Modding the PS Audio Directstream DAC MK1 and MK2

Yes they are different. The Edcor XS 4400 has 4 windings that can be configured in several ways. (4-center tapped coils. 2- primary and 2 secondary). PS audio just uses the two secondary coils in series without using the center taps. They use the series junction as the center tap. The Edcore is a cheap ($30.00) off the shelf transformer that can accommodate many devices. These Edcor transformers were not designed to do this however it seems to work however with a great loss. Ours are designed specifically for the MK2 or the MK1. That’s why they sound so good. Our transformers designed for the MK2 will not damage the analog board whatsoever as PS Audio is claiming in the link above. It’s impossible unless the technician does it improperly. We have been running our MK2’s continuously for a year now with no issues. We have many customers doing the same also with no issues. Our extensive testing using state of the art equipment shows better performance using APS transformers unlike the statements in the link above.  Using a properly installed APS Audio nickel transformer will NOT damage the board however an off the shelf transformer can as it would not have the correct wiring. This is a passive device that improves the sound quality of the MK2 by a large amount just like the ones designed for the MK1 which are a different design

This is so ridiculous as PS Audio contacted us and wanted us to license or sell them our transformers. I can post emails from them if necessary.

Here is the real culprit of failing analog boards in the PS Audio MK2 units.

Hack job hand soldered adapter boards being installed at PS Audio. Guess they ran of the proper parts so they hacked this in instead. If I paid the kind of money these units cost and found this I would be very upset.

Shall we say more?

OOF. Yeah I installed my MK2 APS transformers without any issues. Luckily I don't see that random PCB sticking out from my pictures of when I opened up my unit.

If install properly you will not have any issues whatsoever. It’s realy not hard to install with the proper equipment. Pull old transformers and re-solder in the new ones in the same footprint where the old ones came out. No adapter boards or hack job needed.

Installing components like in the photos above is a sure way of making a unit fail. Drag soldering this type of package is a big no no in a production unit. It’s OK for prototyping however should never be used in a customers unit. Did they think no one would ever see this?

Because of the statements made by PS Audio about performance, We will be posting actual measurements of a stock unit vs a unit with APS transformers.We have already posted measurements with the APS transformers installed using the last massive firmware.  That in-house testing screenshot they posted is showing useless information as there is no actual data just a pass / fail. What are the actual measurements? We will soon see.

Quote from driftingbunnies

"Luckily I don’t see that random PCB sticking out from my pictures of when I opened up my unit".

If anyone opens up their unit and see’s this just put it back together and ask for a replacement unit. It will eventually fail without any help.

Today a PS Audio technical service technician posted an advisory regarding modified DSD Mk II DACs (latest iteration).  Apparently they have had more than a few of these modified units come i for repair. The nature of the repair was an output transformer swap.  PS Audio is not saying what transformers were installed, who did the install, or if the installation was sub par.  These units are failing all PS Audio bench tests and the repair is a replacement bard with the original style transformers installed.  As the affected units have been modified the repair is not covered buy warranty.  A link to the thread provided in the PS Audio Forum is provided for reference: 

https://forum.psaudio.com/t/dsd-mk2-aftermarket-modifications/36378