I have been using U12 for half a year . I found that it adds smoothness and 3Dness to the presentation , no matter I put it in front of Audio GD NFB 10 SE or Chord Hugo . Typically my experience with Hugo is revealing: direct link to HD USB sounds more precise , quick and accurate , but crisp , glare and digital and somtimes harsh . Comparatively , U12 to Coaxial of Hugo sound more natural and full .
I recently tried putting Elfidelity USB Booster II in front of Hugo instead of U12:
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The idea is simple: separate the power supply of the computer through the USB output and supplying a separate source to it . Although the USB power supply is used by Hugo in its HD USB input only for the purpose of handshake , in practice it affects the sound of the HD USB input significantly . The full potentialof the HD USB input is limited , as Rob had mentioned before , by the EMF and power contamination of the USB power supply .
I found that Elfidelity takes away at most , if not all , of the harshness and digital glare . The fullness of the sound is comparable , or in a sense better and more true than using U 12 . The resulting sound is much more lively , natural , quick and accurate compared with using U12 . For the first time I realized that I achieved the "LP sound" of Hugo described by many admirers of Hugo . In particular , the" timing" of how each note starts , peaks and drops are presented more accurately by Hugo through the HD USB rather than the coaxial port . This is something which Rob mentioned which gave rise to the naturalness of Hugo similar to LP sound, compared with other top DACs .
It has been discussed among Hugo users whether coaxial or HD USB gives better sounding. Each has its weakness and strengths . However with the use of Elfidelity I am convinced that the HD USB port is naturally the better input of Hugo for true reproduction of music .
I found that Elfidelity basically solve the problem and bring the HD USB input of Hugo to a next level, and surpassing the coxial input by a large margin . I also found , strangely , that the power suuply and even the power supply cord to Elfidelity have a significant effect on the sound . I tired attaching the USB charging chord supplied by Elfidelity to a power adapter , direct to a Xiaomi USB power bank, and to an Orico USB Hub . The Orico Hub turns out to be the winner with the most lively ,quick , accurate and full sound.
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