JL Audio Fathom f212v2 powered subwoofer & CR-1 crossover Page 2

I then returned the preamp's balanced interconnects to the CR-1's main stereo inputs, to once again access low- and high-pass filtering. I set the filters' 6dB corner frequencies to 80Hz, 24dB/octave. Playing the same digital file of uncorrelated pink noise, I set each sub's Master Level control to match its acoustic output to the Salon2's output by ear, and confirmed this setting using Audio Tool's RTA display. I ran separate FFT measurements of the room response of the high-pass-filtered Salon2s with subs muted (fig.3), to confirm the 24dB/octave rolloff of the CR-1's high-pass filter. Reversing the sub's signal polarity or turning on its Extreme Low Frequency (ELF) filter worsened the sound, so I left those in their default settings.


Fig.3 Revel Ultima Salon2s, uncorrelated pink noise before DARO, FFT display, 8Hz–2kHz, high-pass filter on, subs off, in-room response (80dB vertical range).

Last, I time-aligned the subs with the main speakers using the phase control on each Fathom's control panel. Barry Ober, JLA's home products senior tech support engineer, recommended that I use the 80Hz tone on Soundoctor's Test/Setup CD Version 2.7.2 to run a null test to precisely set each sub's phase control. I did this by reversing one of the speaker cables to the Salon2 in the same channel as the sub being matched. Playing the Soundoctor tone, I placed my head between the Salon2 and its partnering Fathom f212v2. Turning the sub's Phase knob slowly, I listened for a sudden drop in volume where the out-of-phase outputs of sub and speaker canceled out each other. I found the null point at the 20° setting. I then reversed the speaker cables on both Salon2s, to put each sub and its Salon2 back in phase.

Each sub's DARO program was run separately. After checking that the sub was in Master mode, I connected the microphone and cable supplied with the f212v2—JL Audio's instructions stress that this is the only mike suitable for use during DARO calibration—to the sub's front-panel jack, placed the JLA calibration mike on the back of my listening chair at ear level, and pressed the Calibrate button. The Calibrate LED began to slowly flash red, and within seconds the sub had begun to emit pink noise at high levels. After 90 seconds, the output droned for an additional 90 seconds. The pink noise was loud enough to rattle anything in the room that wasn't tied down, including a radiator cover at the base of the left wall. Then the Fathom f212v2 fell silent, its Calibrate LED glowing steady green. FFT measurements of the f212v2 alone after DARO tuning showed that the previous irregularities in room response had been minimized (fig.4).


Fig.4 JL Audio Fathom f212v2s, uncorrelated pink noise after DARO, FFT display, low-pass crossover filter on, Salon2s off, in-room response (80dB vertical range). Note that 55dB peak is diminished.

Finally, I switched on the full system. Its room response, 8Hz–2kHz, was more linear than I'd seen with the Salon2s run full-range alone (fig.5). I checked the lowest frequency bands of the half-step-spaced chromatic scale on Editor's Choice (CD, Stereophile STPH016-2). These were sharply defined and clearly heard, as were the 40, 31, and 25Hz 1?3-octave warble tones on that CD. The 20Hz band was not only audible, it produced a strong pressure wave in the room. Playing "True Blues," from Keith Jarrett's The Carnegie Hall Concert (CD, ECM 1989/90) with crossover filters on revealed no discontinuities between subs and main speakers. Whether the Salon2s were run full-range or the subs and main speakers were played with the CR-1 crossover inserted, the midrange and highs remained transparent, the soundstaging wide and deep, and there was no brightening or hardening of the sound.


Fig.5 Revel Ultima Salon2s plus JL Audio Fathom f212v2s, uncorrelated pink noise after DARO, FFT display, both filters on, both Salon2s and subs on, in-room response (80dB vertical range).

