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Back to our own scenario, another hint was changing the split file size setting to a higher value. Once set, the plops and ticks were mostly eradicated. This parameter thus allows for some fine-tuning. More disturbing was the thin sound which hadn't changed. It was as though the DAC hadn't been properly burned in. To make sure it was, we looped a burn-in track for 10 days of non-stop silent action. Afterwards the sound was much better but not yet at the level we expected. Whilst listening to another system we gave the NOS1 another 10 days of forced labor. All along we had intensive e-mail contact with Peter. Our intention was to play consumer as much as possible and figure things out by ourselves. Peter is not really short in emails and re-reading is recommended. A big issue was the cabling. Here Peter’s notion was that an audiophile cable can make things better because it filters out something that's wrong in the first place. An even bigger issue could be the AC ground as suggested in his post. All this resulted in us spending lots of time on hands and knees whilst rerouting power cords. After many days of trial and more errors of audible ticks, complete freezes or plain wrong sound, we were on the brink of throwing in the towel. Then Eureka struck.

Wallpaper when no specific cover art is available in the album’s folder.

It all came down to connecting PC and DAC into a dedicated non-grounded wall outlet. The Power Plant too connected to a non-earthed outlet and from there the power amps got juice via a passive Furutech power bar. The speaker’s woofer amps were fed from another shared zone in the Power Plant. Along the way we learned that even a powered-down but still connected component influences the sound. The biggest lesson learnt was to never leave an unused piece of equipment plugged in and equally important, to never leave an idle cable plugged in either as it becomes an antenna, shielded or not. Finally our eerie 8kHz tone was gone. Now we had the sound Peter spoke about. With some fine-tuning it improved even further. So what is that sound? As close to ‘live’ as we've heard. Playback is amazingly fast with rise and fall times. Every detail captured by a recording gets a chance to be heard. This results in very ‘real’ cymbals even when they're only slightly tickled at the bell with a nylon or wooden tip. Yes, that difference is clearly evident. Lack of noise which otherwise covers up all immanent beauty even in nowadays oft-reviled 16/44.1 recordings revives these same tracks.


In the earlier photography analogy, we'd mentioned how blurring parts of a picture make a scene look like a miniature. Using that same analogy, the XXHighEnd/NOS1 DAC combination is the unique tool which undoes this miniaturization effect. Music played over this team scales things back to their proper proportions. This includes not merely physical size but timing and tonality. It's hard to describe this sound in audiophile terminology as discrete frequency bands cannot be singled out. The whole is the whole and not any sum of distinguishable parts. Individual instruments and voices are followed easily as the scene cast into the room is stable and devoid of any blur. To us the most hideous instrument in a symphony orchestra is the triangle with its piercingly high-pitched tone and numerous overtones. Now it became much more than just piercing noise. It had warmth and gradation even over the short period it lasted. And none of it came at the price of clinical artificial enhancements. To the contrary, emotional content was preserved and thus shared with us as listeners. This is what being 1:1 bit perfect can really be. Even at very low volume settings—in our case 54dB down—the complete aural spectrum remained alive including bass slam. These findings were made with what Peter calls the emotional engine #4. Listening to engine #3, things got more analytic and less involving. We finally grasped what he'd been trying to tell us all along. His sound quality has deeper meaning than Wikipedia's "assessment of the accuracy, enjoyability or intelligibility of audio output from an electronic device". It boils down to getting rid of all negative influences which in 99.9% of all cases seem to be the result of noise which blurs the picture.

Wallpaper when cover art us found in the album’s folder.

There's a downside however. Reverting to CD playback even with what we thought to be our best available hardware became distasteful once the Dutch combination had been optimized and experienced in full. By comparison the sound of spinning CD lacked speed and impulsiveness. It became treacly and smeared. It was an admittedly rough journey to get us to where we are now with our software settings, hardware configuration and our new standards for music playback in our crib. We must say hats off to Peter and his wife Cisca who spent so much time making the dream of sophisticated computer audio come true. Cisca is the one who builds the DACs down to the smallest SMD part! And their long hours are far from over. A new XXHighEnd version is ready for download with new options to fine-tune operational parameters. Alongside that, the Phasure forum remains moderated and maintained and thousands of posts proof how alive that forum is. It seems Peter really has created a project for life.


We began this article with a question. Was it really worth all our effort, frustration and endurance to get XXHighEnd and the Phasure NOS1 DAC to perform as advertised? At this point we answer with absolutely. Besides entering a new sphere of musical enjoyment, we learnt quite a bit about noise interference and its audible side which today's review subjects reveal so easily - and how to repel it. As this adventure showed, it wasn't via the usual audiophile suspects. So XXHighEnd is definitely not the easiest software player on the market nor was it ever intended to be that. Its numerous interacting parameters are not easy to grasp even for its author. Whilst his forum offers a lot of helpful feedback from other users, twirling the virtual knobs gets you on a head-spinning roller coaster of enforced learning. This is comparable to the usual audiophile tweaking with cables, amplifiers and footers but now occurs exclusively in software. The results can be very bad indeed but fortunately there's a save'n'restore option for these settings. Though not as easy as iTunes even in combination with Amarra or Audirvana, to us XXHighEnd is currently the by far best software player extant. In combination with the Phasure NOS1 DAC the sound quality sits lonely at the very top. As our new reference, it will make future reviews both easier and rather more critical.

Condition of component received:
Excellent. Software is by download, DAC arrives boxed.
Reusability of packing: DAC comes in double cardboard box which is reusable many times.
Website comments: Contains thousands of posts across hundreds of topics. Posts can be long.
Completeness of delivery: Fully. The software license is valid for all PCs in a single household.
Pricing: Competitors—anyone paying attention—should take note.
Human interactions: With humor and very responsive through sometimes lengthy e-mails.
Remark: For novice users wanting the best playback, a short guide with recommended settings for a guaranteed start would be good. Use of the Phasure NOS1 DAC should be mandatory with the XXHighEnd software.

XXHighEnd website