Last weekend I was able to attend one day of the Rocky Mountain Audio Fest, which is held here in the Denver Tech Center, not far from me, along with fellow MacinTech members Rick Hyman and Jon Flowers.
I went through many of the vendor displays in the “CanJam” exhibit focused on Headphones and mobile/personal audio devices, and one of the most interesting things for me was from the Sennheiser booth. I have a set of Sennheiser HD600, which they had on display along with an HDVD 800, their $2,200 headphone amp, as well as an HD650, an HD800 and HD800S. What I noticed is that they were using balanced cables for all of them, where there are separate ground wires for each side, along with isolated, balanced amplifier modules.
Even in the noisy exhibit tent, all three of us could hear a marked difference between their demo units and my headphones, which I had brought with me. Even with the same model headphones plugged into the same amp, but with the standard cable using a shared ground, there was a noticeable improvement in the clarity in the high-end, better control in the bass, and a more open “sound stage” with the balanced cable.
Because the HD600 has a replaceable cable, it’s easy to upgrade to a four-wire balanced cable, and I found an “inexpensive” one from ZY for about $75 through Amazon.com. Sennheiser’s balanced cable is about $240, and “premium” cables go for about $330, which is more than I paid for the headphones!
To use balanced headphones, though, you also need a balanced headphone amplifier. There were lots of options on display at RMAF, either solid-state or tubes, but most of them were in the $4-7K range! One of the exhibitors, though, was Schiit, an American company that is making high-quality gear at more affordable prices. They have recently introduced a headphone amplifier with a built-in Digital/Analog Converter (DAC) module that is upgradeable, the Jotunheim, which sells for under $500! I was able to listen to it at the CanJam event, and was impressed enough that I ordered one from their website that night.
While I was anxious to try out the new amp when it arrived a couple of days ago, I started by playing the Sound Liaison recording of "The Old Man and the Sea" by BATIK through my existing portable DAC/amp, Teac HA-P50, and the original three-wire cable on the HD600. It sounded good, but didn't have the sparkle that I heard at RMAF. Next, I plugged the HD600 into the Jotunheim with 1/4" adaptor, and listened to the same track through the Jotunheim, but still with the standard three-wire cable. With the Jotunheim, both the bass and high-end were noticeably improved, and the sound was more detailed and had more dynamic punch. Finally, I opened up the ZY balanced cable, and carefully unplugged the stock cable from the HD600, and connected the balanced cable in its place. The ZY cable seems to be well made, with a Neutrik 4-pin male XLR connector, and nicely molded connectors for the Sennheiser headphones. The cable has a braided nylon jacket, with a shrink-wrap sleeve over the "Y" where the cables split for each earpiece. I plugged the XLR connector into the balanced jack on the Jotunheim, and restarted the same track again... This was another order of magnitude of improved clarity in the high-end, more solid and controlled bass, and a wider, more open sound stage.
Between the Jotunheim and balanced cable, the HD600 sounds like a completely different set of headphones. While I can't do side-by-side comparisons like I did at RMAF, I can tell that each step exposed more detail in the sound than I had been able to hear previously. I would have to believe that the people who criticize the Sennheisers as having a "veiled high-end" and lacking bass simply aren't driving them properly. With a decent balanced headphone amplified and balanced cable, the HD600 really comes to life. Considering that compared to most of the available audiophile offerings, this entire setup has cost less than $1,000, which would be considered pretty entry level, I feel like its delivering a pretty amazing audio experience.