The AudioQuest NightHawk Headphones

Publisher’s Note: While I had a blast using the AudioQuest NightHawk headphones playing video games with my PS4, the team at AudioQuest did a lot of work on these wonderful headphones, so it only seemed proper that we put them through their paces as a “real headphone user” would.

So here is John Darko’s take on the NightHawk from that angle.

You can read more of John’s work here: We suggest you do so, he’s a clever chap.

But now, the review!

When AudioQuest asked exWestone engineer Skylar Gray to tackle their first headphone the design brief comprised only a single sentence: “Just make the best headphone you can make” . Implicit in this instruction was the new model would not be designed to a price. Early credit goes to Gray then for not going large and turning in a design that isn’t outrageously expensive by even today’s standards: a pair of NightHawk are yours for US$599.

Following the notion that ‘everything matters’, no stone was left unturned throughout the design process. Firstly, from a consumer point of view, there’s the ‘unboxing’ that isn’t. Gray pushed hard to have AudioQuest dispense with wasteful outer packaging. The NightHawk’s leather carry case is wrapped in a simple cardboard sleeve. Detach and unzip.

When first pulling the NightHawk from their case it’s obvious that these headphones are a break from the norm. Their semi-open backed design concedes diddly squat to contemporary aesthetic trends. Working from the ground up, Gray attended to how each and every facet of a headphone can influence its sound. The headband is made from stainless steel and wrapped in two layers of resonance damping rubber before a final layer of fabric is applied. The headpad, made of leather and microsuede, suspends a semicircular yoke that in turn attaches to the earcup’s 3Dprinted grille via silicone bands, a material that was stress tested to five years’ wear and tear before being chosen over the less costly Neoprene (a distant second).

Not only does this structural arrangement provide proper decoupling of ear cup from headband structure which can introduce unwanted resonances but it also has ergonomic advantages. If headphone comfort is of high priority, the NightHawk phones are up there with the best: they’re lightweight with only the mildest of lateral clamping force. The headband ensures that leaning forward doesn’t cause them to tumble off the head. If they do take a dive, these headphones’ seemingly fragile physicality could be their undoing; sans carrycase the NightHawks aren’t suited to bag life as well as other models (hello OPPO PM3).

Gray claims “a material with good acoustic properties” was required for the ear cups themselves. Kinda obvious, huh? Not so fast. The first casualty was a plastic that was not sustainable, leading Gray to test metal and wood. Viscoelastic rubber that turns sonic energy into heat wouldn’t sufficiently damp metal’s tendency to ring and wood didn’t pass muster due to its inherent inconsistencies, nor would it lend itself to being machined into complex shapes.  MDF failed to pass muster because the corners were too easily damaged.

Liquid wood sidesteps the subtractive manufacturing process required by the other materials and is sustainable. Win and win. Those who have seen the dashboard of a recent luxury car will be familiar with the highgloss burl is capable of. It’s also used to make lampstands and shoe heels. What you might not know about liquid wood is that it arrives at the factory as a pellet. Only when heated does it change to the liquid state required for injection moulding. The liquid wood pellets for the NightHawk are sourced from Germany and moulded in China, where final headphone assembly also takes place. The grilles are 3Dprinted in France, with the driver magnets and aluminum parts sourced from Japan, making the NightHawk a true multicultural product.

However, AudioQuest remains tightlipped about the source of the NightHawk’s driver material for which Gray refused to go with off the shelf materials. “It’s not in my or AudioQuest’s DNA,” he says. “The norm.” as Gray describes it “is a Mylar film that works well in small sizes but is constantly flexing and changing shape.” The latter reportedly causes low frequency distortion adding colouration above 3kHz. Gray calls this the “easy, cheap route”.

After dismantling numerous similarly priced rival models Gray, like all good designers, asked, “How can I do this better?”. Sony’s long gone but much vaunted MDRR10 headphones take the inspirational credit for the NightHawk’s biocellulose driver, a material made from bacteria feces reportedly costing twelve times that of your average dynamic driver to make. This material comes to life by feeding bacteria cultures carbohydrates, causing them to excrete a fiber, cultivated after several weeks, then dried and cleaned before being pressed into 50 micron thick sheets. The 42mm NightHawk driver diagphragms are cookie cut from the sheets. An 8mm driver surround keeps the drivers pistonic motion from distorting the shape.

