anyone heard digital transport?

I have been looking into the Astell & Kern AK 100($700.00USD) and AK 120($1300.00USD). They are portable digital headphone units with internal storage and can have micro SD cards inserted for more content. The AK 120 boasts Dual Wolfson Dacs that can handle all music formats as well as HiRez DSD. The unit can be used as a source for home stereo with a mini to full size RCA cable and as transport from the mini headphone jack with a mini to full size optical cable. A very flexible piece of gear at that.
Think about it you can load all of your music onto a hard drive or iTunes, and transfer it to a number of micro SD cards that will play as a portable headphone player, optical digital transport and as a source for listening on a home system. All of this can fit in your pocket! Also the digital signal is extremely clean and rivals many super high end transports.

http://www.astellnkern.com/

I touched AK120 several month before, as I konw ,it is not the best sound because it made by DSP. And I know some production like QLS350 use singalchip microcontroller, that structrue can reach better effect.

Bird_9527

I took a look at the QLS350-V2 and it seems to be very similar to the AK 100 at less than half the cost. There are some pluses and minuses to each unit, but for me sound quality is most important.
You have stated that the QLS350-V2 sounds better than the AK120, but how does the QLS350-V2 compare as a transport to a DAC?

My main purpose for this type of player is the digital outputs. As we all know the digital signal can be degraded from many external interferences as well as internal. With music ripped to WAV and transferred to an SD card I'm assuming the transfers are bit perfect?

I have and extensive CD music collection and the thought of putting it all on a hard drive and transferring to an SD card with the ability to bypass USB interface issues that can degrade sound, with a very clean power supply, is very interesting to me.