DIY ES9018 Hi-end USB DAC

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Although a colleague from Germany had not looked into the topic for a long time, I decided to point to the source of the power problems that caused him to hum in the sound. I figured out the board of this Chinese manufacturer. He has a typical error in power calculations. The transformer actually produces 7 volts of voltage. However, diodes with a very large drop in the forward direction are used in the rectifier. Therefore, the output of the first stabilizer remains a component variable. It goes further to the analog power of the DAC and then to the output.
The problem is solved simply by replacing the diodes with Schottky diodes with a very low voltage drop. This is verified by me in practice.
Probably the correct diodes were used in the prototype. But with a series in China, it is customary to reduce the cost by using cheaper components. In this case, it played a fatal role with sound quality.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.