@wglenn
Thanks for the update, I have arrived back home now and no caps, No worries I have strapped my speakers high and low input together and running only one pair of NC400.
After I had completed A and B testing I left the unmodified pair on the low speaker input. though I have learned disconnecting the unmodified pair sounds best. I should follow that up by saying two unmodified NC400s sounded better in my system than one single pair of NC400 same tone just bigger presentation of the sound heard.
I am finding myself enjoying my music more than ever, so this mod was a big winner for me. expect to hear a change as you did going from mk1 to the mk11 PS Audio DAC and the caps take about the same time to burn in as did in the DAC.
After more hours of burn in I’m hearing single instruments more in the music, the highs are more extended and refined - to me more life like. Vocal tone is more pleasing, closer to the tone as heard when live show. The bass better defined good slam. I cannot hear anything the unmodified NC400 did better than the modified pair.
Regards
John
Sweet! I can’t wait. It makes sense, these are nice little caps. An “audiophile” capacitor does not have to be physically big, per se. The worries over placing a substitute component on the board should be minimized by the short leads and smaller surface area of the cap. Theoretically, the extra lead length could contribute to EMI in the circuit but at this point it would be injected after all the amplification has been done. If this were really a problem with this mod it would sound worse or at least no better, anyway. B-)
I gave thought over this very possibility along time before proceeding, though the benefits featured more so I gave it a shot - I could swap back if the result was not positive. I’m of the opinion the modified NC400 is audibly quieter as I’m distinguishing low level instruments not heard previously or they were masked.
With the improved highs I’m not finding it fatiguing in the least and particularly enjoying music with the delicate sweet highs, again I have not been able to hear this previously 
@johno@datacom.co.nz
Why Ric did not apply all caps change as you did?
That question is best answered by Ric, however my opinion is only those having completed the mod fully can actually comment how the change resulted in their system
Ric said he wasn’t sure if the additional capacitor substitutions would be an enhancement or a detriment and never got around to trying the full replacement. He has now “moved on’” to interest in the Job amplifier, leaving the NCore behind. He does not actually own an NCore and has just made modifications for others and commented on the results. Perhaps if the amp belonged to him he might have felt less conservative in his approach. He was, though, curious about what Johno’s results would be.
My caps have arrived, so hopefully Johno’s are winging across the ocean! :-c
My caps have arrived today in the post, I will give myself three weeks to make the changes and test
Major house renovation commenced three weeks ago and other personal circumstances are delaying my project completion now, my music room is inundated with house hold stuff making it difficult to get to my amp.
I will seek to finish earlier than the three weeks, perhaps wglenn you will finish before I, and I will be very keen to hear how the change has resulted in your system.
Regards,
John
Despite the disruptions in the house I have managed to swap out the caps and removed the speaker mounts on the board and swapped for Silver wire posts same as the already modified pair.
Next couple of days I will reassemble back into the case, so I can enjoy the music, the other changes planed which I spoke of earlier I will do another time its to hard to go with out my music
How are you getting along wglenn
Regards,
John
<fieldset class="gc-fieldset">
<legend> Attached files </legend> <a href="/wp-content/uploads/attachments/59716=2087-048ff4d9a4c2b5f5441ab32c98a7e2.jpg"><img src="/wp-content/uploads/attachments/59716=2087-048ff4d9a4c2b5f5441ab32c98a7e2.jpg" class="gc-images" title="/FileUpload/f0/048ff4d9a4c2b5f5441ab32c98a7e2.jpg" style="max-width:300px" /></a> </fieldset>wglenn I’ve fitted the amps tonight and the NC400’s are running sweet, so much for the three weeks to fit :-)) I’ve been listening for the last couple of hours and very happy two hours in
Cheers
John
Thanks for the great photo John. I’m thinking I will have to take the plunge soon. Heck you steered me right with r41 mod!
