AT A GLANCE
Supports lossless formats
Great-sounding headphone out
May be used as standalone DAC with a PC
Rudimentary touchscreen DAC use limited to 96-kHz or lesser files.
The AK100 successfully ventures beyond the iTunes universe to open a world of high-resolution portable playback.
Is Apple the biggest obstacle to progress in portable audio? The iPod has been around a full dozen years, and the iPhone for half that, yet even today the Apple ecosystem fails to support 24-bit audio file formats. All Apple-supported file formats&mdash;even the best of them, Apple Lossless, AIFF, and WAV&mdash;are limited in iOS to 16 bits. That’s not high rez, that’s mid rez. Forget about playing your growing library of 24-bit FLACs. Leaving the Apple ecosystem can be painful because the company’s touchscreen and clickwheel devices are so ingratiating. But leave you must if you want better sound in your pocket, and the Astell & Kern AK100 may be on your list of destinations.