With their roots in cables, AudioQuest supplies two with the NightHawk: a thinner cable with gold plated plugs, not designed by AudioQuest themselves but able to withstand the bending and winding of mobile use. A second, thicker, solid core, balanced cable with silverplated connectors that won’t withstand endless bending, but takes design elements from the company’s loudspeaker cables, featuring “Solid Perfect Surface Copper+ (PSC+) conductors in a Double Star Quad configuration” is intended for serious, furrowed brow home listening (as conducted here by yours truly).

I’m not going to tell you that from the first note I was immediately struck by a sense of blah blah blah . In fact, nothing from the NightHawk’s presentation really stands out: no rambunctiousness (KEF M500), no overt bass heaviness (Sennheiser HD650), no super incisive treble (Sennheiser HD800). In trying to assess the NightHawk’s personality, I learnt that there wasn’t one to be found. That’s good for the would be buyer but gives a reviewer very little to get his teeth into.

I advise a little persistence to those dismissing the NightHawk as boring or plain after all but a casual audition. Their quirk free presentation will take time to win you over. More excitement can be had from the Sennheiser HD650 phones, which in turn aren’t as refined. However, you can’t run the HD650 so easily from a smartphone…which brings me to the NightHawk’s real talent: they don’t need a lot of juicing to get going. An iPhone or an Astell&Kern AK Jr. will suffice.

The NightHawk’s lean towards finesse and delicacy (as opposed to overall heft and weight) means they don’t necessarily benefit from the additional tonal colour of tubes. Straight talking amps are the order of the day here: the Resonessence Labs Herus or further up the food chain the Chord Hugo. Heck, even AudioQuest’s own Dragonfly is a solid match and one that will have upgraders struggling to justify the additional expense of only minor superior performance wrought by better amplification. That the NightHawk offers an exit ramp from the hamster wheel of upgrades brings ‘em into everyman headfi territory.

Moreover, these are headphones for an oft neglected section of the market: owners of integrated amplifiers whose headphone sockets don’t do justice to the likes of tougher loads from MrSpeakers, Mad Dog, or Beyerdynamic’s T1. The AudioQuest’s 100db efficiency displays none of those rivals’ tendency toward stridency when underpowered. After all, the headphone output on your average integrated amplifier is designed more to complete a functionality checklist than drive specialist headphones; only low-impedance models need apply. Thankfully, the NightHawk come it at 25 Ohms nominal, making them a shoe-in with portables and dongle DACs.

The upshot? You can’t please all of the people all of the time, but with their NightHawk headphone, AudioQuest gets pretty darn close.

The AudioQuest NightHawk

MSRP:  $599

Clones Audio 25i Integrated Amplifier

What started as a one-off unit intended as a family birthday gift has blossomed into a full-fledged audio equipment manufacturer. Hong Kong’s Clones Audio now counts monoblocks and a DAC among its product roster, but its 25i amplifier ($865/€629) is what jump-started the boutique manufacturer. The 25i, which is a 25 watts-per-channel integrated amplifier, was inspired by a 47 Labs’ circuit design that later landed in the public domain for the DIY crowd. After all, not everyone would see the $3,000-plus asking price of the 47 Labs’ Gaincard amp without wincing—and some might double over in pain upon seeing its internal part count.

This shoebox amplifier’s genetic connection to the circuit design from 47 Labs’ founder Kimura-San makes the 25i a proper Gainclone. Little wonder then that Clones founder Funjoe went with a brand name that connotes body doubling. His integrated amp mirrors the Gaincard’s short-as-possible signal paths and broader emphasis on circuit simplicity. None of the 30 dB gain comes from the pre-stage; it is only present for input selection, of which there are three. At the business end of the 25i is an in-house-designed board that houses Texas Instruments LM3875 amplifier on a chip.

