upper bass to fill in those speakers’ deficiencies, flex your walls with heavy-metal music, or correct room effects? My very sensitive Affirm horn speakers extend down to just below 50Hz, but above that produce very fast, detailed, tuneful bass. While they’re satisfactory with most music, I felt that augmenting the lowest bass would reveal further useful musical information. That was my plan: Above 50Hz, the bass would come from the Luminations; below 50Hz, from the Fathom f110s.

I began by placing the JLA subs to the outside of my Luminations and the same distance from me as were the main speakers. I used Wireworld Oasis 5 unbalanced cables to connect the Audio Research LS26 linestage to the f110s, although JLA strongly recommends using balanced cable. Hey, you use what you have, and these 4m cables were among the few in my collection long enough. To prevent the hum that often occurs when hooking up a sub with unbalanced cables, JLA has optical couplers at the sub’s unbalanced inputs, to block any ground-loop-causing current. Although I plugged the f110s into a standard outlet, not the dedicated circuit I use for my hi-fi system, there was no hum.

The Fathom f110’s superbly written manual instructs the user to use music or movie recordings with deep bass to set the sub’s output to match that of the main speakers, but that’s somewhat imprecise. I would have liked to see a CD with suitable test tones or musical examples included with the f110. But there’s a faster, easier, more precise way to do this: use a real-time analyzer (RTA), a spectrum analyzer that displays your system’s in-room frequency response. An RTA can be a program that runs on a computer (mine is), or a specialized, handheld unit like those made by Phonic.

Although my subwoofer-integration plan specified a crossover frequency of 50Hz, I wanted to verify that that frequency, which I’d chosen by ear, would really work. Sure enough, my RTA confirmed that the Lumination speakers provided pretty flat output down to 50Hz. I first used the RTA to set the level of each Fathom f110 to blend seamlessly with its companion Lumination. (Using the RTA reduced to a few minutes what could easily have taken hours, or even days.) Then, to minimize any residual room effects, I ran JLA’s A.R.O. program to ensure the flattest response in the room. The final bass response wasn’t totally flat, but it was flatter than pre-A.R.O. It was eerie to watch; with the RTA running on the computer, I could see the bass response flatten out as the A.R.O. worked its magic. The final bass response was essentially flat at my listening position to about 25Hz, dropping off by 5dB at 20Hz. That ain’t bad, folks.

Being of the lazy persuasion, I set the Power switch to Auto, so that the Fathom f110 would be turned on and off by the signal. It worked as advertised, except that the right-channel f110 occasionally turned itself on when the rest of the system was turned off. No harm done, just a bit weird.

I use Art Audio’s PX-25 single-ended-triode (SET) tube amp to drive the Luminations -- putting out only 6Wpc, it needs a very sensitive speaker. With the PX-25’s 0.7V sensitivity and the Luminations’ 103dB sensitivity, any sub that wants to play at the same level had better have lots of gain. The f110s had gain to spare.

There was a slight problem, however, with the combined load of the amplifier and subwoofer. Audio Research recommends a minimum load of 20k ohms for my LS26 preamplifier, and the combined load of the f110s and the Art Audio amp was a very low 9743 ohms, less than half the ideal minimum load. As a result, I thought the Art Audio’s performance suffered a slight loss of dynamics and speed. So the f110 would probably perform best driven by a preamp with very low output impedance, like you’d find in some solid-state units. Many tube preamps have even higher output impedances than mine, so could have the same problems mine did. I tried using my Audio Research VS115 amplifier, driven by balanced cables, and didn’t observe the same problem I heard with the PX-25. That was probably due to the fact that I used balanced cables between the preamplifier and the VS115.

How to assess how well a subwoofer works in a two-channel system? As I see it, it must pass two tests: 1) Does the sub go low enough and loud enough to satisfy your needs? and 2) Does the sub blend well enough with your main speakers to seem like an extension of those speakers?

For Test 1, the answer was a resounding “yes.” This baby subwoofer in the JL Audio line produced clean, effortless bass at whatever frequency I asked of it. And, as noted above, its output was flat down to almost 20Hz. Nor was it wimpy bass -- it kicked major butt!

Test 2 was considerably more important to me. It’s not much of a challenge to produce a lot of energy in the lowest octave, but it is a challenge to a subwoofer to keep pace with a really fast main speaker. I’d planned to search out recordings that would test the Fathom f110s’ performance, but before I did, the perfect reference track presented itself. Just for fun, I was listening to Erich Kunzel and the Cincinnati Pops’ Russian Nights (SACD, Telarc SACD-60657). At one point in a relatively quiet passage, a kettledrum is struck. The drum stroke went down deep, with considerable power. The Luminations got the upper overtones of the note, but obviously didn’t get the fundamentals. With the f110s installed, I could hear the entire note, from the deepest fundamentals to the highest overtones; it sounded just like a kettledrum in a concert hall. I could hear the mallet striking the head, the powerful transient it produced, and the decay of the note as it decayed into silence. And it had all the power it needed to carry to the back wall of the room, just as a kettledrum would in a concert hall. I couldn’t identify the transition point between the horns and the subwoofers. This was precisely the goal of my transition plan: to add an extra octave-and-a-half of bass that sounded just like the fast, detailed bass from my horn speakers.

Recalling that the double bass plays notes down to about 41Hz, I cued up the SACD remastering of Patricia Barber’s Nightclub (Mobile Fidelity Sound Labs UDSACD 2004). It has some very low notes on the electric double-bass, played energetically by Michael Arnopol. With the Fathom f110s installed, the lowest notes sounded more complete (i.e., I could hear the deepest frequencies) and much better defined. And, as before, I couldn’t tell whether the sound was coming from the horns or the subs. So Test 2 -- a seamless blend in which the subwoofer’s output sounds like an extension of the speaker’s output -- was also passed with flying colors. The JL Audio Fathom f110s had scored 100%.


In all phases of the review, it was obvious to me that JL Audio knows how to design a subwoofer that will work well in a real-world system. From the hum-preventing optical couplers on its RCA jacks to the comprehensive controls on its easily accessible front panel to its exquisite finish, the Fathom f110 is replete with features that made me want to use it in my system.

Of course, all these features would be for naught if the Fathom f110 didn’t also sound good, and it was here that this little sub really shone. With powerful, very-low-frequency extension worthy of a home-theater system, the Fathom f110 proved fast and agile enough to keep up with one of the fastest speakers I’ve heard.

$2100 is pretty pricey for a 10” subwoofer -- but that’s like comparing Chevy’s Aveo with its Corvette. While they’re both cars, the Corvette provides a level of performance that’s totally beyond the Aveo’s capabilities. And while the Corvette is unquestionably expensive, you’d be hard-pressed to find a car that provides more performance at its price point. The Fathom f110 is similar: It’s not the cheapest 10” subwoofer on the market, but I challenge you to find a better one at its price -- or at any price. I haven’t.

. . . Vade Forrester

JL Audio Fathom f110 Subwoofer
rice: $2100 USD in Black Satin finish; $2200 High-Gloss Black finish.
Warranty: Three years parts and labor.

JL Audio, Inc.
10369 N. Commerce Pkwy.
Miramar, FL 33025-3962
Phone: (954) 443-1100
Fax: (954) 443-1111