September 2012

Audio Electronics Nighthawk Headphone Amplifier
A stunning headphone amplifier that easily resolves instruments in great detail.
Review By Tom Lyle

  To begin this review, it is worth mentioning some history of the audio manufacturer Audio Electronics. Audio Electronics was formed in 1993 as a side project of renowned tube component (and these days, often solid-state and digital) manufacturer Cary Audio. Audio Electronics offered mostly tube amps that were more affordable than the Cary gear, and was less ambitious in design and build, but certainly very fine-sounding equipment. Cary Audio put Audio Electronics into hibernation for a few years, but they've re-launched the brand, its first product being the subject of this review: the solid-state Nighthawk headphone amplifier. Audio Electronics' products are sold through Cary Audio's website.

Rather
The Nighthawk is a rather large headphone amp. I've seen headphone amps that could fit in the palm of one's hand, although the majority of these units are meant to double as portables, and the Nighthawk obviously cannot function as a portable. Part of the reason of the Nighthawk's rather large size is due to its seriously large, low noise, over-built, fully regulated, discrete power supply. Its power supply is fed by a power transformer which is rated three times greater than required for the Nighthawk's design. Its "top quality" parts are mounted on a heavy-gauge fiberglass circuit board, and its large size might also be due to its internal components, which seem to be optimized for sonic performance with less regard to the component's dimensions. It’s all solid-state design is based on a monolithic JFET device which Audio Electronics claims was also chosen for its sonic traits. The discrete Class A output stage, "yields tremendous speed and bandwidth for very accurate musical reproduction". The output stage goes to a "fully complementary" high-speed buffered output stage to ensure high linearity and low distortion, which Audio Electronics says leads to musical accuracy. No global feedback is used, and the Nighthawk is said to be able to drive headphones with an impedance of 20 and 600 Ohms, which pretty much means any headphones which are likely to be in any audiophile's collection. The amp also has a five-second muting circuit which prevents noise when powering the amp. In their literature they also infer that the Nighthawk is voiced "not like typical solid-state".

The black cabinet of the Nighthawk measures 14.5" deep yet only 8.5" wide, which makes it a bit more space-saving than a full width component, but with such a depth it still needs quite a bit of shelf space. The front panel has a simple layout, which reflects the operation of the Nighthawk. On the left side of the front panel is a large, smooth running silver-colored volume control, to its right the 0.25" headphone input jack, and then the power button with a red indicator light above it. The back panel is just as spare – which includes a pair of RCA inputs and fixed outputs, and an IEC power cord receptacle.

I guess I should mention one thing right away that may be a deal breaker for some headphone aficionados: some may complain that the Nighthawk has too few functions to justify its price. There is only one headphone input, the unit does not have any gain sensitivity choices, and some might (heavens forbid) wish for some sort of signal processing functions. But as I'm (and I assume most of you are) more interested in sound quality than any bells and whistles that a headphone amp may provide, and so there weren't any times that I wished for any of these options – one input was perfectly fine because I'm a solitary listener, I didn't miss a gain sensitivity control because the gain was nearly perfect for any headphone I connected, and I would never, I said never, want to alter the signal beyond what the engineers, producers, and especially the musicians originally intended for me to hear, without any sort of sound processing.

The sources I connected to the Nighthawk were both analog and digital, the analog being a Basis Debut V turntable with a Lyra Kleos phono cartridge mounted on a Tri-Planar VI tonearm. The tonearm is wired with Discovery cable, which continues directly to a Pass Labs XP-15 phono preamp, which in turn was connected through its balanced outputs with MIT Shotgun S3.3 interconnects to a Balanced Audio Technologies (BAT) VK-3iX preamp. The digital front end was for the majority of the time a 3.20 GHz Dell Studio XPS PC with 8 Gig of RAM running Windows 7 using Foobar 2000 with the computer's ASIO'd USB output fed via DH Labs cable to either a Benchmark DAC1Pre or Wadia 121 USB digital-to-analog converter, the balanced outputs of which were fed to the preamp. The tape-out of the preamp was fed to the inputs of the Nighthawk, essentially taking the preamp out of the equation other than its short run of internal wiring and source selector. The headphones used were for the most part the top-of-the-line Grado PS1000. I had on hand quite a few other headphones, none of which sounded nearly as good as the Grados, including a high-ranking Sennheiser, but for this review the Grados were the cans I used for the evaluation, first and foremost because they were the not only the best in house, but the best I've ever heard, regardless of the amp driving them. My review of the Grados is forthcoming. But still, I also used other headphones, even some cheap-o models I had lying around just to see how things would sound with less-than-superb 'phones connected to the Nighthawk's input. My view of the Nighthawk’s sound quality is based not only with the Grado PS1000, but from what I heard with the others, although the PS1000's were the greatest in revealing both the Nighthawk's strengths and weaknesses.

