Asakurai
100+ Head-Fier
how is your first impression? interested too, especially in the BU2
I own a few good source such as: Quloos QA390, YinLuMei A1S, BLKEJI L2, F.Audio FA2, KAEI DAC-1 Pro
Let's talk about BU2
build quality is great, easy to use, Bluetooth connection is better than I expected (more stable than YLM B2 for sure) and it does support APTX HD
Reference-neutral sound tuning with slight boost on upper treble which result on more airy presentation with good detail, best pair with warm cans.
Noise floor is good so you can use your hyper sensitive IEMs safely, the power is okay, it can drive your planar through balanced but it won't drive to maximum potential for some "hard-to-drive" headphones.
The Value?
For $299, BU2 has decent value, you get what you paid, I don't think the value is phenomenal since YLM B2 also has similar value at the price range.
SQ alone, I think it's better than DX160, better noise floor, and it's definitely more neutral than DX160