Due to family/spacial constraints, I am considering moving to a headphone-based setup in the near future. After some auditioning at a just-opened Hifi storefront (with an emphasis on headphones), I have decided the AKG-K701s are what I'd like to live with. I compared them to Sennheiser 650s, and the source was an iPod with an output impedance of 5 ohms. The K701's spec'd impedance @ 1kHz is 62 ohms, with a sensitivity of 105 dB SPL/V.
So I'm obviously also setting my sights on the Castanet. About the only upgrade I'm considering is to have the output transformer custom wound as a Partial Silver Stranded Secondary by Jack Elliano at Electra-Print. The tradeoff is he cannot wind multiple taps on a PSSS transformer.
So here's my question: if I cannot have both 4- and 8-ohm taps as options, should I compromise with a single 6-ohm tap? Or are any Castanet users already listening through K701s and have a definite preference between the two taps?
Thanks.