Modding the PS Audio Directstream DAC MK1 and MK2

I would like to continue discussing all the mods we have created for these two DAC's as it seems PS Audio is no longer allowing discussions about them on their forum.

For reference here is a link to the closed discussion.


I did not see the 8/22 post about the Direct Stream "Junior" model; so, my bad.

Here is a FFT plot of the MK2 with the new Massive firmware.  Note the distortion is worse than with the last firmware.  This new massive firmware is almost impossible to measure the actual noise floor.

MK2 with Massive FW:


The MK1 has better measurements. Note the better dynamic range and lower noise floor of the MK1.  Note this one has a bad transformer on the right channel.

Not to trivialize noise measurements, but this sort of does show how there is not a 1:1 of noise and Sound quality.  Now that being said there are few reports of some amps this causing issues with, but that is a known factor and reported in the Stereophile mag.  

I for one love the SQ in my setup, could care less on the measurements. I have a scheduled appt. to put in my APS transformers from JK next week.  Going to let burn in while away for a few days I am out of the house. Hope it does not bother the rest at home.  But I should get 250+ hours burn in with them.  

Posted on other site.

Not sure why someone would want to bad mouth PSA so much except for profit or just to be mean. Life is too short for that kind of shtuff.

Also without PSA his transformer business would be non existent so need to be careful before shooting oneself in the foot.


What makes him think I’m badmouthing PS Audio??? I was asked by Elk, the moderator on that site to post these measurements. That’s all I did was post actual unbiased measurements of both the MK1 and MK2.