1 bit DAC launched by TOPPING

[wwenze]

John E. Johnson Jr has just published a very lengthy review of the D900 on Secrets of Home Theater and High Fidelity.
It's a mixture of subjective and objective, and it's as positive as you might expect it to be.
I suspect that the test results aren't as good as Amir or L7/Fox or SoundStage HiFi or GoldenSound might achieve, but there were no bad surprises.
However he really goes to town on explaining the PSRM technology that Topping use (which most people shy away from).
He also goes into great detail about some of the tests that he performs. It's a good read.

Topping D900 DAC Review - HomeTheaterHifi.com

Topping is a China-based DAC and Headphone Amplifier company that builds and sells direct (from China). Their products are minimalist in...

hometheaterhifi.com

Linear power supply (no wall-wart)

No it's as switching as a Meanwell IRM-20-15

This makes me wonder in how many places and by how many people the word "linear" is misused

That’s why no one builds a full 16-bit thermometer DAC — it would require 65,535 matched resistors or current sources!

Instead, engineers often use segmented DACs, where:

The most significant bits (MSBs) use thermometer coding for linearity.
The least significant bits (LSBs) use binary-weighted R-2R or current scaling.

For example a 20-bit DAC with 2 segments. First segment is a 10-bit DAC where 1 bit = 1.95mV. The second segment is a 10-bit DAC where 1 bit = 1.91uV.