Cavalli Audio is a well-respected producer of DIY headphone amplifier designs. As is often the case, these designs are the product of a particular and dedicated person, in this case Dr. Alex Cavalli. Cavalli has decided to move beyond the DIY market with the introduction of the Liquid Fire amplifier, which a fully finished (not kit-built) high-end amp available directly from Cavalli or from certain dealers.
FEATURES
The Cavalli Liquid Fire is a hybrid headphone amp, meaning that it uses a combination of tube- and solid-state-powered output circuitry. While hybrid circuits are not new, there are several aspects of the Liquid Fire design that are distinctive, as we have reported previously:
- First, the Liquid Fire uses an entirely DC coupled hybrid circuit, meaning that there are no capacitors in the signal path at all.
- All voltage amplification is handled purely by tubes, where the tube complement includes four JJ Tesla 6922 tubes—each of which has burned-in for 25 hours prior to shipment of the amp.
- The tube section of the amplifier is fed by its own dedicated dual (+/-) 100V power supply.
- A 20-second tube heater delay circuit (with color-coded LED indicator lights) ensures that tube warm-up is complete before the tube circuit is fully engaged.
- A combination of conventional and MOSFET transistors handles all power output amplification. (The MOSFET output stage is biased at 100mA and runs in Class A almost all of the time.).
- The solid-state section of the amplifier is fed by a separate, dedicated dual (+/-) 30V power supply.
- An opamp servo circuit ensures that DC offset is held at 0VDC.
- A 20-second output delay/DC offset detection circuit (again with color coded indicator lights) ensures that power output circuitry is properly warmed up, and DC offset is properly set at 0VDC, before the headphone output jacks are enabled.
- Key amplifier components (chassis enclosure, RCore transformer, piezo-electric power switch) are U.S. made.
In a move that I consider near-genius, Cavalli offers the amp with two headphone jacks, one providing 1/4 ohm output impedance and the other sporting your choice of 1/4, 50 or 100 ohm output impedance.
The amp strives to provide a best-of-two-world’s design, combining the transparency, harmonic richness, and sonic liquidity of great tube circuits with the cleanliness, precision, and control of great solid-state circuits.
The design reflects this approach. Some tube amps cultivate a deliberately retro, son-of-1950’s-vintage-McIntosh-amps vibe, but the Cavalli Liquid Fire sports a distinctly modern design. The moderately sized amp is housed in a matte black enclosure that sports two front panel tube viewing windows, upon which is imprinted Cavalli’s signature “yin/yang” logo. If you look closely, one side of the yin/yang panel features the schematic symbol for a vacuum tube, while the other features the symbol for a transistor. The Yin/Yang theme is repeated in the top cover ventilation scheme.
Balancing all those goals is a tall order, though Chris Martens’ First Listen article suggested good things ahead. In any event, I was anxious to see how well Cavalli succeeded.
SONIC CHARACTER
The Liquid Fire is one of those extremely good amps that is hard to review because it really doesn’t contribute any obvious or readily identifiable sonic “flavorings” to the music at all, which is a good thing. If you think about it, you’ll realize that in some sense the perfect amplifier would have no sound of its own—it would simply get out of the way and let the music through. The Cavalli more closely fits that ideal no-sound-of-its-own paradigm than other amplifiers I have reviewed, though the Woo WA22 has a similar “issue” (i.e., offers similar sonic neutrality).
Still, it isn’t very interesting or helpful to just stop the review here, leaving the reader with the obvious implication to run out and buy this amp. Anyway, the Cavalli doesn’t sound like the Woo, so obviously there is something more to say. And, despite its sonic righteousness, I don’t think the Liquid Fire is the amp for everyone. More on that anon.
Based on experience, we could say there are four characteristics that distinguish good amps from one another. Let’s look at these in order to get a handle on what the Liquid Fire is and does.
First, the Cavalli deals very well with low-level signals. Low-level signals are critical for conveying the color of instruments (because the color often lies in the harmonic structure of the instrument, which consists of small overtones). Low-level signals are also essential for conveying a sense of the space in which the recording was made (because the “sound” of the space is represented by a series of reflections of lower and lower volume). The Liquid Fire allows you to hear all sorts of these smaller signals, whereas some amps either blur them or bury them in noise.
Second, the Cavalli offers excellent instrumental separation. Some amps, when confronted with complex arrangements, smear the instruments together a bit. But the Cavalli is stunningly realistic on this score.
Third, and unlike some amps known for their transparency, the Cavalli has a solid ability to convey the smoothness, richness, and warmth of well recorded music. Too many amps put a little edge on treble transients, and you get the sense that their low-level signal handling is more a matter of artifacts than of simply reproducing the original recording. That just isn’t the case with the Liquid Fire. If anything, it sounds slightly mellow, but in a way consistent with live music. In particular, it doesn’t blunt the edges of fast-rising transient sounds.
