˻ PREMIERE ˼

⌈ In 2013, LUMÏN burst into the pantheon of world audio files players manufacturers. Their first player simply named Lumïn was a challenge to the competition. We are testing the latest transport of this company, the U2 model, belonging to the new generation of its products. It's its WORLD PREMIERE. ⌋

ECHNOLOGICAL PROGRESS REVEALS ITSELF IN MANY WAYS. However, if I were to generalize, it's usually about what you might call a "race": faster, further, harder, deeper. It is so that in technology, change for the better is associated with breaking new boundaries. In audio, this does not always work, because tube amplifiers will not suddenly start to play with lower distortion than the tubes themselves, and in loudspeakers, a flat frequency response and low distortion are just a means to an end, and often lead designers astray. But this seems to be an exception. All other products benefit from the principle I am talking about.

This group also includes audio file players. However, there is no other as rapidly growing sector of our industry as that related to file playback. These are, in general, products based on computer and related technologies, and that means that the changes are more rapid in them. Faster, with less distortion and noise, and with larger files - this is the direction that was given to it at the very birth of this industry and which will not stop soon. But it is thanks to this that we get products that sound better and better and are better able to play audio files. An example of such an evolution is the U2 file transport from the Hong Kong company Lumin, tested by us this time.

▌ U2

The U2 is the latest addition to its portfolio. There it joins the top U1X and the smaller U2 Mini (test → HERE). It is part of the "new wave", represented by the T3 player, tested in the January issue and featured on the cover of our magazine (more → HERE). "New" in this case means primarily a change of a processor, enabling faster signal processing, but also packaging the device in a housing known so far from the top transport of this company.

⸜ FEATURES U2 is a stereo audio files transport. This means that it performs an analogous function to CD and SACD transports. It takes audio files from external media and converts them into a digital audio signal. More processor power allows you to play all, even theoretically and not practically, available sampling frequencies: DSD to DSD512 and PCM up to 768 kHz and 32 bits. The device also natively decodes, i.e. unpacks MQA files in their entirety, and works with all major streaming services, such as Tidal and Qobuz. It can also work with Tidal Connect and Spotify Connect. It is AirPlay compatible and Roon Ready certified.

Unusually for file transports, we can also use it to adjust the volume. This is ensured by a digital algorithm called LEEDH PROCESSING. Used by Lumin since 2020, it was developed by the French specialist GILLES MILLOT from the Acoustical Beauty company, offering high-end loudspeakers with many interesting patents. It digitally regulates the amplitude of the signal without - as the company assures - changing its shape and resolution. Referring to measurements made by SUPSI (University of Applied Sciences and Arts of Southern Switzerland), he calls his solution "lossless".

For those who like to experiment with sound, Lumin has prepared two upsampling options: to DSD256 or PCM 384 kHz, for all file types. I approach such functions with caution, because usually the CPU power is too low to perform this conversion correctly. U2, however, received the latest processor and perhaps it will finally be a useful option - we will check it in the listening test.

⸜ INPUTS & OUTPUTS This is the company's first product with THREE USB ports. One of them has an architecture in which the signal is sent without any buffers - the company calls it Direct-Coupled - and we connect the digital-to-analog converter to it. Two more are used to connect pen drives, and HDD or SSD drives.

The decoded digital signal will be sent out not only via USB, but also via the classic audio outputs: RCA and BNC coaxial, optical Toslink and an AES/EBU connection based on an XLR socket. However, you have to remember that the PCM signal is limited to 24 bits and 192 kHz. DSD in its original form cannot be transferred in this way. We can do it when the D/A converter works in DoP mode, i.e. DSD over PCM. It is "packaged" on the input to look like PCM and "unpacked" on the output. This is a possibility, but you need to know that the sound is then slightly worse than with "normal" transmission.

Files for this type of product, such as U2, are delivered wirelessly, via a Wi-Fi network, or using a wired connections, i.e. a LAN network. Lumin favors the latter connection as more reliable. RJ45, i.e. Ethernet, connections are used to connect to the router (or LAN switch). The tested transport has such an input, but the manufacturers clearly say that it is secondary to another one - the optical SFP (Small Form Factor Pluggable).

