iRiver has recently announced the availability of a new lossless-friendly music player, the Astell & Kern AK100. This portable audio system should be heading to the US starting December 4th, 2012. 
Delivers recording studio quality sound, the Astell & Kern audio player is the first portable hi-fi audio device to have Mastering Quality Sound (MQS) playback. New iRiver AK100 is support for MP3, APE, FLAC, Ogg, WAV, and WMA audio files.
In term of storage, the iRiver Astell & Kern AK100 MQS high-definition portable audio system provides 32GB of onboard memory and expandable via two microSD card slots. As portable, mobile audio system, its 2,000 battery is enough juice device for up to 16 hours of playback.
You can purchase the iRiver’s AK100 audio system for cost $699.
Source
iriver Debuts First High Definition Portable Audio Player in the U.S. under the Astell & Kern brand
iRiver’s AK100 lossless-friendly music player heading to the States December 4th
iRiver AK100 Astell & Kern MQS portable audio player
iRiver AK120 high-end Astell and Kern portable MQS player | GadgetFolder.Com
May 10, 2013 -
[...] iRiver, the famous portable audio manufacture, has launched a new high-end portable MQS (Mastering Quality Sound) player, the Astell and Kern AK120. Aimed to Professional users and audiophiles users, this device promises the finest audio output. New iRiver AK120 is the second player from the company which comes with the elite Astell and Kern brand (its predecessor is the AK100). [...]