Review: Alpha Design Labs ADL H118

When Furutech launched their consumer-oriented Alpha Design Labs line in 2011 with the GT40 USB DAC/phono stage, it was clear that the company - which has long had a solid reputation among old-school audiophiles as a manufacturer of interconnects, power supply components, and connectors - was making a serious commitment to serving the new breed of personal-audio enthusiast, without abandoning the gear-and-gadgetry enthusiasts who'd been the company's core fans so far.

Last year, ADL upped the ante with the Esprit DAC/preamp, the Cruise and Stride portable DAC/headphone amps, and a passel of purple cables for portable devices; this year's shaping up to be even more exciting, with the feature-packed X1 USB/iOS portable DAC and headphone amp and, of course, the company's first headphone, the  ADL H118 - which we've been spending a lot of time with lately.

The H118's a very interesting headphone; a lightweight folding portable with a high-end pedigree, with - so ADL claims - a voicing meant to be unabashedly audiophile. Is there room on the market for such a thing?


While here at S+V we've seen a wide variety of headphone designs, ranging from the sublime to the ridiculous, the H118 falls squarely in the middle of the road aesthetically, and that's not a bad thing. It's understated, with the main visual cues being the silvery alpha logo on each earcup and the triangular earcups. Overall it's reminiscent of an ATH-M50 that's been squeezed a bit - unpretentious and businesslike, so if you're looking for bling, this is not likely to be your headphone. Not a bad thing, in our opinion.

The  unassuming H118 folds down into a substantial zippered travel case. While it doesn't pack as compactly as some other full-size over-the-ear portables (the Logitech/UE 6000 and V-Moda M-100, for instance), it's not unreasonably large. As you'd expect from a product with a Furutech pedigree, construction is solid, though those put off by predominantly plastic construction for whatever reason may not be impressed. But there's no legitimate reason to worry about the durability of plastic these days.

Ergonomics are not quite as mainstream as the look, and that's likely to be the only polarizing factor in choosing this headphone. Earcups are small - and I don't have Dumboesque earflaps by any stretch of the imagination. I started to feel pressure on the upper part of my ear after about an hour; it's of course difficult to generalize but I'd imagine those with larger ears might want to arrange a long audition before considering these. Brent Butterworth (whose ears are a bit larger than mine) also found the H118 difficult to tolerate for more than an hour or so. The H118 ear cups are quite tall as well - probably great for those with long, pointy ears (small-statured Vulcans, perhaps) - but it actually made it difficult for me to get a good seal at the base of my ear until I broke in the pads a bit. I'd say there's room for improvement here, for sure.

And that's good, since there's little to complain about otherwise. The earpieces themselves tilt and swivel sufficiently to accommodate a range of wearing positions, and if you can cram your pinnae into the H118 in the first place I suspect you'll be able to find a position that works.

The cable attaches on the left ear cup, via a locking mini-XLR connector (the arrangement will be familiar to AKG fans); the connection is solid and secure, and of course allows for replacement with exotic cables if that's your thing; ADL's own iHP-35 line is compatible; we got to check out the iHP-35x ($99), with silver conductors and various cryogenically treated components. It's a solidly built cable, and more flexible and easy to manage than the stock cable, though it does add considerably to the cost of the headphones.

I'll admit to being a bit of a skeptic on this front personally, but if you're into the idea of cable upgrades the cost of entry isn't so bad (and the common connector means that third parties should easily be able to whip up exotic replacements should the ADLs catch on), and the hardware is pretty nice on the iHP-35x. Both cables we tried were 3 meters long; perhaps a bit lengthy for active use, since even the stock cable is as substantial as you might expect from an ADL/Furutech product; a more ready-for-action 1.3-meter version is also available if you plan to take these on the road.


Is the H118 the audiophile piece ADL set out to produce? Yes, and no - though far as relatively inexpensive closed-back portables go, it gets pretty close, especially in reproduction of vocals. It puts out a lovely midrange, in the context of a bit of a U-shaped overall response; tilted a bit towards the higher frequencies, that may not be to everyone's taste. But if you dig detail, appreciate clean mids, and you're looking for something that you can cart around easily, the H118 might be worth an audition.

Figuring that ADL's designers had challenging acoustic music in mind, I plugged the ADLs into my Mac via the iFi iDAC and iCAN (look for a review soon; I also drove the cans from a FiiO E07K and E12, as well as an Apple iPad and a Samsung Galaxy Note 2) and cued up Gonzalo Rubalcaba's take on "Giant Steps" (from The Blessing). Rubalcaba's piano is front, center, and bright, with every note of Rubalcaba's sheets-of-sound solo pretty clearly intelligible (no small feat given the tempo at which the trio takes the tune), with just a touch of stridency. It's bright, but doesn't rip your head off. Jack de Johnette's drums sound a bit dry, heads-and cymbals forward, but the ADL does capture the articulation pretty well. Brushwork is very upfront. Charlie Haden's bass is tight, if somewhat backgrounded here.

