James, Today I got the chance to listen to the highly thought of HiFiMan HE-6's, which are regarded as possibly the toughest headphones on the planet to drive, when I plugged them into the BP26 headphone out I was surprised at the lack of volume available, totally unusable, would the SP3 headphone out offer similar performance to the BP26 or is it a totally new design which would offer superior performance?
More importantly, I take it the BHA-1 could drive them OK? in the end I used the Schiit Lyr and they sounded pretty awesome, if you haven't already, it maybe worth getting a pair of HE-6's to try.
Thanks.