I am currently using a Audio-gd nfb 3.1. The information below. I bought a Topping DX7 pro based on the good data in audio science review.com. When I first use it, I can hear the difference immediately. It is more dynamic, bass is more punchy, sound clearer. It sounds great. But after listening for a longer time, I feel a bit fatigued. I can compensate it a bit by switching the tubes in my amp. Then, I need to return the DX7 because the Bluetooth doesn’t work. I plug back in the Audio-gd, and i can confirm it is not fatiguing. It is less dynamic, but also smooth. Now, I am confused on what I should upgrade. Several Audio-gd DACs are reviewed by AudioScienceReview.com and the data is very bad, LoL. I know the bad data doesn’t mean it sound bad, but should I avoid DACs with good data? How should I pick my next DAC? It seems R2R DACs maybe a good choice for me since many people says the sound is more analog-like.
http://www.audio-gd.com/Pro/dac/NFB-2/NFB2EN.htm