I started out in multichannel, feeding the subs—either one or three—from the Sub/LFE (low-frequency effects) channel of my multichannel server. In that arrangement, the main speakers are running full-range while the sub gets only the LFE channel on tracks that have one. Post calibration, the results were rewarding, even though on music the LFE channel mostly tracks the low-frequency content of the front channels and contains little unique information. On a recent recording of Jean Guillou's organ transcription of Mussorgsky's Pictures at an Exhibition, performed by Zuzana Ferjencíková on Jean Guillou: Organ Works (SACD, MDG 9062089), I didn't hear any new notes, but I did perceive more solidity and definition in the pedal tones, whether I used a single f110v2 or three. As I turned up the volume, the balance between those low notes (so essential to this transcription) and the rest of the spectrum tracked more naturally than without the sub. On their own, the Revels (five of them for this test) could handle the load at any tolerable level, but the addition of the subs expanded the scale for which Guillou's original stereo recording of this repertoire (CD, DOR-99117) is revered.
All that is fine for a discrete multichannel system with a 5.1 system with large, full-range loudspeakers. But what about systems with smaller speakers, or with a prepro or AVR? With such systems, some form of bass management is required. The f110v2 subs do not offer a high-pass–filter option to roll off the bass from the main channel. Such full bass management is, of course, built into all prepros and AVRs and, with experimentation and effort, I could implement it in JRiver or Roon.
However, JL Audio offers an easier solution: the CR-1 Active Subwoofer Crossover (footnote 2). I inserted one between the L and R output of my preamp and the Left and Right inputs of the power amps and the subs.
D.A.R.O. cannot adjust the CR-1's settings; the CR-1 must be adjusted by the user independently of D.A.R.O. The CR-1 manual recommends making all the CR-1 adjustments before running the D.A.R.O. processor, but to me that seems illogical: Any settings in the CR-1 depend on what is downstream, and those settings will be compromised if the subs are EQ-ed post hoc (footnote 3).
The CR-1 has adjustments for crossover slope and frequency, sub/sat balance and damping in the crossover region, and JL provides excellent instructions for setting them by ear. I followed those instructions, but I also found it helpful to observe the OmniMic V2's live display of in-room frequency response during the process. The settings were unremarkable—except for my choice of 90Hz for the crossover, which is higher than I would normally choose, and high enough that at the top end, the bass can become directional; JL Audio recommends a high crossover point, so that more of the bass is provided by bass-specialist subwoofers—and more is equalized.
JL Audio also recommends stuffing ports and raising the crossover above the range where the port operates so that all low bass is from nonresonant, sealed woofers. I declined to stuff the ports, but with the ports' output down 20dB at 90Hz (footnote 4) and a 24dB/octave crossover slope in the CR-1, the ports should not be audible in this setup.
Deep listening
How do you audition a subwoofer? The obvious answer is to haul out the bass-buster recordings you use to show off your system. So that's what I did, in both stereo and multichannel. Since the CR-1 has a bypass button, I could instantly switch between my main speakers (stereo or 5.0) run full-range and the same set with one or three f110v2s taking over the bass. With my stereo bass chestnuts, Béla Fleck and the Flecktones' The Flight of the Cosmic Hippo (CD, Warner Bros. 9 26562-2, CD) and Mendelssohn's Organ Sonata for No.1 in F, with Thomas Murray (CD, Raven 390, originally from LP, Sheffield Town Hall S-13), the bass was tight, deep, and full. Both of these recordings are endowed with powerful lows, which even a single f110v2 delivered in spades while delineating individual tones clearly enough to reveal the harmonic progression of the music. From there, I went on to other old favorites such as the Telarc bass drum on the final march of the classic recording of Holst's First Suite for Military Band by the Cleveland Symphonic Winds (SACD, Telarc 60639); I relished its physical impact. In the same league but in multichannel, there's the final exclamation point (with bass drum) concluding Holst's ballet music from The Perfect Fool (SACD, Reference Recordings RR-146). No problemo, in stereo or multichannel, with either one f110v2 or three. That's what a good subwoofer can do when you are listening for bass and not paying a lot of attention to the music.
I moved on to a performance with a solo guitar where the music usually distracts me from the excellent sound: Tárrega's "Capricho árabe" from La Guitarra de Torres, played by Stefano Grondona (CD, Divox CDX 29701). The guitar's range extends below the 90Hz crossover of this setup, but this did not pose a challenge for decent speakers or a well-integrated sub. Grondona was recorded up close in a reverberant acoustic that endows his guitar with great warmth and weight. I have loved this recording for decades and carried it with me to many hi-fi shows, but it never sounded this good before. Replacing the excellent low end of the Studio2s with the tautly controlled f110v2 more completely disambiguated the sound of the guitar's lowest strings from that of the wood, without diminishing the warmth and weight of either.
