HiFiMAN EF-6 Headphone Amplifier (Playback 61)

HiFiMAN Builds A Serious Heavyweight Contender

Returning, again, to the EF-6/HE-6 combination, I put on the very demanding “Gnomus” movement of Mussorgsky’s Pictures At An Exhibition as transcribed and performed by organist Jean Gillou [Dorian Recordings]. This track provides a serious bass workout (complete with loud low frequency passages that are richly detailed and nuanced, and that at times plunge to pitches almost below audibility), but also showcases the upper registers and varied voices found near the top end of the pipe organ’s frequency range. It is precisely the sort of track that can cause many headphone amplifiers to stumble, especially if they are attempting to drive the notoriously power-hungry HE-6’s. Yet in this environment the EF-6 positively thrived, making the passage sound almost frighteningly powerful and majestic yet—here’s that word again—at the same time curiously accessible. On this track more than many others, it became clear to me that the EF-6 is rarely if ever is daunted by musical challenges—especially challenges involving complex textures, timbres, and high-potency dynamics. It’s almost as if this amp lives to put challenging music back within our grasp, which is a beautiful thing to experience.

CONCLUSION

Consider this headphone amp if:

• You want an amp that has more than ample reserves of power, even when driving what many would consider fiendishly difficult loads—such as HiFiMAN’s own flagship HE-6 planar magnetic headphones.
• You want an amp that sounds muscular, yet without becoming “muscle bound;” on the contrary, the EF-6 is sonically nimble and agile.
• You want an amp that offers plenty of audiophile virtues, yet whose central appear is a rich and engaging quality of musical naturalism.
• You want an amp that can really make HiFiMAN’s magnificent HE-6 headphones sing, but that is no “one trick pony;” the EF-6 works very well with a wide range of upper-end headphones.

Look further if:

• Some of the “Caveats” mentioned under the FEATURES section, above, are troubling for you. The EF-6 offers tremendous performance potential and HiFiMAN has a good record in terms of standing behind its customers, but for $1600 you can and should expect a product (and product documentation) that is polished and refined in every way.

Ratings (relative to comparably priced headphone amps):

• Design and Features: 8 (see “Caveats” under FEATURES, above, for our “wish list” for enhancements we hope to see in follow-on models from HiFiMAN).
• Tonal Balance: 9
• Timbral Purity: 9
• Detail & Resolution: 9.5
• Imaging/Soundstaging: 9
• Dynamics: 10
• Value: 9 (if the design is stable); 4-5 (if the design continues to experience ongoing revisions, changes in features, etc.)

BOTTOM LINE:

As with certain Rolls-Royce automobiles, the power output of HiFiMAN’s EF-6 headphone amplifier could best be described by one simple word: “Adequate” (where we interpret the word to mean not just having enough, but more than enough power for any headphone load one might ever wish to drive).

But there’s more to the EF-6 that wattage alone, because this pure Class A design also offers speed, agility, clarity, low-level resolution, and plenty of refinement, plus a rare ability to help music sound richer, more vivid, approachable, and involving than it otherwise might. In short, the reason to consider buying and EF-6 involves not only the fact that it can drive just about any load, but that it can also pull you closer to your music.

Does HiFiMAN need to do more work to support this amp with proper packaging, documentation, and so on? Yes, it does, but the good news is that the EF-6 is a world-class amp that richly deserves the top-shelf support materials we hope and expect that HiFiMAN will soon provide.

SPECS & PRICING

HiFiMAN EF-6 Headphone Amp/Preamp
Type: Class A solid-state headphone amplifier/preamplifier
Accessories: None.
Inputs: Three switch selectable stereo analog inputs (three single-ended inputs, two via stereo RC jacks, one via 3.5mm mini-jack).
Outputs: Two headphone outputs (one via locking ¼-inch phone jack, the other via 4-pin XLR-type jack), one variable-level preamp output (via stereo RCA jacks).
Other controls: two-position master gain switch 
Frequency response: Not specified.
Power output: Class A 5 Wpc @ 50 Ohms
Dimensions (H x W x D): 4.1” x 13” x 12.2”
Weight: ~24 lbs.
Warranty: Not specified.
Price: $1599