thank you. most appreciated. will upgrade the fuse and the transformers together.
Thanks Serhan, I was leaning towards outsourcing, but my thriftiness was kicking in. Now I really should just play it safe. If anyone has recommendations on how to pack a circuit board to survive the apocalypse, i.e., any shipping company, let me know.
Use a ststic wrist strap during disassembly, a static free bag and bubble wrap tight into whatever box you choose.
If you are in the USA itās pretty hard to beat USPS packages and service.
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Can you tell something about the SQ improvement it made?
I did the NCF modification.
Struggle a litle installing the lower bolt.
Thx again
I find Orange fuses thin the sound out. Purples donāt do this. The lower mid and bass are fuller, so the upper mid is no longer forward, giving a richer, smooth sound, all with added detail.
They do take a whole month to break in though, sounding thin to start off with, then the bass suddenly comes after about 2 weeks, but the top is closed in (too much filtering effect) then all balances out after 4 weeks.
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good to know, now Iām glad I bought the purple.
@Turbotk
Hi Todd,
Thank you for offering to help.
Well by now weāve had no transformers in it- really nice, but now need some caps too since the design is 1 pole supply, which brings issues of their own. After that, then went back to transformer output stage but with some shielded high nickel core transformers (better than the M6 steel, less veiled).
-Now some shielded amorphous core transformers are in there. Felt obligated to try it as we are looking for the best we can achieve.
Along with some ~ substantial additions to the local PSUās of the op-amps (x8), the op-amp supply regs (x2) AND, Iām thinking and assuming importantly, the 5v supply for the device that slings the actual DSD bits into the maw of the op amp array. To my thinking that also merits an analog supply treatment basically. After some pondering, seems the analog PSUās need help IMO. I think its responsible for the somewhat lightweight sound overall stock; thatās readily apparent to me as I swap in various other DACās into the system (Terminator, Venus, Pontus, etc) during the course of my NA service side job.
Iāve been trying to decide how much (if any) bypassing or perhaps even beefing up the CM feedback voltage divider node needs for each op amp. Seems to me that node should probably NOT move a uV while playingā¦ Right now all I have are some small PPS film caps to VSS on that node. Hmm.
Oh, and a hand built magnet metal shield around the whole analog section basically, importantly shielding from the digital board that lies directly above.
Whewā¦ but ok, NOW weāre talkināā¦ Ahhh, yesā¦ It plays low bass now and there is ~ proper weight to the sound. Thereās amazing clarity and lack of distortion, helped greatly by the PSU updates IMO and the low distortion core transformer output stage. I can sit and listen to it playing ~ quietly, entering an almost trance-like state 
Even better of course that itās feeding a good analog system that is (usually) passive bi-amped as well, into Concept 500ās (extremely transparent). Passive bi-amping generally brings a large reduction in IMD to the table; basically we only know how much is there when we can hear it reduced. It can be quite eye opening.
Iām feeling so blessed
T
I did the 3M shielding on the bottom of the digital board as well as the top of the digital chips however I ended up removing the 3M shielding that was placed over the two transformers because it removed some high end and messed with separation. The magic I was used to hearing was gone. As soon as I removed the two pieces the magic was back and sound restored. I would NOT recommend placing the 3M shielding over the transformers. Maybe Stillpoints paper is different???
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Thank you @jkrichards for sharing your experience.
If you donāt mind me asking, how does the final result compare to absorber material on chips only?
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I did the 3M on everything at once so I can only comment on the removal of the transformer pieces. The shielding I left in place made a very small improvement however it did slightly improved staging.
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Thanks for sharing. I have not done the bottom of the digital board, but did the rest. In my case, I can confirm better sound stage and lower end.
@ Serhan & jkrichards
I did the shielding mod a long time ago and in my experience the impact was subtle.
The impact of removing the bridge and using the Antipodes CX as a streaming device was significant.
The transformer upgrade was a big step forward (a new dac).
Maybe i noticed not a big impact because the sequence of the mods was different.
Did you also shielded the flatcables?
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Hi @adimon ,
I added network isolation (Melco S100 and Adot) which allowed the removal of Matrix in favour of Bridge. I believe the biggest differentiator in my case was the addition of the 3M absorption to bridge and the display card.
I have not treated any cables, yet! I have no flat cable either.
Edit: oh my, My mind wandered to ribbon speaker cables rather than the two ribbon cables in the DAC 
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One must be careful shielding ribbon cables as it can change impedance / capacitance of the cable which in this application is a bad thing. I did not and would not recommend shielding ribbon cables. I shielded the bottom of the digital board, the digital chips (NOT THE SMALL INDUCTORS) and the display board only.
I did this after all other mods were done and listened for a couple months before this shielding mod.
I used this AB6005S 3M Electronic Specialty
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As soon as I have time to remove the cover of the DS Iāll verify.
I use Stillpoints (which might be different than 3M) and just detected improvement with every measure applied, but didnāt check each single one separately so far.
Thanks for sharing your experience,edit: i see now you posted it was the thinner one. Like I used.
Which version of 3M was on the transformers. That The AB7050HF or the Thinner AB6005S did you apply on your output transformers? I do know the thicker one has more affect near transformers during temp placement and takes a bit of tweaking to place it. Had you completely wrapped the transformers?
i used the thinner one. With foil layer and far less absorber and placed it also on underside of the digital board. On the ribbon cables I only covered IC directly under the ribbon cables. Like you recommended above.
https://www.mouser.com/datasheet/2/1/EMI%20Absorber%20AB6000%20Series%20TDS-475854.pdf
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I just remember Ted mentioned that the paper should be effective down to the 10 MHz range for some of the chips. The Stillpoints ERS is and some (but not all) of the 3M, too. I guess this should be considered.
ERS shielding effectiveness (in db attenuation):
10 Mhz - 49
100 Mhz - 48
200 Mhz - 62
400 Mhz - 53
800 Mhz - 54
900 Mhz - 50
1 Ghz - 49
2.4 Ghz - 53 (802.11B)
3.5 Ghz - 54
5.8 Ghz - 57 (902.11A)
7.5 Ghz - 61
10 Ghz - 66
17 Ghz - 55
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