XOno 2019 Reviews

Randy T. / USA (11-02-2023)

Randy posted his really great review in the same thread on diyaudio.com as Dieter B. (user rhthatcher). Enclosed is the link to his report:

New build: Pass XONO 2019 (RSTaudio)

It’s certainly worth noting that Randy ran a Pass Labs XP-15 for five to six years before the RStAudio XOno 2019 and has now replaced it with the XOno!

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Dieter De B. / Belgium (31-01-2023)

Dieter has published his very readable report as a thread on diyaudio.com (user dctrl). Under the following link you can read his report:

New build: Pass XONO 2019 (RSTaudio)

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Paul D. / United Kingdom (21-11-2021)

I had never been entirely convinced of the argument that components need ‘burning in’ until last night. The XOno has been switched on for a couple of weeks now. I’ve set the loading on the Audio Technica AT33PTG to 100 ohms, used the line (aux) input on my Naim 32.5 with the XOno gain set to 66dB (76dB overloads that input). I switched the Naim 160 on half an hour before listening too. I have had this amp combination for over three decades so I know its sound intimately.

Last night was a revelation. I fully intended to allow myself only an hour or so before getting other duties. I started with Magnetic Fields 2 to test the dynamic capabilities of the system and … ‘Wow!’

The percussion is incredible; start, stop, no decay, and deep! The MC phono stage on the 32.5 is no slouch despite its age. It isn’t a case of more bass from the XOno, it’s lower bass and tightly controlled. The Naim also has a relatively forward presentation which can increase the perception of greater dynamics. I had originally thought the XOno a little understated by comparison. This is not so, as demonstrated by the next album, The Phantom of the Opera. This opens with spoken voices, followed by a full orchestral overture, then jumps back to a single female voice. It never missed a beat throughout, the voices are crystal clear, well placed in the soundstage and have a real sense of body. The overture can easily overwhelm lesser systems with its volume and complexity, not so here. I ended up listening to the whole side; it has phases of almost whisper quiet voices followed by orchestral sections with passionate and powerful male and female singing. All delivered with conviction and emotion.

Well … four hours later … and a two inch stack of played albums on the table next to my chair … I am completely converted. This is an extraordinary piece of equipment. I played a full range of music that evening; Miles Davis, Joe Cocker, Pink Floyd, Focus, Sade, Michael Jackson, Led Zeppelin, Rag ‘n’ Bone Man, Rush and several others. The surprising thing that I noticed was that, despite its dynamic sound, it doesn’t impress its own character on any of the music played. It just seems to let the music flow through.

Time to put my F5 turbo project back on the workbench and get it finished! An Aleph P 1.7 shouldn’t be too far behind either.

Thank you, thank you, thank you for making this project available.

Best wishes, Paul

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Jochen B. / Germany (08-04-2021)

An unexpected reward!

My first attempt at playing after the not-so-simple assembly succeeded right away. I fed the Xono with the signals from my somewhat reserved Rega cartridge, and lo and behold, it was obviously love at first note! What previously sounded restrained and even a bit musty with my other phono preamps (one tube, one transistor) now seemed downright freed. The XOno presents a lot of detail in the mid and treble range without sounding annoying or letting the music fall apart. Transients come out of the speakers quite quickly and sometimes really powerfully. Compared to my old Whest preamp, on which I had mainly used the cartridge, all recordings sound much fresher and livelier. Stylistically, I only listened to jazz and classical music.

But the best thing is the incredibly wide stage that the XOno puts on. I have never experienced anything like it before. Even my tube amp (an EAR 834P replica), which already delivers a remarkable width and depth, can’t keep up.

What I missed a little in the first days was a more powerful upper bass. Electric basses kind of twang instead of signalling that they can also do something else. Maybe I was a little spoiled by the tube pre. I don’t want to ignore the fact that the tube overdoes it a bit with its pressure from the entire bass range. But that was just a first impression, and in case of emergency (e.g. when playing my old Herbie Hancock records from the 80s) I still had an external subwoofer up my sleeve.

The first time I listened to classical music, I found it more stress-free than with the other two preamplifiers. To test the equalizer functions, I had put on some old Decca records with Khatchaturian pieces; they actually came across more lively and precise with the Decca EQ setting than with the simple RIAA setting. Also, the resolution of the individual instrument groups and especially the spatial placement of individual instruments was (and still is!) better than with the RIAA characteristic. Overall, I am now much more in the middle of the action than with the old Whest; in this respect, the XOno behaves more like a tube, but allows for even more openness and width.

