The astute reader will note the balanced and single-ended headphone outputs have differing behavior based on load. If you spotted that, good catch, pat yourself on the back. The TAURUS output stage has four sections in total. When operating in "STD" mode (the 1/4" jack), two outputs drive each channel in parallel. This results in maximum output current for low impedance headphones, with less voltage swing for high impedance loads. In BAL mode (the 4-pin XLR jack), two sections operate in a bridge-tied load configuration. The result? Much higher voltage swing at the expense of output current being comparatively limited. AURALiC is quick to point out that MOAR POWER is not always the answer. Just because you'd think planar headphones would do best from the 1/4" jack while high impedance Beyerdynamic models should use the balanced output, it doesn't necessarily always work out that way. I'd also add that "limited" output current or voltage swing, in this context, simply means "limited" compared to the max this device is capable of. Realistically the BAL output is still quite powerful into low impedance loads, and the STD output can still swing plenty of voltage. There's really nothing I can think of which the TAURUS can't handle (short of electrostatic models, obviously). Output impedance is low enough not to be a factor—less than 1 ohm from the STD jack, and somewhere between 3 and 4 ohms from the BAL output. Users of multi-driver, balanced armature IEMs may want to avoid the BAL output but all other headphones should be fair game.