About discrete DSD DAC (part 1)

DSD discrete DAC PCB

The specifications of this DAC board are as follows


The output of the DAC board is filtered by the following circuit board and circuit. The FFT data was taken with this circuit. Of course, this circuit is just an example, and there may be other circuits with even higher characteristics and sound quality.


The following test circuit was used as the power supply for the evaluation. I used an isolated DC/DC converter from MORNSUN Power. The input is 5V. An AC adapter with 2A output should be sufficient.

評価に当たって電源は下記の試験回路を使用しました。MORNSUN Power社の絶縁型DC/DCコンバーターを使用しました。入力は5V。ACアダプタは2A出力で足りるでしょう。

If your DSD signal output board/device does not work well, we offer a USB DDC (digital-to-digital converter), which converts all PCM signals such as WAV and FLAC files into DSD signals for output (details are described separately). Single-rate (44.1kHz/48kHz) PCM signals are converted to so-called DSD64 signals, and PCM signals of higher rates are converted to DSD128 signals for output.The internal operation of DSD transfer in USB is only DoP method, and ASIO DSD is not supported.
DSD signals up to DSD256 are supported for playback. (Since no device driver is attached, Windows supports up to DSD128 (by WASSPI).)
*However, due to the shortage of parts, I can only provide a few new boards at the best of my ability. Therefore, the boards that I can provide are hand-soldered by me (not the number that I can ask PCB assembly companies to provide). If you are an old user of mine, I can rewrite firmware of UDA boards, UDA2 boards, etc. with USB AUDIO CLASS 2.0 data redesigned with recent knowledge at a low price. Please contact me for details.

ご使用のDSD信号出力基板・装置でうまく動作しない場合には、USB AUDIO CLASS2.0によるDDC(ディジタル・ディジタル・コンバーター)を用意しています。WAV fileや FLAC fileなどの PCM信号はすべてDSD信号に変換して出力する基板です(詳細は別途記載します)。シングルレート(44.1kHz/48kHz)のPCM信号はいわゆるDSD64信号に、それ以上のレートのPCM信号はDSD128信号に変換して出力します。USBにおけるDSD転送の内部動作としてはDoP方式のみを採用しており、ASIO DSDには非対応です。
*とは申しましてもこの部品不足の折、新規にご用意できる基板はがんばっても数枚単位です。よって私による手半田品となります(実装業者さんにお願いできる数ではありません)。古くからの私のユーザー様でしたら、UDA基板、UDA2基板等を最近の知見を含めて再設計したUSB AUDIO CLASS2.0データでfirmwareを書き換えるサービスを廉価でご用意しております。別途ご相談ください。


The evaluation set was configured to connect from the USB board to the operational amplifier board using axial pin headers.
If the physical interface with other DSD signal source output boards, such as the USB board for example, does not match, you can make a jig for connection as shown in the picture. The same configuration could be used for connection to a filter/amplifier board.


Example of old USB PCB
Board-to-board connection method

Translated partially with www.DeepL.com/Translator (free version)