Information from Kingwa's web forum, a board admin of the forum visited Kingwa and he compared CD7 and DI-20he as transport, Mac with stock hard drive vs flash drive, and raspberry pi with flash drive and Kingwa's power supply as source.
http://bbs.audio-gd.com/dispbbs.asp?boardid=2&Id=31325&page=1&star=3
http://bbs.audio-gd.com/dispbbs.asp?boardid=2&Id=31325&page=1&star=4
Below, I post the translation of his posts about the impression here, most of them done by google translate and I adjust it a little bit on the translation only:
"Compared with the DI20 of the regenerative power supply, the sound of the CD7 is relatively compressed, and the sound image localization is relatively vague. In summary, the DI20 is like high definition, the CD7 belongs to the standard definition, and the voice of the human voice is obviously two different levels. As for the BNC and HDMI connections, each has its own characteristics."
"The above CD transport and the digital interface comparison, using the same CD to grab the track out of the file. However, Kingwa’s grasp of the track is not using EAC, and the file qualities are slightly lower. I also tried the Raspberry Pi in the same field and found a strange phenomenon. The flash drive does have a great impact on the sound quality. The specific performance is that the same file, Apple laptop's stock hard drive is the best, followed by the flash drive in the Raspberry Pi, the worst is the flash drive in the Apple laptop, the following picture is the Raspberry PI made by Kingwa specifically for his old friends, Pure A DC power supply, you can put the Raspberry Pi motherboard built in, the small board in the upper left corner is the Raspberry Pi. It is said that this power supply is compatible with rock64 board. Although this integrated Raspberry Pi design is not original, according to the experience of the younger brother, the parallel regulated DC power supply is powered by rock64, which is better than Taobao's STUDER linear power supply. Regardless of the convenience of use, the sound quality of Kingwa's power supply is worth looking forward to. In addition, the regenerative version and the normal version of the interface has huge difference , so basically listen to the regenerative version, the younger brother can not help but preach, the user who ordered the regenerative version is not expected to be disappointed."
"First, when the DI20 plays the track, it is similar to the performance of the CD7FV. Second, users who choose DI20HE are very visionary. Third, If this interface and the coaxial output/input are both Audio-gd's products, the coaxial's performance is better than HDMI."