Buster Williams's acoustic bass fiddle on Griot Liberté (SACD, High Note HCD 7123) goes down further below that 90Hz crossover; with the bass managed by JL subs, both the plucked and bowed tones are better defined in tonal character and space than with the Revels running full range.
To my surprise, the newfound clarity extended above the crossover and into the lower midrange. "I Heard It Through the Grapevine," the stereo original of the classic Marvin Gaye performance, on The Marvin Gaye Collection (SACD, Motown B0003502-36), is an anemic recording; even switching in the JL f110v2 couldn't add lipstick. With the multichannel remix, which is much better mastered, the addition of one or three JL subs cleaned up the bass and rounded and projected Gaye's voice. Creedence Clearwater Revival, on Cosmo's Factory (SACD, Analogue Productions, CAPP 8402), in stereo, benefitted both from improved bass definition and from enhanced vocal clarity.
I had to try my go-to recording of Finzi's Come Away, Death (SACD, 2L 2L-064-SACD). From the first note of the piano, I felt the presence of the instrument and that strange, detailed illusion of a large instrument on legs with space around it. Kielland's voice seemed more rounded, yet lighter. Stereo with one f110v2 or multichannel with three were equally ravishing, save for the ingratiating ambience of multichannel. I thought I really knew this recording, but the JL Audio subs and the CR-1 have enhanced my respect for it and my joy.
Instead of continuing with an extended list of striking moments (footnote 5), let's jump ahead to an orchestra-and-chorus extravaganza: Prokofiev's cantata Alexander Nevsky in a magnificent recording by Thierry Fischer and the Utah Choirs and SO (SACD, Reference Recordings "fresh" FR-735). From the opening chord, there was satisfying weight and texture in the lower strings; in the "Song About Alexander Nevsky," it was easy to hear the inner structure of the instruments and chorus. With the opening of the apocalyptic " Battle on the Ice," the double basses and the low brass growled with menace, and the timpani and bass drum made the ice-breaking tactile and almost visual.
Having accepted that the addition of the f110v2 and associated stuff suited me, I played a new 2L recording, Ole Bull - Stages of Life (SACD+Blu-ray, 2L 2L-159-SABD), which includes music for violin, pianos, and orchestra by the 19th century Norwegian virtuoso, often called "the Nordic Paganini." I loved an earlier recording of Bull's Violin Concerti (SACD+Blu-Ray, 2L 2L-067-SABD) from the same crew, so I had high expectations of both the music and the sound.
I was charmed and lulled by the sweet, sedate beginning of "Largo posato e Rondï capriccioso"; it put the image of the soloist and orchestra in my mind. Then, about 5 minutes in, a sforzando tutti hits with the impact of a small bomb. There's the timpani, right there on the front left, to the back of the orchestra (confirmed by the instrument map in the brochure); despite its apparent distance, it has weight and shape and specificity. Switch off the JL subs and, yeah, it's a nice tutti but nothing special.
Conclusions
I have learned that despite my abiding predilection, crossing over from main speakers to subwoofers at the lowest possible frequency is not a global solution. If the main speakers are placed for balance and imaging and not for optimum bass, and if one is using high-performance subwoofers with capable room EQ, such as the JL Audio f110v2 with D.A.R.O., a higher crossover point means that the optimized subwoofer is effective over more of a frequency range where room modes are important. A corollary benefit of bass management with equalized subwoofers is that the lower midrange becomes clearer and more transparent. This is apparent on human voices and many instruments.
I found that this bass management is subjectively more satisfying than simply having a subwoofer playing the LFE channel on multichannel music recordings.
The JL f110v2 is a mighty mite of a sub, conceding little to its larger brothers. Placing it up front in a stereo system, crossed over to the main speakers and, most crucially, matched to the room with D.A.R.O., it can extend and clarify the bass response of your system. For a large room and/or a multichannel system, the f110v2 can be daisy-chained to additional f110v2s (or e110s) to increase the amount of bass power available, to reduce the influence of room modes and let D.A.R.O. finish the job.
Footnote 2: See Larry Greenhill's review of the big brother f212v2 and the CR-1 for more details on the latter.
Footnote 3: I exchanged comments with JL Audio about this. They said that they would reconsider their recommendations.
Footnote 4: See fig.2 here.
