JK Richards PS Audio DSD MKI transformer upgrade


I sent my PS Audio DSD MKI to JK Richards to be fitted with the upgraded nickel transformers and VOCM caps. Should be arriving today. Will follow up with a comparison review  once the upgraded DAC settles in. 

Here is a link to the lengthy thread covering the evolution of the PS Audio DSD mods.

https://forum.psaudio.com/t/modding-the-directstream-dac-mki/2680

gme109

For the ones who has a Directstream MK2 with our transformers installed. We have a firmware that makes a large improvement in the sound quality.  Much more detail and a more realistic sound stage.

Download and unzip it to a USB thumb drive. The file name will be fpga1_228_APSaudio.bin  Note: you can unzip this file in your current USB thumb drive that contains the Mount Blue Sky fpga firmware if you want.  That's what we do so you can select ether the blue sky or this new fpga file.

Download here

Insert the USB thumb drive in the DAC.

Go to the system menu (long press the menu button)(right button till you see system)(right button til you see load firmware)(enter)(scroll down till you see fpga1_228_APSaudio. Enter to load. Reboot.

In the menu info screen the fpga firmware will show as 228_massive

Give it a try and let us know what you think.

You can always go back to Mount Blue Sky fpga just load that firmware in the load firmware section instead f the new one.

This is just the fpga firmware and not the newest user interface firmware that blue sky firmware from PS Audio installed. 

We have come a long way in fixing the distortion and noise issues in these MK1 DAC’s

Here are the original distortion figures.

 

Here are the FFT of the corrected Limited Edition MK1.

We achieved this by adding snubbers in the correct places.

Approximately a year ago, we began incorporating snubbers into the power supply of the Limited Edition. This significantly reduced the noise floor. This method has not been used in these MK1's previously; however, it made a significant impact, prompting us to conduct R&D on this process for the MK2, where we are seeing considerable success. Further updates will follow shortly...  

Look what happens when you have high (over 2mv) DC offset feeding the transformers.