Yes my DS MKI DS2. Maybe I should have been clearer. My DS MKI DS#2. This is the modding DS topic not the modding the MKII topic.
We have not even received our MKII yet. We are only planning to do our transformer replacement as Ted has already updated everything.
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Thanks Jeff. I was pretty sure I was confused. 
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I will also change the 6800 again against the 8200 or the 10000. Did you hear noticable difference in top highs from 6800 to 7500? I think about trying the 8200 first.
Will be perfect at the end, it just needs the right choice.
You must understand that in mods we have one serious difference - AD1839, it has a completely different sound signature compared to AD1832. And when I had LL1948 with AD1832, I used 15nF on the C704 and did not conduct such experiments. And with AD1839, when changing the value of C704, the supply of not only HF but also LF changed. The closer to 15nF, the richer the bass and the slightly noticeable weakening of the āairā at the high frequencies, but at the same time they are more prominent and weighty.
Thanks I see, then I make my own experiment and will see how many further trials I need 
You should use caution with the solder pads for C704. Repeatedly changing values will eventually ruin the solder pads as they will start to lift.
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Thanks, yes, it should better be just one more try. I already thought about trying caps in a adapter plug, but then Iād have to know what values to take while one is already in and between which pinsā¦
I still think about which to use 8200 or 10000. On the one Hand the 8200 will already remove the rise over flat and make the FR go down over 20k and not up from 15 to more than 20 (which might be what I need), on the other hand 10000 will be a bigger step necessary between 6800 and 15000, which was too muchā¦
Are there any modās that can be done to the Stellar Strata?
Any part of it at all?
I tried a frequency track CD on the speakers today, itās interesting. Up to 15,5 kHz I hear clearly, 16 kHz very low and need to go to the chassis, then up to 17,5 kHz is rather imagitation or nothing (more probable) and above that itās gone.
Whatās interesting is, that with my AMT tweeter frequencies over 15 kHz are very dispersion sensitive vertically.
So the 15nF going down 1,5dB between 5-20k has its effect, thatās clear.
You donāt have frequency plots over 7800pF for the Lundahl, right?
The main quest is: which influence does FR around 20kHz (which we donāt hear) and above have towards frequencies belowā¦
Correct. We did not do more plots because itās not necessary. The 6.8nF or 7.8nF will both be optimal. I feel you are overthinking this whole thing. There are way more things to improvement to the sound quality then changing the final filter value 1nF.
For instance the DC offset feeding the transformers is way more important and will effect the sound quality way more then what you are chasing.
Yuriy Is doing the correct things. Changing the opamps is probably the best thing to do to improve the sound quality here. Very low DC offset and distortion however is very difficult and only proās should attempt. A transformer that is designed specifically for this application and can do away with C704 I feel would be better. The LL1948 is a good transformer however it turns out may not be the best choice here as it needs the final filter to correct the ringing the transformer has in this circuit however together will work.
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Itās not overthinking just for the will to optimize what needs no optimization, Itās that the 15nF cuts the top end and the 6800 pF sounds artificial on recordings with very open top end. I just look for the right choice as the best compromise and I have no other choice than to decide between the 10nF which is a little more towards the middle or the 8200pF which is the flattest up to 20k and not rising above that.
I didnāt expect the differences between 6800 and 15000 to be so big. Whatever I decide for, dropping the 15000 for a lower,value made an unbelievable improvement to most every recording and together with the VOCMās improvement in bass (and surely also the transformer performance etc.itās a game changer in terms of open, airy, transparent 3D panorama, Iām still puzzled and newly listen through my library for days now.
Yes we standard mortals reach a certain end of options and Iām sure your new transformer is even better, but the right choice of cap for the LL1948 will already be magic enough for most I guess.
Agree.
Yesterday I was wondering why the 12V regulator in my DS has run hot since I installed ether the LL1948 or the new nickel transformers. Asked my son if he had any ideas. Well it turns out that running a 1:2 transformer gives you more gain however at the cost of drawing more power (heat). Before I did this mod I could not keep my fingers on the heatsink. Now, with the heat spreader I can keep them on all day long.
If you are running a 1:2 transformer with a stock power supply (no external supply) you should do something similar.
Just gently spread the heatsinks slightly apart and slide the heatsink pad (for a M.2) it between the heatsinks. I held the heatsinks together with a U shaped metal spring wire I made up.
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Didnāt somebody do a little instructions for VOCM mod? Is it in here somewhere and importantly, up to date? I looked for a long time yesterday. I need to be clear on VOCM parts required and how to get them, before I can commit to new transformers. Thank you.
I suggest performing the following Google search:
site:psaudio.com vocm
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I had the same problem and after the help of the guys here I started to see through.
If you begin with my following post and consider the few questions and answers that came after it, you should have the basic understandingā¦
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Thanks JK, but can you explain the idea behind it?
Is the intention that it works as an additional heat transmission surface?
Any you use the metal spring just in order not to damage the board by the sinks slightly moving apart?
In my case (Bridge installed) the other heat sinks are much hotter than the two in front.
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