Footnote 5: Here are three. The sprung-from-a-bow opening of Britten's Variations on a Theme of Frank Bridge (2L Records 2L125, SACD), the deep, plush bass ballast of Handel's Concerto grosso in G Major (Pentatone PTC 5186737, SACD), and the ripe bass and guitar that drive Keve Wilson's rendition of "Alone" (Pure Imagination, Composers Concordance Records COMCON002, CD).
The CR-1 has adjustments for crossover slope and frequency, sub/sat balance and damping in the crossover region, and JL provides excellent instructions for setting them by ear. I followed those instructions, but I also found it helpful to observe the OmniMic V2's live display of in-room frequency response during the process. The settings were unremarkable—except for my choice of 90Hz for the crossover, which is higher than I would normally choose, and high enough that at the top end, the bass can become directional; JL Audio recommends a high crossover point, so that more of the bass is provided by bass-specialist subwoofers—and more is equalized.
JL Audio also recommends stuffing ports and raising the crossover above the range where the port operates so that all low bass is from nonresonant, sealed woofers. I declined to stuff the ports, but with the ports' output down 20dB at 90Hz (footnote 4) and a 24dB/octave crossover slope in the CR-1, the ports should not be audible in this setup.
How do you audition a subwoofer? The obvious answer is to haul out the bass-buster recordings you use to show off your system. So that's what I did, in both stereo and multichannel. Since the CR-1 has a bypass button, I could instantly switch between my main speakers (stereo or 5.0) run full-range and the same set with one or three f110v2s taking over the bass. With my stereo bass chestnuts, Béla Fleck and the Flecktones' The Flight of the Cosmic Hippo (CD, Warner Bros. 9 26562-2, CD) and Mendelssohn's Organ Sonata for No.1 in F, with Thomas Murray (CD, Raven 390, originally from LP, Sheffield Town Hall S-13), the bass was tight, deep, and full. Both of these recordings are endowed with powerful lows, which even a single f110v2 delivered in spades while delineating individual tones clearly enough to reveal the harmonic progression of the music. From there, I went on to other old favorites such as the Telarc bass drum on the final march of the classic recording of Holst's First Suite for Military Band by the Cleveland Symphonic Winds (SACD, Telarc 60639); I relished its physical impact. In the same league but in multichannel, there's the final exclamation point (with bass drum) concluding Holst's ballet music from The Perfect Fool (SACD, Reference Recordings RR-146). No problemo, in stereo or multichannel, with either one f110v2 or three. That's what a good subwoofer can do when you are listening for bass and not paying a lot of attention to the music.
I had to try my go-to recording of Finzi's Come Away, Death (SACD, 2L 2L-064-SACD). From the first note of the piano, I felt the presence of the instrument and that strange, detailed illusion of a large instrument on legs with space around it. Kielland's voice seemed more rounded, yet lighter. Stereo with one f110v2 or multichannel with three were equally ravishing, save for the ingratiating ambience of multichannel. I thought I really knew this recording, but the JL Audio subs and the CR-1 have enhanced my respect for it and my joy.
Instead of continuing with an extended list of striking moments (footnote 5), let's jump ahead to an orchestra-and-chorus extravaganza: Prokofiev's cantata Alexander Nevsky in a magnificent recording by Thierry Fischer and the Utah Choirs and SO (SACD, Reference Recordings "fresh" FR-735). From the opening chord, there was satisfying weight and texture in the lower strings; in the "Song About Alexander Nevsky," it was easy to hear the inner structure of the instruments and chorus. With the opening of the apocalyptic " Battle on the Ice," the double basses and the low brass growled with menace, and the timpani and bass drum made the ice-breaking tactile and almost visual.
Having accepted that the addition of the f110v2 and associated stuff suited me, I played a new 2L recording, Ole Bull - Stages of Life (SACD+Blu-ray, 2L 2L-159-SABD), which includes music for violin, pianos, and orchestra by the 19th century Norwegian virtuoso, often called "the Nordic Paganini." I loved an earlier recording of Bull's Violin Concerti (SACD+Blu-Ray, 2L 2L-067-SABD) from the same crew, so I had high expectations of both the music and the sound.
I have learned that despite my abiding predilection, crossing over from main speakers to subwoofers at the lowest possible frequency is not a global solution. If the main speakers are placed for balance and imaging and not for optimum bass, and if one is using high-performance subwoofers with capable room EQ, such as the JL Audio f110v2 with D.A.R.O., a higher crossover point means that the optimized subwoofer is effective over more of a frequency range where room modes are important. A corollary benefit of bass management with equalized subwoofers is that the lower midrange becomes clearer and more transparent. This is apparent on human voices and many instruments.
Footnote 2: See Larry Greenhill's review of the big brother f212v2 and the CR-1 for more details on the latter.