The CR-1 played a crucial role in this review, letting me hear the benefits of the Fathom f212v2s and bass management in my system. When switched in, the f212v2s increased the Revel Salon2s' bass power, dynamics, extension, and pitch definition. This was remarkable—I regard the Salon2s' bass response as being exceptionally good, yet I heard their bass improve when the stereo subs were playing. This was evident as I listened to John Atkinson's digital recording of the Toccata of Widor's Organ Symphony 5, performed by Jonas Nordwall at Portland's First United Methodist Church (24-bit/88.2kHz AIFF file). The full system better depicted the deepest (32.7Hz) notes' depth, power, solidity, and mass, but didn't distort or mask the upper registers' transparency. The lowest bass notes weren't so much heard as felt in my feet through the hardwood floor. I also heard this improvement when I played John Busby's recording of Master Tallis's Testament, by Herbert Howells, from Pipes Rhode Island (CD, Riago 101). With the f212v2s playing, the sustained 32Hz pedal note at the piece's end pressurized the air and rattled loose objects.


Second, the use of two subwoofers enlarged the soundstage, increasing the three-dimensionality of images and giving a better sense of the performing space. I heard this when I played a DSD64 file of a live recording of Michael Tilson Thomas and the San Francisco Symphony performing Beethoven's Symphony 7. Switching in the full system—two speakers and two subs—broadened and deepened the soundstage. And the f212v2's ability to throw a huge, broad, deep soundstage revealed a three-dimensional image of tympani in the Kyrie of Ariel Ramirez's Misa Criolla, conducted by José Luis Acejo (CD, Philips 420 955-2).

The Fathom f212v2's bass resolution was revelatory. When I played Don Dorsey's "Ascent," performed by Erich Kunzel and the Cincinnati Pops on their Time Warp collection (CD, Telarc CD-80106), the JLAs' imaging let me better distinguish the positions of the synth beats that move from side to side. Dynamics ranged from soft murmurs to a thunderous rumble as the synths blended into the sustained 31.7Hz organ note that begins Strauss's Also sprach Zarathustra on that same disc. The deep pedal notes in Gnomus, from organist Jean Guillou's performance of his own transcription of Mussorgsky's Pictures at an Exhibition (CD, Dorian DOR-90117), were more focused and deep—with the Fathom f212v2s switched in, I felt them mostly through my feet as the floor shook. It surprised me that the full speakers-plus-subs system reduced in level and focused the massive, almost infrasonic organ notes in Pie Jesu, from John Rutter's Requiem, performed by Timothy Seelig and the Turtle Creek Chorale (CD, Reference RR-57CD), to better balance the pipe organ with the soprano, chorus, and other instruments. Similarly, it was easier to follow organist Olivier Latry's pedal notes in the first movement of Saint-Saâns's Symphony 3, with Christoph Eschenbach conducting the Philadelphia Orchestra (SACD/CD, Ondine ODE 1094-5). These changes exemplified the quality of "better bass rather than more bass" that Kal described in his f113v2 review.

The JL Audio combo of Fathom f212v2 and CR-1 strongly benefited the quality, scale, detailing, and full power of orchestral music by enhancing the depth and width of the soundstage while revealing ambience cues. I felt and heard the jaw-tightening mass of the bass-drum strokes in the second section of Stravinsky's The Rite of Spring, performed by Eiji Oue and the Minnesota Orchestra (DVD with 24/96 WAV file, Reference RR-70 HDCD). They burst into my listening room as dense, concussive thuds with clean, defined leading edges.

The Revel-JLA combo delivered the deepest, most powerful synthesizer chords on my soundtrack recordings, particularly the growling, explosive, mind-jarring mix of synth and percussion that drives "Assault on Ryan's House," from James Horner's score for Patriot Games (CD, RCA 66051-2). The massive synth note that opens "Deeper Well," from Emmylou Harris's Spyboy (CD, Eminent EM-25001-2), was more focused and less blurred with the f212v2s in circuit—I could more clearly hear the words in Harris's song, as well as the drums and guitar.

