Airist Audio is a newcomer to the world of personal high fidelity audio. I don’t envy their position – it’s an increasingly crowded market. These days, there seem to be fewer ways for a product – whether amp, source, or transducer – to stand out. Airist’s first foray consists solely of a headphone amplifier, the Heron 5, whose price at the time of this review – $1,999 (see update in the ‘Conclusions’ section) – places it squarely in the upper strata of competition. It’s a gutsy move – and one that doesn’t quite pay off.
If price is commensurate with size, then the Heron 5 delivers. This is one bruiser of an amp. It weighs just over 15 pounds and the dimensions are more akin to what you’d find with an integrated amp for stereo duty than something dedicated to powering headphones. The innards are sheathed in aluminum while the design is minimalist modern with all fastening screws hidden along the bottom of the amp. It’s a clean, elegant look that’s spoiled by some rough edges along the sides of the top and bottom panels. I’m not sure whether this is singular to the amp under review, but it was somewhat disheartening when lifting it out of the box and feeling like your palms were going to get scraped in the process.
The front panel has two 1/4″ output jacks labeled ‘high’ and ‘low’ (more on this later). They’re flanked by a power switch on the left and a largish volume knob on the right, which controls a stepped attenuator rather than a potentiometer. The detentes, indicated by an audible click and tactile feedback when adjusting the volume, have a small amount of slop that seems out of place for a premium product.
The rear panel sports an IEC inlet along with balanced as well as single-ended inputs, though the amplifier design itself is single-ended only.
The amp looks gorgeous, but the overall build quality doesn’t quite live up to the promise of its appearance.
A quick push of the power button and the amp’s slow start function is engaged. The red line on the volume knob flashes for about five seconds while the circuits warm up and output is muted. When the line goes solid, you’re ready for tunes.
Now for the output jacks. You’d think that ‘high’ meant that you plugged in your high impedance cans here. Nope. That’s meant for the jack labeled ‘low’. Instead, as the manual states, the ‘high’ output is meant for low impedance headphones and “better impedance matching” while the ‘low’ output jack is for high impedance headphones and “better damping.” Got that? Yeah, I didn’t understand it either, but I stuck with the manual’s recommendations for the review period and used ‘high’ with my Audeze LCD-XC’s / HiFiMAN Edition X and ‘Low’ for the Sennheiser HD 600’s.
Much like my experience with the build quality of the Heron 5, the sonic performance was somewhat of a mixed bag. The amp exuded smoothness, unmistakable ease, and a huge soundstage that was impressive on certain tracks. Yet I also felt that it lacked definition in the bottom octaves as well as macro- and microdynamics. Its smooth character also had a tendency to gloss over texture and steal air from around the performers.
On “Send My Love (To Your New Lover)” from Adele’s latest album 25 (CD, XL Recordings, 88875176782), vocals came across as silky rather than soulful. The opening kick drum beat had decent presence but lacked tightness and plucked strings sounded just a touch blurred. Treble response seemed to be extended and even. The midrange and treble liquidity helped the Heron reproduce Florence Welch’s vocals on “Ship To Wreck” from How Big, How Blue, How Beautiful (CD, Republic, B0023122-02) without fatiguing the ears. The bass had nice tone, yet lacked some texture to give it a sense of realism. The Heron also seemed to lose a bit of its composure as the mix became more complex. It was harder to pick apart the contribution of the different performers to the track. This also was apparent on “Wildest Dreams” from Taylor Swift’s 1989 (CD, Big Machine Records, BMRBD0550A). The Heron started to flatten out the images once the vocals, strings, and bass beat were going full tilt.
While the Heron was adequate with modern fare, the amp struggled to reproduce an orchestra with life-like dynamics and dimensionality. Although its cavernous lateral soundstage certainly relayed a sense of scale on “Jupiter” from Holst’s The Planets (CD, Decca, 289 460 606-2), the Heron didn’t infuse the reproduction with the alacrity and boldness necessary to convey a true sense of the jollity that the god brings to the universe. Likewise with the final movement of Rachmaninoff’s Piano Concerto No. 2 (CD, Chesky, CD 2), the London Royal Philharmonic and Earl Wild’s virtuosity sounded tamped down and closed-in – as if the Heron 5 deflated the concert hall with a vacuum. Switching in Arthur Fieldler’s brisk interpretation of Chabrier’s “España” from Hi-Fi Fiedler (CD, BMG Classics, 09026-61497-2), led to the same results – a loss of dynamics, texture, and air.
Though some might find the liquid / textureless nature of the Heron 5 appealing, I think that Airist went a little too far in this direction. And while the amp is capable of driving headphones to loud listening levels, it doesn’t seem to know what to do with all the electrons it has on tap. The tonal balance sounds commendably even and the warmish hue it casts on the music is pleasing to my ears but the clarity, refinement, and dynamics that really scream “attention to detail” at this level of the hobby isn’t there.
The DNA Sonett 2, when last available, retailed for $1,400. Pretty much in the ballpark of where the Heron 5 was (originally) aiming for price-wise. The two amps are quite different, technically speaking. The Sonett 2 is an all-tube design vs. the Heron 5’s solid state circuitry; the Sonett 2 has a potentiometer controlling the volume vs. the stepped attenuator used on the Heron. Sonically speaking, the Sonett 2 couldn’t match the Heron in soundstage width and sheer size of the images being reproduced, but it handily outclassed the Airist amp in terms of refinement and bass control (yes – from a tube amp). Whereas orchestral works on the Heron sounded gray and muted, the Sonett 2 instilled a sense of realism with its dynamic shading , clarity, and dimensionality – it set free the musical notes that previously felt caged in. On the modern stuff, it added texture to vocals and instruments, tightened up the bass, and offered a more nuanced presentation that let me easily pick and choose which performers to follow within the mix, no matter how crowded the soundscape was.
Ultimately, my sense is that Airist somewhat jumped the gun on the Heron 5. From the build quality to its sonic performance, the amp feels more like a pre-production prototype than a finished product. Just prior to the publishing of this review, Airist Audio decided to slash the price of the Heron 5 in half to $999. It’s yet another gutsy move and one that I think Airist sorely needed to make. A decade or so ago and this amp might have been a strong contender in its original price bracket. Fast forward to the present and you’ll find plenty of companies offering more for less. Even at its new price, I have to reserve an unconditional recommendation – yes it’s that competitive out there. I sincerely hope that the folks at Airist learn from their experience with the Heron and I look forward to whatever else they have in store.
Headphones – Audeze LCD-XC, HiFiMAN Edition X, Sennheiser HD 600
Amplification – DNA Sonett 2
Sources – Ayre Acoustics C-5xeMP
Cabling – Analysis Plus Copper Oval-In, Analysis Plus Pro Power Oval
Power – Bryston BIT-15