Thanks Nile49
The mod clearly makes the music presentation more dynamic, I’m certain the tones are more accurate to the original sounds, I say this based on live performances I recall well. the most noticeable is the highs which are more extended over the stock unit mid range and bass are better defined, the improved extension of the highs is well balanced with the weight of the bass in my system, previously I was wondering about adding sub woofers to my setup however at the moment I’m not feeling I need to do this. I am not saying the mod has added bass it is better defined and I think that impresses on me no need for additional bass extension I like what I hear. I am I big fan of vocal music and the connection to the soul of the performer is improved, the nuances of speech are easily more heard.
Cheers
John
Finished with the NC400’s all the caps have been modified now and the wiring loom installed beneath the amp I may place an aluminium container around the cable which I have not done yet.
picture updated at Ya got a system = you can see the old and new implementation.
http://www.psaudio.com/forum/#/discussion/4109/johno-low-power-music-system
As a result of these changes the SQ is awesome. I have no doubts about saying this - the NC400 are not delivering the quality they are capable of with the stock caps installed
Cheers
John
Congrats! I am hoping to get mine underway this week.
@johno
What the improvments with the 2 news caps compared with only one changed?
Hi fabien44
That’s a good question, however I did not try only a one cap replacement and swapped out three straight away.
my opinion all three best reasons were
1. consistent same caps not a blend of caps
2. all caps foil side facing ground
3. no steel lead caps
If the pneumatic solder sucker did not get all the solder out in one quick session I would wriggle the capacitor while putting heat on the leg of the cap and remove the cap easily.
Then to clean the hole I would get my 9 year old son to help, here I will explain that process = I would have my son hold and have ready the manual solder sucker pump on the upside of the board while I held the NC400 and applied heat to the lower side hole soon as the hole was heated my son fired the solder sucker, my son enjoyed the experience as much as I did :)) this method cleaned the hole beautifully and quickly, very little heat time on the board.
it is required to remove the speaker post at the same time to accommodate all three caps else its to tight a fit.
Cheers
John
Thanks johno for explanations.
Ric mentionned the first to change to get better sound is the change of fuse with Furutech fuses.
What do you think about?
Having swapped fuses in my PS audio DAC mk1 and heard the benefit, I did not hear the standard fuses in the Hypex NC400’s they were swapped out before powering them up, I use HiFi-Tuning Silver supreme. Also I have silver wired direct from the PCB and soldered onto the fuse in the SMPS600
I think this is a good move replacing the stock fuses
Cheers
John
@johno
Something strange for me, why did Ric chose Wima cap which are rather same quality as stock ones? He could have been changed with much more valued caps like Jantzen or Mundorf SIO.
Here a site which recap valued caps:
http://www.humblehomemadehifi.com/Cap.html
I think sound can change but what about new EMI effects on distortion harmonics?
@fabien44
these questions might be best put to Rick directly for his answers
I could only guess the very similar size and the fact that the polypropylene is said to sound better than the polyester material, the nc400 boards themselves are very small footprint and are therefore quite restrictive and what you could locate into the board. And the modified caps - the additional effects of EMI due to the larger surface area I’m not sure. An expensive test tool would be required. I’m not picking up anything I can hear that I would attributed to increased noise in fact the background is quiet, the fact that I can distinguish low-level sounds which I could not hear with stock units is evidence enough for me.
I’m happy with this chosen cap they have improved Highs Mids and Bass, possibly another capacitor would have attributed to sound changes - you would have to test many capacitors to find one that you are happy with. I’m quite happy with these little polypropylene and don’t feel inclined to try any others, I think these polypropylene is a fairly neutral. if you have the NC400 and are willing to try out a few different capacitor options, I would pretty keen to hear about your experience.
Cheers
John
johno said: I could only guess the very similar size and the fact that the polypropylene is said to sound better than the polyester material . . .
This is my guess as well. It is less an issue of "better," than different. The Wima caps may provide a different sound which he prefers.
Wima caps are very good quality, even if they do not have quite the cachet of the specialty lines.