Funjoe describes his clone as using “no protection print oil to enhance clarity of sound image and musicality.” That’s funny because clarity is also the first descriptor that comes to mind when trying to encapsulate the sound of the 25i. The other word that keeps surfacing is fruity. The 25i offers solid punch, dynamics and tonal color. It’s possibly not quite as zippy as Peter Daniel’s similarly Gaincloned Patek integrated amp, but the 25i fleshes out more acoustic mass to keep the trade-off seesaw perfectly balanced.


First up: the REDGUM RGi60, which is made in Melbourne and is somewhat of a reference at Darko HQ Down Under. The 25i trades in some acoustic mass for upper-midrange zip and caffeination, which lends it that sports-car vibe: a speedy ride with the top down. The REDGUM is warmer, more majestic and better suited to source material like the valium-drenched sound of Lampchop’s Nixon. Conversely, Morrissey’s Your Arsenal really benefits from the Clones’ keener energy with transients that, via the REDGUM, come across as softer and more rounded.

The 25i looks down its nose at the NAD D 3020. The little Gaincloner is an altogether more refined and nuanced listen that those with more luxurious transducers are likely to appreciate. This by no means negates the NAD’s far more impressive feature-driven bang for buck, but the NAD gets found out long before we call time on the Clones.

Playing week in and week out with Wadia’s 151PowerDAC Mini calls for intervention from of one of neatest budget thumb-DACs currently doing the rounds, one that won’t physically crowd out the 25i itself and keeps the DAC-amplifier combination costs within range of Wadia’s all-in-one unit. I lassoed Resonessence Labs’ Herus to the Clones integrated with a ZuAudio breakout cable. The Wadia and Clones/Herus pairing shares similar high-relief edge definition, but the latter steps forward with the larger soundstage. Similarly, the Clones plates up more body, but (crucially) it does so without bringing with it the fuzzier definition that could be attributed to the likes of Rega’s excellent Brio-R.

Loudspeaker Matches

With the French Atohm GT1.0 ($3,440/€2,500), things can get a little too bitey up top when less-than-stellar recordings are running higher SPLs. Thankfully, the Atohm has adjustable tweeter gain on the rear for such occasions. With the top end dialed back, this co-habitation proves to be one I could happily live with long term. I’m not saying the Clones is bright per se; that B word is too blunt an instrument and one that fails to connote this shoebox’s ebullient handling of subtlety. The abundance of micro-dynamic flair might not suit everyone, especially those whose systems are already strong on lower-treble caffeination.

As such, I’d peg the Clones integrated as ideally suited to lusher loudspeakers. Harbeth’s C7ES3 immediately springs to mind. And don’t think for a moment that a $1,000 integrated has no place driving loudspeakers four times its sticker—Funjoe’s shoebox is a genuine over-achiever.

Don’t have Harbeth money? Don’t fret. Wharfedale’s limited-edition Denton loudspeaker is one that channels a vintage vibe in both looks and, to a lesser extent, sound. They definitely lean towards a warmer, thicker-aired presentation and the 25i is just the (dream) ticket; it’s a match that’ll keep your total system cost under $2K. This Gainclone is the hot blade to slice through the Denton’s butter, keeping tight control on the mid-bass so that things don’t get too rich. With the electronic-infused world music of Banco De Gaia’s Maya, bass notes are tight but abundant with texture.

I like this amplifier a lot. It’s no powerhouse and perhaps that’s the reason why I found loudspeaker matching to be more crucial than usual during my three-month audition time. However, find the right dance partner and the Clones 25i brings the goods: acoustic mass, illumination and tonal color, all in one tidy solution. Like the sound of this but need more power? Clones’ 55pm monoblocks might be the answer.

Don’t be fooled by the budget pricing, though. Know that the Clones’ integrated is a bona fide high/er-end wolf dressed in entry-level sheep’s clothing.

Additional Listening

By Jeff Dorgay

Everyone I know who’s had the good fortune to hear this little Clones 25i has really jumped up and down about it, so after the photos were taken I proceeded to really put this little jewel through its paces in the context of a $200K system. Yep, that’s no misprint. Running the dCS Vivaldi stack directly into input one and the output to the Dynaudio Evidence Platinum speakers proves interesting.

While this is clearly insane with a source and speakers of this caliber, it’s pretty obvious exactly what the amplifier in question can and can’t do.  No, it won’t be replacing my $84,000 pair of Pass Xs300 monoblocks anytime soon, but this little amp makes a very impressive showing. It drives the Dynaudios not only with ease but great control. Bass is tight and tuneful, with the high end being smooth and extended.