THE MANUFACTURER OF U2 EPHASIZES AN IMPORTANCE of the fact that this is its first file transport outside the top series, which received a full-size, thick, aluminum housing; we saw it, for example, in the T3 player. This is important because it provides better protection against RF and EM interference, and it is more rigid, and thus its vibrations have a smaller amplitude. And in digital products it is as important as in analog products, although it affects other parameters.

⸜ POWER SUPLLY Another point in the design of the U2 that is worth paying attention to is the power supply. You see, the company started its adventure with devices with an external linear power supply. After some time, it turned out that in order to fit in the budget and simplify the operation of devices, it was necessary to reach for switched-mode power supplies. This manufacturer has developed its own solutions, which it says are used in the best industrial installations. However, a good linear power supply is better than a good switching one. There are exceptions to this rule, we need to mention Linn and Chord Electronics devices, but that's it - exceptions. So the U2 uses a classic, linear power supply with a toroidal transformer.

⸜ CONTROL If we have Roon, we will control the device through its own application. We can also use the JPLAY (more → HERE). However, this is not necessary. Lumin was one of the first specialist companies to develop its own control application. It is available for both iOS and Android devices.

This platform is constantly being improved and enriched with new functionalities. Last year they added: Free FLAC Lossless radio stations, Leedh Processing Balance Control volume control (for players with ESS DACs), improved sound for Spotify Connect and an experimental "Roon Only" mode.

It is a really well-thought-out device, offering a lot of connections. And well made too. And besides, it has an extremely refined interface in the control application, which we can replace with Roon or JPLAY. We can also use the option of optical connection to the router, which is a very important feature - in the future all audio products should be able to do this.

Transport is ready to go straight out of the box, but to hear what it can really do, we need to give it about 300 hours of "warm-up", that's important!

▌ ODSŁUCH

⸜ HOW WE LISTENED The Lumin U2 audio file transport was placed on the Finite Elemente Pagode Edition Mk II rack on its feet, and those on the Acoustic Revive RKI-5005 pads. Its USB output was connected to the AYON AUDIO CD-35 HF EDITION SACD player and - alternately - the Mytek Liberty Mk II D/A converter. Mytek Brooklyn Bridge file player was my reference point.

The player was connected to the router through my system, consisting of a dual LAN SILENT ANGEL N16 LPS switch with its two modules in series, powered by a TIGLON TPL-2000A cable and a TIGLON TPL-2000L LAN cable; more about it → HERE; the router was powered from the JCAT Optimo 3 Duo power supply.

During the test I tried the DSD upsampling option and it sounded really nice. This is one of the few file players that do not spoil the sound in this way, do not reduce its resolution. This feature also warmed up the sound. That's why we need to determine what we need. I performed the test without upsampling./p>

⸜ Recordings used for the test | a selection

⸜ BILLIE HOLIDAY Body and Soul, Verve Records/Tidal Master, MQA FLAC 24/192 (1957/2012).
⸜ MICHAEL JACKSON, Thriller. 40, Epic/Tidal Master, MQA Studio FLAC 24/44,1 (1982/2022).
⸜ YES, Close to the Edge, Atlantic Records/Tidal Master, MQA Studio FLAC 24/192 (1972/2013).
⸜ FRANCO AMBROSETTI, Nora, Enja Records/Tidal, FLAC 16/44,1 (2022).
⸜ LUCIANA ELIZONDO, Cantos De Amor Y De Ausencia, The Audiophile Society/Tidal, FLAC 16/44,1 (2022).
⸜ LUCIANA ELIZONDO, Cantos De Amor Y De Ausencia, The Audiophile Society/Master WAV 24/48 (2022).
⸜ THOMAS KESSLER, Close to Silence, Hypersensitive Records/Tidal, FLAC, 16/44,1 (2022).
⸜ THOMAS KESSLER, Close to Silence, Hypersensitive Records/Tidal, Master WAV 24/96 (2022).
⸜ ARNE DOMNERUS Jazz at the Pawnshop. 30th Anniversary, Proprius/Tidal, FLAC, 16/44,1 (1977/?).
⸜ ART PEPPER, …the way it was!, Contemporary Records/Mobile Fidelity Audio Lab UDSACD 2034, DSD – rip z SACD (1972/2008).
⸜ MARK HOLLIS, Mark Hollis, Polydor/Tidal, FLAC 16/44,1 (1988/2007).