For comparisons with the Fathom f212v2 I selected Revel's Ultima Rhythm2 powered subwoofer for its superior build quality, inclusion of low- and high-pass filters, and similar price. At $10,000, a Rhythm2 subwoofer costs the same as one Fathom f212v2 ($7000) with CR-1 ($3000). Adding a second f212v2 brings the total to $17,000. Both subs offer high power, great bass extension, powerful internal amplifiers, clean high- and low-pass filters, and delay adjustments to time-align the outputs of subs and satellites. And both are extremely heavy, requiring two people to unpack and move them into a listening room.

The Fathom f212v2's DARO is fully automatic; the Rhythm2's room-optimization system requires separate FFT measurements and hand-tailoring of individual equalizer frequency and Q settings. The f212v2 has 18 bands of equalization to the Rhythm2's 10. Unlike the Rhythm2, the f212v2 comes with four Waxman Super Sliders, a hard copy of its glossy, two-language comprehensive manual, and the calibration microphone and mike cable. The Rhythm2's manual, test tones, and most of its control functions are available as downloads from Revel's website.


On the other hand, the Rhythm2's single 18" woofer offers 50% more area (254 in2) than do the f212v2's two 12" drivers (168 in2). The Rhythm2's two internal amplifiers are 11% more powerful, with peak power ratings of 4kW vs the Fathom's 3.6kW. The f212v2 is taller and weighs 28 lbs more, making it harder to move around than the Rhythm2. The Rhythm2's Q-tuning of its equalizer bands offers a more fine-gained adjustment capability. Only the Rhythm2 can modify the sub and satellites' output to smooth the room response.

Both subs pressurized the air and vibrated the floor of my listening room while delivering similar deep-bass extension, pitch definition, dynamic range, and slam. With some recordings, the JL Audio combo of Fathom f212v2 and CR-1 created a deeper, wider, more three-dimensional soundstage than did a single Rhythm2. Because I didn't have a second Rhythm2, I couldn't determine if two of them could produce the same improvements in soundstaging.

With the release of the Fathom f212v2, JL Audio has made important changes to the f212's internal design, most notably the new DARO 18-band equalizer. This increased the precision and reliability of the sub's setup, and produced easily heard and measurable improvements in deep-bass clarity. The Fathom f212v2's sound was quicker, more solid, and had better bottom-end authority than did the v1. Two f212v2s significantly widened and deepened the soundstage, and better retrieved ambience cues. The CR-1 crossover was a godsend for blending of the outputs of speakers and subs, and it let me hear the improvements in real time when I switched in the f212v2s: increases in bass extension, pitch definition, deep-bass power, and soundstage imaging.

Those interested in buying the Fathom f212v2 should keep a few things in mind: First, this is an expensive subwoofer that will do best in large rooms. Second, it's the heaviest and densest audio component I have encountered—don't underestimate the challenge of moving it around. For this nosebleed price, demand that the dealer transport, unpack, and employ at least two people to move it into position. Third, realize that getting the best sound from the Fathom f212v2 requires time and patience, as well as learning how to use its controls. Set up poorly, one or two f212v2s can mess with your sound. To give you a leg up, ask the dealer to include an iTestMic, and to pay the iTunes bill for Audio Tools.

Reviewing the Fathom f212v2s let me experience once again the thrill of discovering n exceptionally powerful new subwoofer. And JLA's CR-1 electronics crossover was a total surprise—I wondered where it had been all my life. It's beautifully made, sonically transparent, performs a critical role in the optimal setup of subwoofers, and has ergonomic bypass and mute functions that let you immediately hear the sonic improvements of good bass management. JL Audio's Fathom f212v2 subwoofer and CR-1 crossover are strongly recommended.

JL Audio
10369 N. Commerce Parkway
Miramar, FL 33025-3921
(954) 443-1100

waynel's picture

"the Rhythm2's single 18" woofer offers 50% more area (254 in2) than do the f212v2's two 12" drivers (168 in2)"

Not sure if I'm missing something but the area of 2 12" circles is 226 in^2 so a single 18" would only have 12.5% more area.

also "This generated a flat room-response curve: ±3dB, 8Hz–2kHz (fig.1)
Really? that's not what I see in figure 1.