A1:
- Cheaper
- Need separate charging
- Got own volume control, might be confusing having 2 volume controls (on PC/phone and amp)

K1:
- Slightly more expensive
- Charge from PC/phone
- Some phone may need USB HUB (if not enough power), and abit faster phone battery drain
- Since it's a DAC, no separate volume control

Sound-wise, not sure. But beside driving higher-impedance headphones, little to gain sound-wise as modern smartphones already have very good DACs (based on GSMArena reviews).

I believe digital audio, DAC & amp technologies have progressed so far that many smartphones can output excellent audio to headphones. Unless your headphones have high impedance eg HD600/HD800, or your headphones lack sufficient volume, then headphones amp or DAC/amp combo is not necessary.

This kind of setup is laughable sometime ago but it is great today:



http://archimago.blogspot.my/2017/05/measu...sb-dac.html?m=1

This post has been edited by taqu: Apr 4 2018, 10:55 PM

Anyone using this? Encouraging reviews everywhere.

https://www.hidizs.net/products/dac-cable

https://shopee.com.my/Sonata-HD-DAC-Cable-H...9355.1383323863