This review page is supported in part by the sponsors whose ad banners are displayed below

This is the 26th in a series of reviews dedicated to the concept of 32Ohm Audio as embodied by the store of that name in downtown Portland/Oregon and described here - Ed.

Srajan Ebaen
Financial Interests: click here
Source: Ancient Audio Lektor Prime, Apple iMac 1TB with AIFF files up to 24/192, Weiss DAC2, iPod Classic 160GB, Sieben Technology dock
Headphones: ALO Audio recabled Audez'e LCD-2, Sennheiser HD800, beyerdynamic T1 and AKG K-702; stock audio-technica W5000 and Grado PS-1000; HifiMan HE5LE with optional silver wiring and grill mod
Headphone amps: Trafomatic Audio Head One; Woo Audio Model 5; Burson Audio HA-160; Burson Audio HA-160D [on review]; Meier Audio Corda Concerto; Antelope Audio Zodiac+ [on review]
Cables: Complete loom of ASI Liveline, Furutech GT2 and WireWorld Starlight USB A-to-mini-B cables [on loan], LaCie and Entreq Firewire 800 cables, Entreq USB cable, Black Cat Cable Veloce S/PDIF cable [on loan]
Stands: 2 x ASI HeartSong 3-tier, 2 x ASI HeartSong amp stand
Powerline conditioning: 1 x Walker Audio Velocitor S
Review Component Retail: €999

By May 2010, the headfi community boards were aflutter. Rumors talked of a new headphone from Hifi Man's Fang Bian which would top his previous €599 HE-5LE design. Certain fan boys of Audez'e's competing LCD-2 were highly skeptical, even downright negative. Others applauded greater choice in this "Maggies for headphones" sector. Further early talk fawned over—or ridiculed—the new gold-coated diaphragms. Pricing guesses hovered between $1.300 and $1.600. If true, it would position this design on Sennheiser HD800 and beyer-dynamic T1 turf and exceed the Audez'e. This too polarized reactions. As to the gold, the HE-6 is a planar-magnetic design also called orthodynamic. This requires that the voice coil traces be applied directly to the stretched diaphragm. The lighter the voice coil, the lower the moving mass. Gold can be applied extremely thin—think painter's gold leaf—and won't oxidize. Gold sounds like a very sensible material then.

How about its molecular density? A cubic foot of aluminum weighs 165lb, copper 559lb, silver 655lb and gold 1.206lb. Gold is thus 9 times heavier than aluminum. What's more, its conductivity is lower than that of silver and copper. Audiophile bling then over rational building block? Without knowing the designer's reasons, forum posters could only guess. The backdrop here is that lower moving mass plus higher magnetic field strength are the two axes along which any transducer design must travel to improve sensitivity whilst balancing those gains against diminishing bass performance.

If the gold traces added weight over the company's HE-5LE driver, wouldn't it take more powerful magnets or an even thinner diaphragm film to counteract drive requirements (here planar headphones already are more challenging than most dynamics)? Would the HE-6 be bear to drive? If so, did the world really need another infamous AKG K-1000 which preferred speaker-level power to most dedicated 6.3mm sockets?

An earlier post by the designer did little to assuage the guessers. "The HE-6 prototype needs to see 5 to 6 watts into 60 ohms." Based on a purely resistive calculation, this would equate to an amp rated at 50wpc into 8 ohms to produce 1/10th of that into Fang's load. Many months later, German importer Sieveking Sound advised itchy forum denizens that "an upgraded magnetic structure in the drivers brought the efficiency to about the same as the HE-5 LE. You still need a good and strong headphone amplifier but no longer an amplifier designed for speakers to get the best from an HE-6. A new cable is made from monocrystalline copper which sounds notably better and also turns out to be nicely flexible. A new finish on the ear caps now is a dark metalized paint that looks very luxurious. The same is true for the caps covering the slider mechanism which now sport a silver-colored product identifier. An adapter box drives down the headphone impedance seen by a speaker amplifier to about 9 ohms. It's intended for those who don't want to purchase a dedicated headphone amp."

Formal production replaced the leatherette cladding of the prototype's ear cups with a high-gloss paint.
As to pricing concerns, Sieveking reminded people that "when the HE-5 was first being developed, Fang thought it would be priced around $900-1000 but he was able to get that down to $599 by the time it was released." On concerns about reliability and teething problems, Fang Bian laid out a very condensed company history. "There were many growing pains over the last 4 years. From 2007 to 2008, we were involved in the DIY Jade project. To make that commercial was naive. By 2009, we had made the transition from DIY to professional and released the HE-5. We set up a small workshop to build full-size headphones partly by hand in our own Chinese factory. Unfortunately we had a bad experience with the supplier of our wooden housings. By 2010, the HE-5LE had transitioned to a reliable plastic mold and we now put out a fully professional product on our own production line.

"This finished our Long March and we successfully solved most of our early problems. The HE-5LE, HE-6 and their future brethren will have different drivers but share the same reliable casing. All drivers are tested for more than one year before we release them. This naturally includes the gold drivers in the HE-6. We began our planar headphone project seven years ago. After several hundred sales of HE-5 and HE-5LE units, we've only had three warranty incidents for defective drivers."