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.
Consider this headphone amp if:
Look further if:
Ratings (relative to comparably priced headphone amps):
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.
HiFiMAN EF-6 Headphone Amp/Preamp
Type: Class A solid-state headphone amplifier/preamplifier
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.