After the first listening impression, it was already clear that a few chairs would have to be moved. In the meantime, the Whest has been replaced and the Xono takes its place without competition. I had not expected that at all! But then, a few weeks later …

Was it my imagination or had the sound of the XOno gained even more stability and fullness? It must be so, because I hardly recognise my rather delicate MC system now – it simply plays more confidently than before. Besides, the XOno still comes up with pleasant surprises. For example, I recently followed up on a hint in a forum that LPs cut in the 1980s and 1990s using Teldec’s Direct Metal Mastering (DMM) process were comparable to the characteristic curve of the older Teldec records. So I immediately searched my collection for DMM discs (mostly recordings on Enja or French Blue Note reissues). Among them were several that I had not paid much attention to in terms of sound. You could hear that they were well recorded, but I would not have called them outstanding or even audiophile. With the “Teldec” equaliser setting of the XOno, this impression changed dramatically.

I didn’t want to believe it at first. Compared to the normal RIAA setting, the spatial separation to the side and to the rear is clearly improved on most records recorded and mastered in Germany. Basses are more powerful and the high frequencies are unbelievably concise without being annoying on my very neutral and sometimes mercilessly honest amplifier. Soon I will have to search the record rack again and listen more closely! For me, however, the conclusion is already after the first play: DMM records are better than their rather mediocre reputation, they just need to be equalised properly. I’m so glad that I ordered the EQ boards!

I made the sound evaluation with this equipment configuration:

  • Rega RP8 turntable with Apheta 2 MC cartridge
  • Whest PS.30R phono preamplifier
  • DIY replica of an EAR 834P phono preamp (heavily modified)
  • NAT Symmetrical preamplifier
  • Accuphase P-800 power amplifier
  • JBL 250ti loudspeakers (modified)
  • DIY cables Neotech NEI-3001 MkIII (symmetrical)

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Steven W. / USA (09-02-2021)

Ralph Stens:
The complete review can be downloaded as a pdf file: Pass XONO Clone, Boards by RStAudio

The purpose of this is to help you decide if you want to build the RStAudio XONO phono preamp. For me it was worth the cost and effort. Without even a break-in the improvement was significant, not something I had to go back and forth to figure out if and where it was better. It has more presence, distinct bass, delicate highs, more impact, and more spacious music. How do you decide if you want to build this? All I can do it to list my equipment and you can see where your equipment may fit in, including equipment I changed out as I think each set of equipment was better. I’m not suggesting anything I own or have owned is good or bad. Deciding to build this is a bit of a leap of faith. After about 3 weeks the XONO is setting itself apart from my other phono preamps. Instruments are separated with space. The sound is natural and so pleasing. Albums sound completely different on this phono preamp. I am amazed at the sound it produces and I am completely satisfied.

The XONO Sound:

My audio equipment for this audition:

  • Rega RP8 with AudioMods Series Six tonearm with VTA and Sumiko Blackbird MC cartridge
  • DIY Audio Mezmerize B1 Buffer balanced build, a DIY inverter, two power transformers
  • DIY Pass Aleph 5 mono amps with 650VA transformers
  • DIY interconnects using Cardas solid silver wire in Teflon tubing
  • 1974 Klipschorns (modified)
  • Nordost Frey speaker cable
  • Transrotor turntable with a Sound Smith Sussurro cartridge and Kuzma 4-pont arm.

Was it worth the effort and cost? Yes! Improvements were immediate and obvious without break-in and warm-up. The next day I let it warm up for several hours and had a listen. From highs to mids to bass, everything is better balanced, more spacious and detailed. Cymbals sound like metal and are clear and distinct even when faint. Bass extends lower with more detail and authority. Background sounds such as reverberation are separated more from the primary instruments and vocals. Surprising to me was that record noise was less apparent.

Three weeks later the sound with the Transrotor setup through the XONO is breathtaking! It sounds so natural. Before the Transrotor/RTP5 vs. Rega/Boozhound were not that much different – yes, the Transrotor setup was better but insufficiently so. Now the difference is simply wonderful! Words cannot describe it. An album played on the Transrotor/XONO really stands out and is so pleasing. The same album just doesn’t sound like the same album on the other setup, thanks to the XONO!

I feel I now have a piece of that top end sound I have read about. My vinyl is back on top ams while I enjoy the sound I get with my digital setup I feel it is just contender. I can relax and enjoy music and not wonder what to do next.

I want to thank Ralph Stens for making this experience possible!

Steve W., USA

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Thomas C. / Germany (19-11-2020)

Perhaps the blackest of the black ones: XOno2019

I’ve been following the progress on the RStAudio site for a long time. When the day came, I was sure that this could be something for me. Changing the parameters with an rotary encoder or even a remote control is something special. I always need a little rest for these settings and now I don’t need any tools at all.

The package is delivered with a detailed documentation. The quality of the boards was not spared. I was a little bit exhausted by the variety of parts when the packages from Reichelt and Co. arrived at my home. I printed out the assembly plan in DIN A3 to get a better overview.

Whenever family and job allowed it, I soldered diligently and after a few weeks the parts that still had to be installed became more manageable. Mr. Stens always answered questions about the construction quickly and comprehensively. After the first commissioning the housings came from Italy in the black version.

