As I have found my Virtue 2.2 to be an outstanding amplifier for powering my HE-6, K1000 and K340, all very difficult to drive headphones with conventional headphone amplifiers, the following information may be of interest to other DIY users of this type of headphone. WARNING!!! UNDER NO CIRCUMSTANCES SHOULD YOU ATTEMPT TO USE A 1/4" OR 1/8" STEREO JACK OR PLUG WITH A TRIPATH-BASED AMPLIFIER. THIS WILL CAUSE $$$$$ DAMAGE TO YOUR AMPLIFIER. THE HEADPHONES MUST BE WIRED AS IF THEY ARE SPEAKERS, IN OTHER WORDS, 4 COMPLETELY INDEPENDENT LEADS TO THE AMPLIFIER TAPS. [/]
As Tripath-based amplifiers are not able to safely power headphones utilizing a common ground, it is necessary to "balance" them by wiring them in the manner of speakers, with independent ground returns. The use of XLR connectors makes this a fairly simple operation. Below is the wiring schematics most commonly used for balancing phones using either 3 or 4-pin connectors. While there is no absolute industry standard for this type of connection, the AKG K1000 pretty much sets the standard and is that which is reflected below:
The Neutrik connectors are all numbered by the pins, so it makes them easy to identify. On the 4-pin XLR connector, the basing is as follows:
Pin 1 = L +
Pin 2 = L-
Pin 3 = R+
Pin 4 = R-
If you are facing the front of the female plug (viewing the holes) with the locking notch at the top, numbering is clockwise, with the first hole to the right of the locking notch being #1.
Note that the male is numbered opposite, but when they face each other, the numbers match up.
4 1 = Female connector 1 4 = Male connector
3 2 2 3
On the 3-pin XLR, basing is as follows:
Pin 1 = NC or shield
Pin 2 = Pos
Pin 3 = Neg
The locking notch on the 3-pin XLR is not shown on the diagram, but it is at the top between the 1 and 2 pins. Also, wire color might not be Red and Black.
Although this is not a difficult DIY project, for those who do not feel comfortable with soldering this type of connection, I would be willing to make up an adapter to match a balanced headphone to the Virtue speaker taps.