I've recently reviewed most of the contenders for the world's best headphones: the Audio Technica ATH-W5000, Denon AH-D7000, Sennheiser HD 800, Grado PS-1000, Ultrasone Edition 8, and the best headphones I've heard so far, the Stax electrostatic SR-007Mk2. I listened to the Stax with the Woo Audio WES headphone amplifier. If you want and can afford the best, go for the Stax-Woo combination.
But now I have yet another headphone to check out, and this one is a very different-sounding design. Oh, and it's less than half the price of the least expensive of those models!
It's called the Hifiman HE-5, and it uses planar-magnetic drivers to create sound. A planar magnetic driver is a large, flat Mylar diaphragm, coated with superthin aluminum, suspended between rows of slender bar magnets. The HE-5's diaphragm is therefore driven over its entire area, which dramatically reduces distortion; conventional dynamic headphone drivers are "driven" by a voice coil on the outer edge of the diaphragm, so the inner portion is more likely to distort.
The HE-5's driver is similar to the Stax electrostatic 'phones in that way, but the HE-5 doesn't use the bias charging scheme that all electrostatic headphones use, which also means the HE-5 can be used with standard headphone amplifiers. The Stax cannot.
The HE-5 is incredibly detailed sounding, but at the same time it's very smooth and laid back. Swapping between the HE-5 and the Sennheiser HD 800--considered by many to be the world's best dynamic headphone--the two headphones are opposites. The HD 800 is brighter, crisper, with more apparent treble detail; the HE-5 is softer, warmer, and more natural-sounding.
This is especially obvious when listening to acoustic music; the HD 800, as good as it is, sounds like hi-fi reproduction, while the HE-5 sounds real. That's especially true for vocals; I have never heard more lifelike reproduction of the sound of a human voice as I did from the HE-5. I attribute most of that to the headphones' superlow distortion, but there's more going on. Other dynamic headphones constrict and flatten voices.
Bass? Yeah, the HE-5s do bass. Listen to the way they pound out the thundering drums on Grizzly Bear's "Veckatimest" CD. Definition and bass "air" are also well above par.
The HE-5's soft, cloth-covered earpads feel nice, and the headphone is fairly comfortable. But it's relatively heavy; remember, there are lots of magnets in the real walnut earcups.
The HE-5's headphone cable is removable and therefore user replaceable; the silver-plated copper cable is very thin, but fairly stiff. The 6.3mm plug and housing feel nice and solid.
I love the HE-5, but there are a few qualifiers to consider. First, the HE-5 is a bear to drive, so it won't work on iPods or most portable devices. I used dedicated vacuum-tube headphone amplifiers, the $399 Hifiman EF5, and my Woo Audio WA6 Special Edition amp for most of my listening tests. So sure, you may have to add the cost of a good amp to the price of the HE-5 (but the HE-5 was also pretty amazing plugged into my Onkyo TX-SR805 receiver).
The HE-5 isn't perfect, the Grado PS-1000 is more dynamic, and the Ultrasone Edition 8 makes a lot more bass. But there's something about the way the HE-5 combines remarkable sweetness and effortless detail that I find irresistible. They are my new reference dynamic headphones.
The HE-5 headphones are available from Head-Direct for $599, and with the EF5 amp for $899. In any case, they're a whole lot cheaper than the best Grado, Sennheiser, Stax, or Ultrasone headphones.