New style adapter kits are here:
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Just got my DS back from jkrichards. He installed the Lundahls, did the VOCM mod and the C704. Previously had the 4400s and the external LPS through his board. Worth every penny. The highs are much more extended and the bass is more pronounced. With only a week of playing time it may be too early to comment on the soundstage, but everything points to an overall improvement.
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Wow. While I wouldnāt need more bass, more extended highs would be very welcome!
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Could you give me the photo and part information for the 704 application? (with mod)
The photo was posted several weeks ago.
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Ted, did this mean, the C704 mod only makes sense if also the other mods mentioned in you paragraph were done but not without the VOCM mod?
I suspect the bigger difference is the changes in the software. i.e. with the software improving thereās less need for āvoicingā the bass sound. The VCOM will definitely pay off, I suspect more than the C704 mod, but with the better software they are sort of independent changes, but with some synergy when done together.
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I would describe the bass as being more refined and dynamic not more.
I would recommend the installation of C704 with the use of the LL1948.
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I agree with jkrichards in so much as the bass is more articulate, tuneful, not just more bass. Possibly a little deeper.
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Thanks Ted and JK.
Ted, when you speak of SW changes, you mean further Firmware upgrades (which are only available for the Mk II), right?
No, I mean all of the firmware updates from the initial release of the DS. We decided to nuke C704 and to use worse resistors for Vocm based on listening tests of the initial DS code. Now that the code has gotten better, I strongly believe that the original design with good resistors for Vocm and the output filtering of C704 are a better sounding system. Also adding caps on the bottom of the Vocm voltage divider is a good idea.
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It seems to me this R6 mod and the C704 mod together with the Lundahl transformer are the most relevant ones. The details for them are still hard to track down (@dvorak gave me some good hints for the search). The complete VOCM mod seems too difficult for me to find out about to tell it to the modder (I donāt want to leave it to him to choose brand and specs of all the parts but take them from here), but maybe not as important.
Thanks I understand now about the SW changes!
@nicknjan you say highs are more extended and bass is more pronounced - I am definitely seeing volum is waaaaay higher. I used to keep DSvol at 95 and the BHK pre varied. Mostly around 50-60. Some low lwvel DSD higher. I cannot get higher than 45 with some things. Just plain loud and hate to say highs a bit piercing for me. Itās only been 36 hours or so with roon radio running but vol definitely higher. Now the bass yeah itās better. Spot on agree with Nick.
Just curious what others have found.
Well its been awhile after some detours and sidetracks. But debut of the new, hand built Super Supply powering the op amp bit buffers here with +/- 5.5v rails. Since the OA are bi-polar PSU powered now no trafos or blocking caps are required on the output. So that significant sonic impact is eliminated from the equation 
Itās being fed for now by a lab supply, +20V to simulate the DS DAC DC raw rectifier supply out. The same that feeds the main on-board 12V linear. Meanwhile the DS DAC PSU still powers the rest of the board. The next step will be to mount the Super Supply permanent in the case and power it from the DS DAC PSU raw DC out. This DAC1 will be finished then.
Iām using DC/DC converters to step that raw DC down to feed the individual legs of the Super Supply. My first time to use DC/DC for this, but wonāt be the last. Compact, runs cool, reliable, easy. There is other processing and filtering going on to establish the 5.5V outputs. Thereās no noise coming out the Super Supply, thereās massive ultra low impedance energy storage on tap and it is super quiet in operation ~ open loop (mostly) (there are simple shunts to establish the DC set point of each leg), yet the output is ~ immovable (by this load). Basically it is like a tight regulator but with 100x more low impedance, immediate energy on tap. It also employs better than the usual caps of course, eg 4T, the best wire I know of, etc. What weāre shooting for here demands the best.
And weāve been rewarded thusly. It still amazes me how much the OA respond to being fed like this. Stunning clarity out the yazoo, etc. Can hear it immediately. It has exceeded my expectations so am very happy after all this work 
In fact teh OA response to the Super Supply has been so encouraging Iāve ordered a preamp kit of sorts that uses a remote controllable Muses volume control and some very high quality OA circuits. Friend DW in Dallas needs a better pre (to better suit his 30+K speakers 
and weāre going to see how good we can get that and turn it over to him, assuming it can sound good enough. I think it will. Meanwhile here, the open loop proto pre and the proto power amp have also been tweaked a bit further, responding well and are holdinā down the slab and sounding remarkable. After several months of other gear coming through by now, they kill it actually. Version 2 of both are waiting in Spice circuits to be constructed, some day; theyāll be even better
A few related articles (by Bruno P of Purifi and others) have also been inspirational and quite interesting. Weāll see how the pre kit turns out with some super supply added, etcā¦ T
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I have had the same experience with higher volume. The DS is fixed at 94. Before the transformer change I ran the Pass Labs Int25 at 52 to 56. Now, with the same music itās set around 42 to 44. Having only 25 watts in the Pass it is beneficial. The highs were very sharp at first, but have gradually smoothed out with time.
Do you have C704 installed? Do you have the VOCM mod done? If not these are necessary mods to achieve the proper sound otherwise we are comparing apples to oranges. These mods should be done first or at the same time as the transformer swap. The new transformers are way more revealing and will show the deficiency in the DS. (thinner sound) without the mods.
Also the volume of the DS now with the new transformers is the same standard consumer output level as 99% of the DACS on the market if you set the volume to 94 (recommended). The DS in factory form is -3dB from the standard when the volume is set to 100 (not recommended). It needed this boost. You have become accustomed to this non-standard -3dB lower volume.
If you donāt like the extra gain just turn the fixed volume down -6 numbers to 88. It will then be the same output level as before the transformer swap. You could also change the primaries from parallel to series by moving the configuration solder balls from the Pās to the S which I donāt recommend.
The new MKII will have the same standard output level as the DS set with the above settings / mods.
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Yes. And necessary in my opinion. Just do the cap install over (paralleled) the R6, C704 and the LL1948 to get the magical sound. External power supply is the icing on the cake.
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I wish I knew these were needed to get the right sound. next question where the heck in this thread is the best place to find how? Going to have to crack open and find time with friend, again.
EDIT: trying to find where these are in the thread. Cannot search on R6. But found something about a film cap C704 and its very delicate. Does anyone have detailed pics they saved of doing these modes with explanations? Sorry novice here.