I recently had Steve Sank of Talking Dog Transducer Co (Tucson), go completely through my Kora Hermes DAC installing Nichicon's best Muse KZ capacitors with higher values of course and some top grade Audiocap film caps (theta as per my request). He also rewired my Kora Hermes DAC so I can flip a switch and choose between 12AU7 or 6DJ8 tubes. (I prefer the Amperex 12AU7 myself by the way post mod). And among other things, he also put in some superior oxygen free wiring to replace the original Kora cheesy copper wiring, and some gold over copper RCAs and a new better input switch as the original Kora's switch had fallen apart on me.
I was a little concerned, messing with the original caps. However, my only regret is not having done the mods sooner. What I hear is absolutely wonderful sound, heads above even the original Kora sound. Absolutely exquisite.
The sound stage has expanded dramatically. Instruments just float in acoustic space. There is now a 3D depth to the music that was not there before. The mids are more organic, yet still rich, vibrant, and open. The highs and bass are much improved also. The original Kora had just a little bit of glare in the upper mid-range and that is now gone. Yet there is a nice shimmer and extension and a almost glowing vibrancy and clarity in the mids and highs that I didn't hear before. I just want to sit and listen to almost everything that plays through it.
FYI, the Nichicon Muse KZ caps which replaced the aging Phillips caps aside from sounding wonderful are ultra reliable. Joule puts them in some of their $4,000 plus components (I had one, the modified Kora sounds better to me). My modified Kora Hermes DAC will probably outlive me and then some. And it will have to because this DAC is not for sale. After trying over a dozen different DACs on the market, I have finally found one that I can die happy with.
Steve deserves some credits: I think he is a gifted designer and modifier of both tube and solid state gear. His father worked with RCA in development and Steve has 35 years of experience starting from there designing and modifying equipment. His insight and work shows it.