What you don’t get here is the level of nuance and refinement that the big-dollar stuff offers, but the overall tonality is very neutral. When I swap the dCS and Dynaudio combination for the awesome OPPO 105 disc player and my 90-dB Vandersteen 1Ci speakers, this little amp really blows my mind. The level of clarity for under a thousand bucks is nothing short of amazing, and comparing it to my other favorite benchmark in the class, the Rega Brio-R, I concur with Mr. Darko 100 percent.

Whether you are a budding audiophile or looking for a cool yet compact second system, I highly suggest the Clones 25i. It’s got the right stuff.

Resonessence Labs CONCERO

Following the success of their statement INVICTA DAC(CA$3,999) Resonessence Labs have fired their first salvo into budget territory.  They’ve come armed with two-for-one ammunition:  a USB-S/PDIF convertor and DAC packed into a single unit (CA$599).  You can purchase direct from Resonessence themselves or via their dealer network.  An additional $50 bundles Apple remote (for playback control and filter selection) and USB power supply (required for S/PDIF DAC mode) into the bargain.  Accessories aside, the whole shebang is manufactured and assembled right there in Canada.

Custom coding

On paper, basic expectations are comprehensively met: separate clocks for 44.1 kHz and 48 kHz sample rate families and an in-house coded asynchronous USB solution.  Concerned that it will introduce jitter, Resonessence Labs have dispensed with PLL circuitry.  No, it’s not another XMOS implementation.

A DAC’s sound isn’t uniformly influenced by the decoding silicon – there’s I/V conversion and output stage to consider – but its sticker price certainly is.  The CONCERO is the digital guts of the INVICTA wedded to a cheaper ESS Sabre chip – the 9023.  Remember: the INVICTA runs a pair of Reference ESS Sabre 9018 and sells for CA$3999.

Resonessence combines their own custom (FGPA) code and the Cypress CY7C68013 chip in a USB receiver that uses their own asynchronous code and handles remote functions.  Their designer Mark Mallinson emphasizes that “they spent a lot of time making sure that the speed differences between the computer’s clock and the high quality/low phase noise reference of their DAC’s don’t cause issues – the code is written to handle when the computer is both faster and slower than the source. This required a custom solution.”

Remote control, up-sampling and filters

Team Resonessence have pulled some neat tricks with the CONCERO’s functionality.  Hi-jacking an Apple remote control is a clever trick.

The up/down buttons toggle on/off states for digital and analogue outputs; useful if you’re keen to minimize internal processing but I could discern no audible benefit when doing so.  Play/pause and fwd/next sends the same signal back down the USB cable to your host computer; a real boon if your existing PC or Mac has no existing remote control receiver.  Windows users will require the USB Class 2.0 driver (downloadable from the Resonessence Labs website).  Windows 8 compliance is now in the bag.

Unlike the price- and function-matched rival UD384 from Taiwan’s KingRex, no external power brick is required for the CONCERO to get going.  It runs on 5V USB fuel.  Engineering smarts have been deployed here too: connect the CONCERO (via USB cable) to a host computer to enable USB DAC mode OR plug the same USB cable into a power-only ‘phone charging’ brick (supplied in the power pack) for S/PDIF DAC mode.


Julian Cope’s epic and sprawling Peggy Suicide is presented as full, smooth and rich.  It’s a sound that’s free from digital glare and metallic sheen.  Not as obviously detailed or airy as the Micromega MyDAC , the CONCERO is much more conducive to longer listening sessions.  Build quality on the Resonessence Labs unit underscores the toy-like appearance of the Micromega.

There’s more.  Pressing the menu button on the Apple remote cycles through three filters: native mode (logo blue), IIR filter (logo magenta), apodizing filter (logo magenta).  The latter two 4x up-sampling filters work their magic only when fed 44.1 and 48 sample rate material.  I preferred the IIR filter.  It demonstrated greater heft with lower frequencies and was more rhythmically self-assured than both native mode and the apodizing filter.  The latter revealed more air in recordings but strayed into brightness on occasion.