» Recordings come from HIGH FIDELITY playlist: Lumin U2, available in Tidal → HERE .

»«

I HEARED IT ALREADY WITH BILLIE HOLIDAY’S Body and Soul, but it was the new remaster of MICHAEL JACKSON's Thriller, released on the 40th anniversary of its release, that let me hear it fully: Lumin transport loves strong, low bass (by anthropomorphizing I mean how it modifies the audio signal). This is a device that plays a strong, low-based sound, in which the range in question plays a very important role.

Red Mitchell's double bass on the Holiday album had a strong "presence", its body was quite large, which - for a monophonic recording - is especially important. But as I say, it's the low bass in Billie Jean, those strong opening hits of Beat It, that showed the Lumin quality I'm talking about. The device presents this range in a soft, very natural way, bringing the whole sound closer to the line connecting the speakers. The soundstage is nice, has good layers, but the presentation is so big, so tangible, that it seems to be placed really close.

U2 has a tendency to arrange the sound into longer phrases. Let me explain. The tested device plays legato, combining individual phrases within a given instrument. It is resolving, which is why it differentiates instruments in time and space, not to mention timbre. At the same time, already within a given instrument - and I paid special attention to this with the FRANCO AMBROSETTI flugelhorn on the Nora - it does everything to make it as smooth, soft and internally consistent as possible.

This inner vigilance for consonances, strong bass and smoothness allowed the vocals of LUCIANA ELIZONDO from the Tonada De La Luna to resound in a spectacular way. The recording prepared by the Audiophile Society, part of the Chesky Records label, has a huge momentum and we have an almost physical feeling of being in a large space. U2 was able to show its greatness, slightly bringing the vocals and instruments towards me. It did not exaggerate in imposing their presence.

It was similar with THOMAS KESSLER's piano from the Silence, played both from Master WAV 24/96 files and from Tidal (FLAC 16/44.1). It was extremely atmospheric, dense, nice sound. And I think that's the main feature of U2's sound. Bass, space, tangibility - it's all true. But they are not important themselves, but rather what they do. Just like with DSD files ripped from Jazz at the Pawnshop SACD. Although the same SACD disc played with the Ayon had greater depth and more clearly shaped bodies, it was the U2 that played this exceptional material more pleasantly, in a, how to say it, polished way.

I would compare the way Lumin shapes the sound to what is done with vinyl records played using a high-class, but warm-sounding turntable. ART PEPPER from ...the way it was!, the album from 1972, which collected his recordings from 1956-57 and 1960, in the version released by Mobile Fidelity, sounded like this: strong, dense, with an emphasis on the lower midrange. I think it's a conscious choice. I remember well the original, the first file player in the history of this company, and all subsequent ones - I think that their creators wanted something like this, especially with DSD files.

It seems that with the latest generation of devices from this Hong Kong company, it returns to its roots in a way. After a momentary infatuation with high resolution combined with the pursuit of the greatest possible selectivity, I can hear a return to density and smoothness. You see, you can't have everything, at least not in audio. Even if you have all the money in the world you have to choose between different aspects of the sound. For me, what Lumin did in U2 and before that in T3 is the right path.

After the days of precision, a very good resolution remained. That's something that makes U2 stand out. However, there is something more behind it, richness of the sounds. When we hear MARK HOLLIS from his solo album, it has a not completely open treble. This is because the microphones during these recordings were placed far away. Instruments standing in a semicircle, to which only a few additional sounds were added, are more open and have an extremely natural timbre, even though they seem not entirely "ordered".

The transport, which we are looking at this time, showed these nuances nicely, without exaggerating in the analytical nature. It's a device that plays with a strong treble, it doesn't withdraw it, but it also doesn't base sonority on it, it's not the goal. In this respect it resembles Marcin Ostapowicz's XACT S1 player (more → HERE). So if someone is looking for a strong detail, if someone likes a clear attack and transparent sound, they must combine the U2 with a digital-to-analog converter that emphasizes these aspects. Or just look elsewhere.