Solo piano really makes clear the brightness of the H118. I checked out Glenn Gould's 1982 take on the Goldberg Variations, and again, balance and detail are great - almost Gradolike, I'd say (so Grado fans looking for a closed-back portable alternative might be curious about these). Gould's command over dynamics and tone is clearly evident, though I'd say the piano sounds a little thin and the room a bit airless - Gould's trademark vocalizations are clearly in evidence however.

Jazz vocals are also clearly in the H118's bag;  Billie Holiday's voice on  "Love Me or Leave Me" (from Lady Sings the Blues) is very nicely presented here - the H118's excellent midrange presentation does the vocal justice; the texture of her voice clear over the orchestration.

Brent found that the H118 reminded him "...of some of the big orthodynamic 'phones we've heard. Even Donald Fagen's voice on 'Aja' (yeah, I know, way overmentioned on sounds natural, not annoyingly thin as it does with a lot of headphones. I heard just a trace of sibilance on a few cuts, but barely anything worth mentioning."

Changing gears a bit with Talking Heads' "The Great Curve" (from Remain in Light) I found David Byrne's voice quite upfront and and free of strain; likewise midrange and treble instrumentation (like the dueling rhythm guitars) has plenty of presence, with clear attack and placement in the stereo field. I didn't love the bass here; Tina Weymouth's killer groove here sounded a little indistinct and boomy for my taste - not enough subsonic depth, just a tad too much upper-bass honk. But that's by comparison to headphones with seriously tight bass like the HiFiMan HE-500. And given that, the H118 acquitted itself admirably. 

It was really only with more aggressive material that I felt the H118 wasn't quite up to snuff. "Cold World" (from GZA's Liquid Swords), the overall treble emphasis works well to maintain vocal clarity and to keep the sampled hi-hat groove moving; the low bass is mixed quite forward to begin with, and the the H118s don't get much more boomy or muddy than producer RZA probably intended, though there was some clearly audible distortion if I turned up the volume a bit. The tech-metal of Meshuggah's "Pravus" (from ObZen) suffered a bit on that end too; and the H118's mix of brightness coupled with a bit of fuzz in the low end made the track tiring to listen to. The ADL might not, I'd guess, be the best headphone for those into aggressive music. It's just not meant to give your eardrums a workout. But you should know better anyway, of course.


To measure the performance of the ATH-AD900X, I used a G.R.A.S. 43AG ear/cheek simulator, a Clio FW audio analyzer, a laptop computer running TrueRTA software with an M-Audio MobilePre USB audio interface, and a Musical Fidelity V-Can headphone amplifier. Measurements were calibrated for ear reference point (ERP), roughly the point in space where your palm intersects with the axis of your ear canal when you press your hand against your ear. I experimented with the position of the earpads by moving them around slightly on the ear/cheek simulator, and settled on the positions that gave the best bass response and the most characteristic result overall.

The frequency response of the H118 shows a strong peak centered at 2.8 kHz (which one often finds in headphone response measurements) and a broad, strong boost between 6 and 10 kHz. Adding 70 ohms output impedance to the V-Can's 5-ohm output impedance to simulate the effects of using a typical low-quality headphone amp has no significant effect on the headphone's response.

Total harmonic distortion (THD) at 100 dBA is rather high in the bass, measuring 5 to 8%. You'd probably notice this if you play music with lots of bass at high volumes, so maybe this isn't the best headphone for hip-hop or heavy rock fans.

Isolation is average, perhaps a tad less than average, for over-ear headphones: -4 dB at 1 kHz, and typically -20 dB at higher frequencies. Impedance runs about 72 ohms, while average sensitivity from 300 Hz to 6 kHz at the rated 68 ohms measures 104.3 dB. - Brent Butterworth

Bottom Line

For those with audiophile tastes who need a closed-back, reasonably affordable 'phone for use at the office or out and about (where, face it, Grados can make you unpopular), the H118's strenghts should outweigh its weaknesses (and a little extra low end comes in handy for commuters in noisy environments anyway. Mainstream pop and rock listeners will likely be happy as well - the ADL can deliver low-end thump and present vocalists in a good light, something that a lot of bass-forward cans have difficulty with. On the other hand I'd guess that metalheads (or those interested in any aggressive, heavy music with a lot of action in the low end - say serious hip hop heads or those into extreme electronics in general) aren't going to like it - there's just too much distortion in the lower registers, and the brightness makes the heavy stuff sound more cranky than angry. If you're tastes run in that direction and you want a closed-back portable, you might want to check out something like the V-Moda M-100 or Logitech/UE 6000.

But overall, the H118's bright tilt and well-mannered midrange means that the audiophiles the company had in mind will likely be quite pleased - and so may you.

SVCR's picture

I can't see FR graph