Do you have balanced headphones? If so, which ones?
If not, are you looking at balanced headphones or a balanced amp in the future?
For balanced headphone output, how important is it to have dual three-pin XLRs as well as a 4-pin XLR?
THY FURHOR DEMANDS ZE BEST! BY BEST, HE ZANTS TOP OF PILE BUZZWORDS. 4-PIN!
For a balanced amp, how important is it to also have single-ended outputs?
EXTREMELY. ZE BALANCED AMP SHOULD EMPLOY A BLITZKRIEG OF SINGLE ENDED OUTPUT TO CRUSH ZE FUROR'S SIBLING'S IPOD HEADPHONES!
If single-ended is important, is the quality of the single-ended outputs as important as the balanced outputs, or is this more of a “utility” thing so you can use all kinds of different headphones?
QUANTITY OVER QUALITY. SPREAD ZEM FAR AND WIDE.