▌ Summary

LUMIN GOT US USED TO THE FACT that its products are very well built, easy to use and offer a very nice sound. Along with the new generations of their products, in which they used more and more efficient processors, more precise clocks and better power supplies, the clarity of recordings increased, and their dynamics also improved - the soft "underbelly" of devices used to play files.

The latest generation of these products brings something more: resolution AND richness. CDs and SACDs are still better in this respect. However, U2 plays in such an internally complex way, offering comfort incomparable to any other audio device, opening an almost infinite world of recordings to us through streaming services, that I understand people who will choose Lumin forgetting about silver discs .

U2 will give them warmth, give them depth, give them fullness. Its bass will be low and dense and rather soft than precisely defined. The device does not drag it out, but rather extinguishes it nicely. The top is rounded and creamy rather than luminous. Which does not affect the resolution of the presentation. The latter is high. The U2 is therefore a versatile product, offering very enjoyable listening sessions of all types and styles of music with an extremely natural sound. I would even say that the sound is charming, bringing peace and joy.

▌ DESIGN

U2 OWES ITS SHAPE TO the first product in the company's history, the Lumin file player, from 2013 (more → HERE). The external design and mechanical construction turned out to be so versatile that they have withstood the test of time and today, ten years later still look attractive and fresh.

» FRONT The new transport from this company is the first device of this type, apart from the top model, in which a housing with a front wall milled from a thick piece of aluminum in the shape of a circle is used. A hole was cut in it in which a display with a blue filter was inserted. It hasn't changed since the beginning either. It's small, but it holds the name of the artist, the title and the exact file data - that's important. Also the rest of the housing is made of aluminum plates.

» REAR The back is hidden under the extended top panel. This solution was taken over from Linn players, on which Lumin's creators modeled themselves. This is to protect them from damage, but it also makes plugging and unplugging the XLR and Ethernet plugs more difficult. All jacks are soldered to the PCB, but XLR, BNC and RCA are high end species.

» INSIDE These inputs are buffered with matching transformers. Interestingly, each of the outputs received its own transmitter, which makes them independent of each other and separates them. Even more interesting is that the first two are preceded by Cirrus Logic CS8406-CZZ systems, and the next two by Wolfson Microelectronics WM8805. The proper transport of files was assembled on a separate PCB plugged into the main one. There is a microprocessor, hidden under a heat sink, and memory chip. Digital filters, MQA decoder and upsampler are hosted in a separate Altera Cyclone IV DSP.

» POWER SUPLLY The voltage for the U2 is provided by a linear power supply, which is a change compared to other devices of this company from recent years. A medium-sized toroidal transformer and a rectifier with the first voltage stabilization stage are enclosed in a steel screen. A transformer with a resin-filled core was purchased from Plitron. This Canadian company changed its name to Noratel Canada Inc. in 2021, so the transformer must come from Lumin stock; This is a unit made in China. The remaining voltage filtering stages are placed on the main board, next to the powered circuits. You can see there, among others, chokes with a core. ●

▌ Technical specifications (according to the manufacturer)

Streaming protocol: UPnP AV
Supported files:
• DSD: DSF (DSD), DIFF (DSD), DoP (DSD)
• PCM: FLAC, MQA, Apple Lossless (ALAC), WAV, AIFF, MP3, AAC (M4A)
Sampling frequencies, bit depths:
• PCM, 44.1-768 kHz, 16-32 bits, stereo
• DSD, 2.8-22.6 MHz (DSD64-DSD512), 1 bit, stereo

Digital outputs:
• USB: DSD512 | PCM 44,1 - 768 kHz, 16 - 32 bits, stereo
• Toslink, RCA, BNC, AES/EBU: PCM 44.1-192 kHz, 16-24 bits ⸜ DSD (DoP, DSD over PCM) 2.8 MHz, 1 bit

Digital inputs:
• optical SFP Network 1000Base-T
• LAN Ethernet Network 1000Base-T
• USB – pendrive, USB – HDD/SDD, (single partition FAT32, exFAT lub NTFS)

Dimensions (W x D x H): 350 x 350 x 60.5 mm
Weight: 6 kg