I suppose that many will consider what headphone amplifier they are going to purchase based on their system and headphone preferences (and price), and thus many will read this review with these things in mind, at least I hope they do. But as my sources are at least above average (especially the analog), and the headphones I used for the evaluation are the stupendous sounding, and rather pricey, Grado PS1000 one would think I'm putting the Nighthawk through its paces in the best possible light.

First
My first impression of the Nighthawk was its transparent sound. I would go as far as saying if this is all one is looking for in a headphone amplifier, one need not look any further than Cary's webpage to order this unit. Yes, I've heard other headphone amps that are transparent, yet the Nighthawk was able to combine this transparency with a dynamic sound that not only was able to get its gain section out of the way of the sound, that is, it didn't inject any sound of its own, but simply increased the gain to a necessary level. It was able to drive a decent pair of headphones, but was also able to make music sound like music. This might sound simple, but many products sound "good" without sounding musical. This is more difficult than it might seem. It goes without saying (even though I just mentioned it) that this should be one of the most important characteristics any audiophile should look for in any piece of equipment that aspires to be included in one's arsenal. In addition to this, Nighthawk's musicality was not at the expense of separating individual instruments and sounds, as clarity was also one of its positive traits. One might assume that transparency and clarity are simply two terms for the same thing, and often they are, but in the case of the Nighthawk this meant that not only was I able to hear whatever the recording intended me to hear, but the resulting sound was involving enough to bring out the excitement in the music at the same time. Jump factor, if I may, although jump factor is usually associated with loudspeakers, it is often applicable to power amplifiers in that they have the headroom and can separate instruments that are playing the same volume simultaneously, and one follow these instruments throughout while the component's sound never loses its musical character. The Nighthawk is able to pull this off.

The above paragraph might seem to some as a bit disjointed, but what I'm getting at is that Cary and Audio Electronics have produced a product that is more than just a booster of the headphone's signal. It belongs in the class of components that come along all too infrequently -- one that seems to somehow sense what the signal is composed of and interpret it correctly. Many simply call this type of gear "musical" and that it has "rhythm" and "pace", and usually this type of equipment only comes from experienced designers. Cary, er, Audio Electronics are experienced designers. And as a bonus they have done this for a relatively affordable price.

Hearing the members of Amsterdam's Concertgebouw Orchestra perform Hindemith's Chamber Concertos (Kammermusik) conducted by Richardo Chially on the two CD set on London through the Nighthawk was as good as I've ever heard it. Once I was chastised by for letting someone know that I sometimes preferred the less popular Ensemble Modern version on RCA with Markus Stenz conducting, but have always come back to the wonderful performance that Chially draws from his Dutch outfit. These postmodern miniatures, which were written for smallish to slightly larger than medium sized groups and are called by Hindemith "Chamber Concertos", but are in fact more akin to plain concertos, period. Still, regardless of the size of the ensemble during these seven concertos, the Nighthawk managed to not only separate the complexity of sounds from each of the instruments, but when the pieces feature musicians that are practically playing the obtuse lines in unison each instrument can be heard individually. This is not to say that the Nighthawk is too detailed – when listening in a concert hall it is difficult to hear each instrument when it is playing in a group, but the amp's lifelike character was able to accomplish this feat as realistically as I've heard from just about any solid-state headphone amp. I felt as if I could count the instruments in the group that were performing. The solo instruments, whether string, wind, or horn, were reproduced with a lifelike quality that made the "soundstage within my skull" not that much of a deterrent to imagining the musicians playing this music, grouped on the stage in their street clothes peering over their music stands at Chailly. The Nighthawk's bass response was put to the test on the second movement of the Organ Concerto (No. 7), where in my mind's ear the lowest notes of the organ shook the air in the hall, as the higher notes floated in the air above the musicians and the empty seats. This is a great double-CD that is worth adding to one's collection.