The first soundcheck was done with the case not yet closed. I was relatively quickly thrilled. What immediately impressed me was the deep silence. One of the previous writers describes this absolutely right as deep black. I would like to mention that this is not usual. W-Lan and cell phone were noticeable with the predecessor. Even the use of an HDMI cable from the TV to the AV receiver does not produce any hum. I was particularly pleased that my real motive to buy a new phono stage was fulfilled. The crack every 60 seconds is gone.

My sound evaluation is accordingly positive. Crisp bass, a beautiful stage almost three-dimensional. The trebles are as pronounced as I would like them to be. No details are omitted. The preamp fits perfectly into my system.

I built up the version with servo controllers and the controller with a large display. The display is unfortunately only available in black and yellow. Not quite the right thing for a Rhinelander. But also for it was provided. If the display is too bright in the long run, it can be switched off in normal operation.
(Ralph Stens: This is a joke about the two colours (black and yellow) of a football team here in Germany. The author is not a fan of this team.)

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Philipp N. / Germany (02-11-2020)

During the last weeks I have used every free minute to listen to music through my phono system and the RStAudio Xono. So I have also postponed my report, because I just could not tear myself away.

I am not a tester and my experience is limited, especially with regard to the different devices in my system. But I can definitely say that this Xono has taken my listening experience to a new level. Big orchestras are really big now! The individual sections are clearly distinguishable and wonderfully precise to locate in the room. Recordings with smaller ensembles create an intimacy that I have never experienced before with any system.

In my opinion, these experiences can be traced back to the fact that the Xono can really do everything. Dynamics and detail, warmth and speed. It delivers everything as a matter of course when the music demands it, but never plays itself into the foreground by influencing the sound. I don’t want to use the much-read phrase “I’m rediscovering my record collection”, but I would like to say that with this phono stage I can’t get enough of listening to music and I finally feel like I’m not thinking about my system anymore.

I don’t want to leave unmentioned how, in the version I have built up with the servos and the controllers, the whole thing can be adjusted wonderfully comfortably and precisely. Thanks to the detailed and extensive documentation, the setup was no problem at all and was in itself a great project.

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Meinolf S. / Germany (04-10-2020)

It is not difficult to say that this version of a XONO dwarfs pretty much everything I have heard so far.

Essential: the XONO2019 plays cleanly, with a pure sound, musically, spatially and coming from nowhere.

As a listener of classical music, I immediately became familiar with the switching of the characteristic curves and took one old record – especially DGG – after another from the shelf.

This is the main feature for me: it doesn’t play itself into the foreground, but brings out potential from the pickup and turntable that I had not suspected.

I have never heard the tonal blackness from which the music comes like this before. It is completely free of noise and hum. The music, no matter what genre, detaches itself completely light-footedly from the sound transducer.

Listening to music has taken on a new dimension, and as a reaction I have first ordered a batch of new records.

Ralph Stens:
A detailed review and a very readable report on the build-up of the XOno 2019 can be found on the homepage of Meinolf S.

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Heiner F. / Germany (03-10-2020)

Recently, I have acquired the new Xono 2019 with servo controllers in the fully equipped version. I would like to try to describe the sound here. First of all I would like to say that I am really very satisfied with the old Xono.

Well, and now the new one.

I was prepared for it to sound better. Theoretically it should have less noise by using more transistors in the input and by omitting the coupling capacitors, there should be more neutrality at this point as well. Surely the other improvements also have an influence on the sound, but I can’t assign that to the sound.

Well, I have the feeling that the new one is even less noisy. That’s just a feeling, because it didn’t make any noise before. I sit about 4.5m away from my speakers and even at high levels I can’t hear any difference between the noise of the CD input and the noise of the phono stage. I find that impressive every time.

Now for the sound. I am already spoiled by the old Xono and it sounds even more beautiful now. It’s hard to describe, but I’ll try anyway. Instruments sound more natural. A bit tighter, yet with a lot of body. Complex passages are drawn through even more precisely. Voices have more details. The three-dimensionality seems even more believable. Records fascinates me even more.

These details combine to create a pleasure like I have never experienced before.

The remote control allowed me to find the termination resistor for my pickup very, very easily. And no uncertainty remained.

I have some old records and to listen to them with the right equalization instead of RIAA is impressive.

I like listening to classical music, jazz and now and then rock from my youth. (Deep Purple, Tull etc.)

Briefly to my music system:

  • Do-it-yourself record player (modified direct drive)
  • Selfmade tangential tone arm (air bearing) Thanks Detlef
  • Cartridge system: modified Denon DL103R
  • Phono preamplifier: New Xono 2019
  • Preamplifier: RStAudio VV6
  • Digitisation: Lynx Aurora 8, Acourate Convolver
  • Loudspeaker: Neumann KH420 from 80 Hz upwards, below tapped horns (Spud) do-it-yourself
  • Various room acoustic measures (self-construction)

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