Whichever filter is preferred for one style of music might not be suited to another.  Spinning (an ALAC rip of) the original CD of Thomas Dolby’s Golden Age Of Wireless, the IIR filter tamed some of the needling transients and added a little body and drive.  On the other hand, the lighter, crisper native mode filter dials back some of the bass on already-beefy techno: Sigha’s Living With Ghosts or Surgeon’s Fabric mix being two such examples.  The take away here is that the user can tweak the sound to balance out their existing system’s sonic characteristics.

Higher sample-rated source material – or digital music already software up-sampled  to 88.2kHz, 96 kHz, 176.4 kHz and 192 kHz – is passed bit-perfectly down the chain; the filters remain dormant and the logo holds fast to blue.

The gift that keeps on giving

There aren’t too many combo currently units doing the rounds.  One could applaud Resonessence Labs for packing filtering flexibility into a six hundred dollar DAC and then go home.  But no.  There’s USB bridge mode too.

As a USB-S/PDIF convertor, the CONCERO is utterly superb.  The jitter-reducing sauce that got poured into the recipe brings greater fluidity to Peachtree’s Nova125.

In this reviewer’s broad experience with USB convertors, the CONCERO is the next device to join the Audiophilleo and John Kenny’s battery-infused modified Hiface as the goto models at their price point. If you find the Audiophilleo too dry or the JKSPDIF too smooth, a happy medium might be found with the Resonessence box: glabrous with excellent tonal saturation.  There’s less transient bite than the Audiophilleo.  Think black coffee laced with a few drops of cream.  Yum.

The same up-sampling filters are available in USB bridge mode but with some volume drop-away in all but native (blue light) mode, a necessity to avoid filter distortion on the digital output.

Note: both filter and native modes are level matched at 1.2V on the analogue outputs.  The Concero is quieter than rival units and possibly isn’t for ideal for those lacking headroom in their amplification chain.  Conversely, a cooler analogue output is suited those with too much headroom or those with more sensitive inputs on vintage amplifiers and receivers.

In a recent experiment to extract audio from an iPad with Camera Connection Kit and iFi’s iUSBPower, the CONCERO and iFi’s own iDAC were the only DACs to meet the challenge without issue.  A USB clocker and DAC for the iPad.  No other unit currently offers this one-two at any price.

A keeper

I could easily live with the Concero as a long-term decoder; its eloquence and articulation of musical spirit is simply terrific.  Selectable filters lift its flexibility when applied to different music genres (and listener mood) whilst the USB bridge operation is up there with the best of them at this price point.

For those wondering: yes, the Concero is a superior-sounding unit to the Schiit Modi.  It offers more refinement and tonal depth.  Modi aside, I can think of no greater bang-for-buck currently available in the budget digital space.  Hands down a triumph of innovation and sonic flair, Resonessence Labs’ CONCERO exceeds expectations by a healthy margin and then some.

Resonessence Labs CONCERO


Schiit Bifrost DAC

Cheaper DACs usually come with a slightly bitter spoonful of compromise. Manufacturer budget constraints mean less-effective jitter immunization or weaker power-supply regulation. Such shortcuts frequently tinge a DAC’s sound with a metallic edge, most easily heard on the decay of a cymbal strike or lilt of a piano. That natural shimmer present via more expensive models just isn’t there. In ultra-budget conversion boxes, soundstaging shrinks or inner-detail retrieval doesn’t plunge as deep. One must find the compromise with which they can live.

The Bifrost is the first of three DAC models coming from California’s Schiit Audio. Co-founders Mike Moffat and Jason Stoddard already weathered heat in audio forums due to their DAC’s FAQ page, on which they opine that USB-fed digital audio is McDonald’s in a world of healthier burger choices.

That said, they’ve taken the time to create a unique USB board for the Bifrost. It offers asynchronous transfer and handles up to 24/192. USB connectivity on the $349 baseline Bifrost is a $100 option at time of ordering, or $150 at a later date. And Schiit’s modular design approach means that any forthcoming DAC board upgrades can be retroactively fitted.

