For this review I am using Double Helix Cables Ultrashort 2.5mmTRRS-to-4pin XLR balanced adapters. The inimitable Peter Bradstock was kind enough to provide a few of his excellent adapters for special Pinky use. $89.99, and you can run your balanced IEM cables right into a beefy amp like this.
The Cayin iHA-6 is clean and clear and very, very detailed. It aims for reference quality, and easily achieves it. Neutrality dominates the signature. It is not warm or bright, but reveals the nature of your DAC, allowing its color to shine through.
There is much air infusing Cayin’s naked, transparent profile. You could call it analytical, though I fear that is missing the point. Lively and complex sonics draw you into the soul of the music, making it hard to sit there and be critical. This is an amp for pleasure-listening.
Unlike many neutral amps, the iHA-6 is not dry or cold. No sharpness or stridency threatens treble notes. Rather, smoothness and refinement convey her clarity. The signal flows forth with depth and weight, delivering a fulsome, rounded timbre… or as much as can be found in such crystalline rendering.
The soundstage is of good size, with remarkable separation of elements. Wonderful contrast exists between the blackness of the background and the vibrancy of each note. You get excellent layering and depth. Cayin produces such a dynamic sound, with an abundance of both macro and micro detailing. It is, quite simply, a top performer.
For comparisons, I really have only the 2016 Amanero Audio-GD NFB-28 (round $800), which is a DAC/Amp combo. But it’s balanced, and around the same price, so it makes for a fine bit of competition.
The Audio-GD is bigger. Both physically, and sonically. The soundstage is greater on all axes. It possesses a far richer, warmer sound which presents as profoundly smooth. This come at a cost to transparency, and details are not as readily available. The low-end has more volume and body. Vocals have a slight lushness and romanticism about them. The treble is thicker, warmer, and sweeter.
The iHA-6 is hands-down the cleaner and clearer contender. It has a far more reference skew, whereas Audio-GD is all about that analogue musicality. Cayin highlights the intricate and subtlest aspects of a recording, making sure you catch everything. Audio-GD wants you to relax at your listening station and let the waves wash over you. With the NFB-28, the layers are not as sharply defined and the elements not as stark in their separation. Instead, you are treated to a cozy, velvety, experience, which still excels at clarity, if not as much.
Both these amps are more than capable of driving the most demanding headphones in the world, with relative ease, and scaling down the amperage to work well with sensitive IEMs. However, I did notice, hooking up something like Legend X to the NFB-28, I could not get the volume down to complete silence. With the pot turned all the way to the Off position, music could still be heard, though just barely. On the plus-side, though, the NFB-28 is hiss-free with the likes of Empire Ears Legend X, Custom Art FIBAE Massdrop Exclusive, and Noble Audio Kaiser Encore.
The same could not be said for the Cayin iHA-6. On Low Gain and Low Current, with all of those in-ears, there was noticeable hiss. Of course, when music is playing that gets pushed to the background. And if it still bothers you, there are inexpensive solutions, like the Dragon Tamer (iFi iEMatch, Review HERE) which will quiet that shit right down. Also, Cayin’s volume can reach a state of perfect silence, even with the super sensitive Encore. I don’t know why my NFB-28 can’t, but the iHA-6 has no trouble there.