I'm sure more often than not classic rock band's record companies re-release their material with cashing in as the only reason. The band members in all likelihood aren't in need of the two cents a copy they will split between them. Yet I was more than happy to acquire a new extended CD version of the Rolling Stone's Exile On Main St., and yes, I enjoyed hearing the "new" material on the second disc. But it also compelled me to pull the UK edition of the original LP off the shelf, clean it, and give it more than a few spins over the last few months. I'm as gullible as any in my age group, so "Tumbling Dice" was able to take hold and force me to play it numerous times. From Keith's squiggly guitar intro, to the Nick Taylor's overdubbed bass line where it is easy to hear that he's playing with a pick as opposed to Bill Wyman's customary thumb strokes, the Audio Electronics Nighthawk was quite at home reproducing this rocking tune. Again, its separation of instruments and groups of instruments, as well as the details that were made evident, such as being able to distinguish the two sounds that made up the simultaneous snare crack and tambourine hit on Charlie Watt's kit. It made the tune sound as intoxicating on this 3000's spin as it did when I first heard it on AM radio as a kid – except with the Nighthawk it was as if I was joining the band in the mixing sessions as opposed to just being a passive observer.

The only slight negative I can think of in regards to the Nighthawk's sound, in that it might be a bit on the dry side – and so there may be some headphone listeners that would prefer that the sound of the Nighthawk wasn't so honest. A tube unit it ain't. I do like to balance the sound of tubes with solid-state, so I'm likely to pair a solid-state amp with a tube preamplifier, or vice versa. To my ears, this is the best of possible worlds. I'm a little disappointed because about three weeks after receiving my sample of the Nighthawk, Cary introduced their $1595 HH-1 solid-state/tube hybrid headphone amp. Granted, it is $400 more expensive than the Nighthawk, and this might be more money than some would want to spend on a headphone amp in this class. Still, I hope I don't sound disgruntled. I'm not. I don't think anyone who purchased or is going to purchase the fine Nighthawk headphone amp should be, either. I could picture myself living with this baby for quite a long time, if not forever.

Awfully
The Nighthawk is an awfully good sounding headphone amplifier and I predict that they will sell lots of these sight unseen. Not only because of Cary and Audio Electronics’ reputation, but the good reviews that it is likely to receive in addition to mine. It might not be as flexible as some might want, and it is quite a large headphone amp. But the sonic positives outweigh these slight negatives by quite a large margin. It is a detailed, musical, realistic sounding headphone amp that can drive any pair of headphones it is likely to encounter. When matched with a top-flight set of cans such as Grados PS1000 the resulting sound is as good as it is likely to get in one's home. It is also able to drive much less upscale 'phones, too, and with great results. This unit is highly recommended – to anyone that wants get serious about their headphone listening experience – and will likely be the last headphone amp one ever purchases.

Specifications
Type: Solid-state stereo headphone amplifier
Input Impedance: 50 kOhms 
Gain: 20dB
Frequency Response 5 Hz to 35 kHz (-1dB) 
Signal to Noise Ratio >90dB at 0dB gain 
THD <0.01% 
Channel Separation >70dB/10kHz 
Output Power: 400mW/300 Ohms, 600mW/30 Ohms
Output Impedance: 5 ohms 
Dimensions: 14.5" x 8.5" x 4" (LxWxH)
Weight: 10 lbs. 
Price: $1195

Company Information
Audio Electronics/Cary Audio 
1020 Goodworth Drive
Apex, NC 27539

Voice: (919) 355-0010
Fax: (919) 355-0013
Website: www.CaryAudio.com