Inside, there’s no sample-rate conversion in the conversion recipe, and the chip choice—AKM 4399—is none too common. As evidenced by its established range of headphone amplifiers, Schiit takes pride in doing things its own way. Mavericks that dig the humor in flippancy? Perhaps.

My experience with numerous budget DACs mirrors the duo’s mirth toward USB audio transmission. All other things being equal, a budget DAC’s USB implementation isn’t as nourishing as its S/PDIF neighbor. Given both choices on a rear panel, I’ll run with the latter every time, even if doing so means spending additional dollars on an alternative transport or DDC. USB connectivity is little more than a handy convenience.

The Bifrost shows an even temperament across the frequency range; nothing stands out. It leans towards warmer sonic climes. Contrary to its tundra-evoking name, this new Schiit is more chili than chilly. Simple, clean cymbal strikes close each verse of The Rakes’ “Retreat,” but by way of the Bifrost, the music comes on as flavorful British indie-rock without the aluminum aftertaste. And a thicker mid-bass guitar and bass mulch keeps “Strasbourg” chugging, while Alan Donohoe’s boorish delivery never overbears during the shouty chorus.

Compared to my current king of the entry-level hill, the Audio-gd NFB2.1, Schiit’s debutant fares surprising well. It’s much easier to listen to for longer periods than its Chinese rival. The American contestant also wins on aesthetics and overall build quality—proving it’s possible to make something good, and for cheap, without having to off-shore the manufacturing process.

Under the Schiit’s command, pebbled smoothness underscores the languid seduction of Lana Del Rey’s debut EP. Indeed, the Bifrost is distinctly more laidback than the Audio-gd. On “Video Games,” the NFB-2.1 pushes a hint of caffeine into the upper registers of Del Rey’s mostly laconic delivery, translating into crisper transient definition of her inhale/exhale.

Schiit’s presentation also shows more connective tissue than the NFB-2.1; there are fewer spatial cues. If this DAC stand-off took place in the amplifier space, the Schiit would likely represent a tubular faction. Greater congeal means more forgiveness of poorer recordings and greater overall body. The thick synth lines underpinning Phones’ remix of The Rakes’ “Retreat” impact with more squelch than via the Chinese entry. The two units are pretty much matched for detail retrieval, with the Audio-gd stealing the lead with ambient decay.

Going back-to-back against the Schiit using Bjork’s “Hyperballad,” the NFB2.1 occasionally loses upper-mid composure. The Bifrost is kinder, warmer, softer. It also digs deeper into the lower bass notes. The Audio-gd box displays keener momentum, but is hampered by a tinge of brittle harshness when handling Bjork’s enthusiastic vocal turns. If the Audio-gd channels Jayne Mansfield, Schiit mainlines Marilyn Monroe. The former’s edginess is more arresting, the latter’s curvaceousness more seductive.

With a JKSPDIF MK3 turning USB into S/PDIF during these listening sessions, the latter still bests Schiit’s bespoke USB implementation. No shame in that. To their credit, Stoddard and Moffat narrow the quality gap between said input options. Performance disparity—transparency, tonal density, instrumental separation—between USB and S/PDIF (coaxial) isn’t as wide as with my other daily unit (a Rega DAC). The Rega’s sound connotes ectomorphic physique: lean, sharp, alert. The Schiit takes an endomorphic approach: rounded through the waist with a more obvious rear-end (ooh, matron!). The Bifrost’s treble errs more toward humid summer morning whilst the Rega’s cooler, damper autumn afternoon might be better suited to those already running tubes further down the line. The Rega works honeycomb crunch at its chocolate center, the Schiit yields praline and caramel.

For listeners that enjoy a warmer musical bath or whose setup is already (over)-enthusiastic at the top end, the Bifrost could well be the DAC to obtain. It doesn’t suffer the usual—and sometimes predictable—sonic compromises commonly found at its price point. Moreover, it isn’t better or worse than the Audio-gd; just different. And this distinction is a strong selling point.

As such, Schiit’s Bifrost concisely reveals there’s more than one route to happiness on the budget DAC trail. Additional applause goes to Stoddard and Moffat for making it all happen at a USA-based manufacturing facility. Excellent work, chaps.

You can read more insightful reviews from John Darko here:

The Schiit Bifrost DAC

MSRP:  Starting at $349