Phantasy has the potential to sound very good; spritely, limber, and light. If that’s your schtick, Phantasy may be your fantasy. But it is woefully beset by impedance mismatch issues. Many SET amps exhibit the same issues. For that reason, they usually have one, or perhaps two, headphones to which they are perfectly adapted and marketed. The rest is the luck, or ill-luck, of the draw.