Fourth, the amp can drive pretty much any headphone we have in the Lab, including the Hi-Fi Man HE-5LE and HE-6, as well as the Sennheiser HD800. This is important if you use multiple headphones or wish to change headphones periodically. It is also a comment meant to convey the fact that the Liquid Fire has plenty of dynamic range, though I did think on certain high-level sounds the Liquid Fire could sound a bit pushed.
So, with this rather strong endorsement in mind, are there any limitations or flaws to be found here? Well, if you’re willing to pay careful attention to the following words, I’ll say “yes.” The Liquid Fire has slightly less mid-range or treble emphasis than some competing amps. I’m tempted to say that the Liquid Fire is accurate and the competing amps are colored, but this is really very hard to know. It is more logical and useful to simply say that if you want to maximize clarity or openness, you might find another amp that fits better (or worse) with your headphones. At the same time, if you want to retain excellent clarity but also the inherent natural richness that is in your music, the Liquid Fire probably should be your first stop in this price range. At the same time, be aware that the Cavalli is not a soft-sounding amp, so if you want to smooth things over or apply tone controls, the Cavalli (like any other good, accurate amp) probably won’t be your flavor of choice. But, assuming we’re talking about very accurate amps, then the distinctions I draw here are akin to Ferrari vs. Porsche kinds of distinctions, not a matter good vs. bad.
MUSICAL EXAMPLES
On “Wildhorse”, from Glikyson, Gorka and Kaplansky’s Red Horse [Red House Records], the sibilants were natural and the backing vocals had good space; each instrument stood out clear, and yet was properly placed forward or backward in the mix as the producer no doubt intended.
The instrumental separation on “Last Known Surroundings” from take care, take care, take care by Explosions in the Sky [Temporary Residence] was pretty impressive—the amped-up sound of this track could easily be rendered as mush through some amps, but through the Liquid Fire it wasn’t. Also, when listening to this track through Sennheiser’s flagship HD800’s, the Cavalli did a good job of controlling the typical “splash” of those headphones.
Indicating the power and control of the amp, the bass drum on “Calamity Song” from The Decemberists The King is Dead [Capitol], was solid and well defined. The acoustic guitar on the track was clear as well, though the top-end snap might have been a little rounded-off.
Cymbals on Shelby Lynne’s “I Cry Every Day” [Suit Yourself, Capitol] seemed clear and clean, even though the cymbals were place well back in the mix—an indication of the amp’s excellent rendition of spatial cues. Instrumental separation, too, was excellent, especially with the electric organ, for example, which came through very clearly even though it was positioned off to the side of the soundstage.
Brandi Carlile’s “Looking Out” [The Story, Columbia] has an opening acoustic guitar that sounded very well balanced. This track exhibits a tearing sound in the high frequencies that the Cavalli rendered clearly and cleanly, and without becoming upset. Again, instrumental separation was excellent.
VALUE
As always, I start with the standard caveat that value is a function of your budget and your needs. Speaking outside that context, we can use the “show me better for less” test. On that basis, I think the Cavalli Liquid Fire fares quite well. You will have a hard time finding an amp that offers a more balanced set of sonic characteristics for less, and I would go so far as to say that you will likely have a hard time matching the Liquid Fire, even if you’re willing to spend more.
You can, of course, find an amp that costs less. At that point, determining whether the Liquid Fire is “worth it” is a matter of weighing the value of the sonic subtleties that are the hallmark of this design.
CONCLUSION
Consider this headphone amp if: you want an amp that avoids distortions and artifacts across the entire frequency spectrum, sounding natural with a wide variety of headphones.
Look elsewhere if: you’re looking for an amp to correct a particular deficiency of your headphones, or one which has a sonic character that pleases you, albeit without being particularly accurate. The Cavalli is committed to sonic neutrality on a 24/7 basis.
Ratings (compared to similarly-priced headphone amps)
- Tonal Balance: 9.5
- Clarity: 9.5
- Dynamics: 9.0
- Output Flexibility: 9.5
- Value: 9.0
BOTTOM LINE:
The Cavalli Liquid Fire offers state-of-the-art performance as judged against the key parameters we find most important for headphone amps. It hews toward naturalness rather than offering (or imposing) dramatically shaded colorations.
SPECS & PRICING
Cavalli Liquid Fire Hybrid Headphone Amplifier
Circuit Concept: 6922tube voltage gain, Transistor/MOSFET power output
Input: unbalanced RCA connectors
Headphone outputs: 2 X 1/4″ unbalanced (second output offers choice of impedance)
Dimensions (H x W x D): 14” x 10″ x 3.5″
Power Output: 4W into 32 Ohms/650 mW into 300 Ohms
Weight: 8 lbs.
Power: 120V/240V, 60Hz/50Hz
Warranty: Two years, parts and labor; 90 days on tubes
Price: $2750 as tested (introductory price for initial production run, which has recently sold out), $3250 for subsequent production runs.
CAVALLI AUDIO
www.cavalliaudio.com
By Tom Martin
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