It will be a nice experiment for someone that has a passive preamp; I think all passive preamps have resistance in the signal paths especially if the volume controls are potentiometers and should dampen the noise but not totally eliminate it.
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It is impossible to verify compatibility with every piece of equipment out there. This is why they offer the 30 day in home trial. Yes there are other DACS out there that are less demanding of ancillary equipment but none of them sound the same as the mk 2. As great as it sounds with Massive it will get better. Most other DACS out there are what they are and if any improvement is to be had will require hardware changes at a cost, usually substantial to the end user.
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How is it going on the burn in?
Depending on how old that video is, it may by referring to a design element which was pulled at the last minute (they were manually removing components from the analog boards in the shipping beta product run).
As it stands, the digital volume control in the Mk2 is effectively identical to that in the Mk1: after the incoming data has been upsampled to an insanely high sampling frequency with something like 50 bits of resolution, each sample is multiplied by a volume scaling factor of somewhere between -0dB (ie multiply by 1) and -50dB (multiply by 0.00001) prior to being fed into the SDM process for conversion to the final DSD256 output format.
The Mk1 has a switchable analog -20dB attenuator after the transformers. The Mk2 was going to have a multi-level switchable analog attenuator system before the transformers but it turned out those relays had very negative sonic consequences when being fed with ~11MHz signals and the whole system was ditched.
We are told that the audio-band noise floor of the Mk2 without the attenuators is still lower than that of the Mk1 with the -20dB attenuator engaged, which is very relevant for the direct connection to power amps. But separately people have discovered that the ultrasonic noise floor of the DAC (which rises much higher than in the audio band) can interact with some power amplifiers in very audible ways. Putting a pre-amp in between can attenuate the ultrasonic noise and avoid that unwanted interaction.
Now people are waiting for a software update which will alter the characteristics of the ultrasonic noise to hopefully mitigate the problem in direct-connected systems.
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I stoped process for few days when leaved my home. It passed 10 days (240 hours). Sound changed a lot during burn in process, I heard deep and then flat, good separation and then ādirtyā shouty sound on midrange. We will see what happen after 300 hoursā¦
DS mk2 has output transformers. Input impedance of amps are different. Iām sorry for my question because im not technician guy, but difference between DACās output and AMPās input impedance should make frequency response change?
Yes. Ted has frequently advised that for the flattest response you want to use interconnects with minimal capacitance.
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Thank you for the detailed explanation of the digital volume control and the last minute changes that have been done. I was hoping that I can use MK2 with my power amp without a preamp according to Paulās MK2 introduction video. I have a preamp in my system now and the noise issue has been solved but still wish that a future update will mitigate this.
If there is a noise floor issue, Rothwell -20dB Attenuators do a good job between the MK2 and a power amp. Letās the volume setting of the MK2 be raisedā¦ I forget nowā¦ like 20-30 steps or so. Enough to push down the noise issues I had with the previous amp. Now am running Benchmark AHB2ās with the gain knocked down via their switches on the back. If you are not in the UK, then can take a while for delivery from Rothwell. He seems to ship by slow boat. But they get there eventually.
20db would need the volume number to be reduced by about 40. I have the volume at 66 minimum and sometimes go to 100. I could imagine using all of the Mk 2ās volume even though itās a few db louder than a Mk 1. Iām using BHK250s so itās not as though Iām using some super insensitive amps. I need to get to the bottom of this and canāt understand how Paul can say itās quieter than a Mk 1 but lots of people are unhappy. Iām in the UK so canāt try three Mk 2s at the same time (I need three in my active system).
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I took advantage of the recent sale to upgrade my DirectStream DAC to the Mark 2, and it is well worth the money! I had also purchased the AirLens, knowing it would be an upgrade for the Mk1 to use I2S input and is needed for the Mk2. I put it into my system and let it run for several days with intermittent listening. I canāt say I noticed a difference in the sound of the Mk2 over the break in period, but my sonic memory is limited.
After over a week of continuous playing, I decided it was time for comparison with the Mark 1. I used Steely Dan Aja for the bilk of the comparison. Itās my favorite album and I have a 192Hz version that sounds awesome. I like to use the title track to tease out subtle sonic differences because it has great tonality and profound spatial characteristics. I played Aja on the Mk2 to get my baseline and then hooked up my Mk1 (I wanted to use the same cables and power cord.
The change in sound was immediately obvious. The sound stage was smaller and flatter on the Mk1. I couldnāt hear any tonal differences; all the notes seemed to be equally rich on both DACs. But I was able to hear more subtle background instruments, like the triangle used in Aja.
Obviously Iām keeping the Mk2. I bought an AudioQuest Vodka HDMI cable and that was a big difference between the cable they ship with the AirLens. I know many folks say the more expensive cables from AudioQuest are even better, but thatās just too much money for me. I need to replace the motherboard, CPU, and RAMon my gaming rig to better support my new RTX 4090 graphics card.
Thanks for all your posts and shared information that helped me make the right decision.
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Unfortunately without Tedās contribution itās very hard to get reliable insight. It sounds to me like the current swirling noise issue some people are reporting is a complex interaction between the original audio signal, the SDM, and everything in the subsequent analog path resulting in some signal-correlated noise in the upper audible band. Iāve never heard a Mk2 though, just going by reports here.
I can think of three different ways the claim (which was made on this forum but which Iām not going to attempt to locate) that the Mk2 is quieter than the Mk1 could be ātrueā.
- Thereās a subjectively blacker background when used in the PS Audio listening room system.
- The analog noise floor from the DACās own circuitry has been measurably reduced.
- The SDM algorithm is better at shifting 1-bit quantisation noise out of the signalās audio band.
All of those things could be true in general but still leave room for this apparently system-dependent noise to emerge. For now people have to try the DAC for themselves in their systems to see if itās a problem, and for those where it is they must hope that a future modification to the FPGA code can mitigate it.
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I have an AQ Coffee and a Vodka too. Coffee sounded way better than Vodka as a I2S link, and a used one is reasonable priced.
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Thanks dvorak. Iāll just have to try one Mk 2 in the three different situations, i.e. as a bass dac, a mid dac and a treble dac (I hear Mk 1 noise through each of those frequency bands, but the overall noise is easily drowned out by the music when the dac ieither has its volume very high or the recording is very loudly mastered). D.
Just share my bad experience and good solution. I used EU AC cords (different manufacturers) without ground and today plug stock āking cableā with ground. It is much better SQ now!
Wow! Power cords that are not grounded. 
Boy this DAC has been out for a year (I think)
I still have a hard time understanding why things like noise, amp compatibility are still going on.
Maybe itās just me?
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You are correct in saying the DAC has been around for a year already. I was a Beta tester and had mine this early. There is something everyone needs to understand about both versions of the Directstream Senior that makes them different than any other DACS out there. The signal coming out of the units is actually Quad Rate DSD with a filter applied before it leaves the XLR or RCA outputs. It does not have a typical Analog stage. This is what makes them capable of sounding the way they do. The FPGA loads that Ted builds are all in the digital domain and process the signal before it is outputted. I wish everyone had the performance I am getting here in my system but not everyone is using the same equipment as I am. In my system what I get is very natural musical sound without any noise issues. If your ancilliary equipment is bothered by ultrasonic noise than that is a problem. It is all about synergy or lack there of.
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John, I feel the same way you do. I wish everyone was hearing what I do from this DAC. 
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I second that emotion.
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