Lumin U2 Mini review

Formed in 2012, Lumin has been in the high-end streamer market longer than most, and that experience shines through in the new U2 Mini network transport. It’s a slick and stable performer that could be perfect for those with a digital-to-analogue converter (DAC) in their system but have yet to get into streaming.

Before we go any further, let us clarify what a network transport is. Sometimes called a network bridge or even a network player, it is the component that accesses music from a NAS (Network Attached Storage) across a home network and plays files from streaming services or USB storage. In a nutshell, the transport fetches the digital music file from wherever it is and passes it to an external DAC (which then converts the digital data to an analogue signal that your amplifier can use).

Of course, it is far more common to find music streamers on the market that combine the streaming platform with a built-in DAC, but if your system already contains a digital-to-analogue converter – built into your amplifier or CD player – it probably isn’t worth doubling up on the circuitry. This is where a product like the Lumin U2 Mini fits in.

Features

The U2 Mini is a UPnP streamer and works with all the main streaming services – Spotify Connect, Tidal Connect, Qobuz, TuneIn Radio – and is certified as Roon Ready. File compatibility is excellent with the Lumin handling up to hi-res 32-bit/768kHz PCM files and DSD512. It will decode MQA streams too, though that feels less important now that Tidal has moved away from the format.

Lumin is proud of its new processing system and the quad-clock arrangement which ensures greater internal timing accuracy. Jitter in all its forms is the enemy of good digital sound quality, after all.

The U2 Mini is a generally well-equipped unit, but there are some obvious gaps in its specification. While Apple AirPlay is on the menu, Chromecast isn’t and neither is Bluetooth. While Bluetooth wouldn’t be our first choice for optimal performance, it remains a quick and convenient way of getting music from your phone or computer into your hi-fi.

On a practical note, we are a little surprised that Lumin hasn’t included wi-fi capability here: the U2 Mini has to be hard-wired to your network. Doing things this way has clear advantages in stability of operation and potentially sound quality, but sometimes using a wired connection is impractical or just not possible for some.

It comes as no surprise that a network transport has limited physical connections. The pair of USB Type A ports on the back can be used to connect to storage devices, but only one can be used for that at any given time. The same limitation applies if either is used as a digital output too. Beyond that, there are no other hardwired inputs apart from the ethernet socket, of course. There is a range of digital outputs though. Alongside the aforementioned two USBs, you will find an optical, two coaxials (RCA and BNC) and an AES/EBU.

General build quality is good, though the U2 Mini confirms its status as an entry-level Lumin product by missing out on the beautifully machined, rather luxurious casework found on its siblings further up the price ladder. It shares their simple, some would say basic, display though, and generally uncluttered appearance.

Lumin’s app is a mature and comprehensive piece of software that proves stable and reliable. There is plenty of adjustability on offer to hone the player to what you want it to be. It is possible to bypass specific outputs, adjust the volume level or even fine-tune the way MQA is decoded. At first, all the adjustability feels overly complex, but proves useful over our time with the product.

Despite all the positives, it is also fair to say that its layout can look a little too busy and cluttered. We think Lumin should have another look at this to improve clarity.

Compatibility

Regular readers will know that we rate the digital to analogue converters from Chord Electronics highly, so it should come as no surprise that we partner the U2 Mini with both the Award-winning Chord Qutest (£1195 / $1625 / AU$2400) and Hugo TT2 (£3995 / $5100 / AU$8500), as well as using the digital-to-analogue section of our reference Naim ND555/555 PS DR music streamer.

The rest of the system is our usual Burmester 088/911 Mk III amplifier and ATC SCM 50 speakers. We also have a PMC Cor amplifier and Epos ES14N combination on hand to hear how the Lumin copes in a more price-compatible context, and the Audiolab 9000N (£2499 / $3499 / AU$5500) music streamer for comparison.

The Lumin proves easy to integrate into our system and we manage to access our music library (a Naim Uniti Core) and log into our various music streaming service accounts without issue. Given that a network transport’s job is to access digital music files from various sources and then simply send them to a partnering DAC, it would be easy to assume that all such products would sound the same as long as none of the ‘0’s or ‘1’s are lost.

It is fair to say that in any competently designed streamer, there would be enough in the way of error correction and other processing to ensure that any such losses are absolutely minimal. Yet, in our experience, there are notable differences in sound quality between streaming transports, and this is borne out again when we compare the U2 Mini’s performance to that of Audiolab’s 9000N streamer, with both feeding an outboard DAC.

The Audiolab wasn’t chosen by chance for the comparison. This five-star streamer also uses the Lumin streaming platform and as such is the perfect benchmark at this level. If anything was going to sound the same as the U2 Mini, then the 9000N through its digital output would be it. But it didn’t. Now, the Audiolab 9000N is a terrific product and the current holder of our Product of the Year Award in the music streamers category, but it didn’t take long to decide that the Lumin delivered better results with a good external digital-to-analogue converter.

Sound

When we play Dvořák's New World Symphony (a 16-bit/44.1kHz recording) we are initially drawn to the Audiolab’s rendition. It sounds more forward, crisper and seems to have a touch more punch. As we listen longer, the Lumin’s more neutral and measured approach to music replay gains in appeal. It has a calmer manner and feels more composed. We notice that the U2 Mini digs up a touch more low-level information and that means we are more aware of details like the scale of the recording venue and placement of the orchestra. Through the U2 Mini, the quiet between the notes is more emphatic and that allows the harmonic decay of instruments to come through with greater clarity. We also notice that the Lumin renders the stereo soundstage with a little more depth, though there isn’t much to differentiate the products when it comes to image focus or width. The differences in each particular area aren’t massive, but put them together and our clear preference is for the ’Mini.

Switch to a DSD recording of Stevie Wonder’s Innervisions and the Lumin continues to impress. Its rendition is detailed and energetic, capturing the drama of Higher Ground with its hard-driving rhythm track superbly. We get a fine sense of composure and the ability to organise the dense musical backdrop in a clear and musically convincing way. Wonder’s distinctive tones come through with passion, texture and nuance intact. The music’s dynamics are delivered with fluidity and the Lumin isn’t afraid to hit hard on demand.

Verdict

Over our time with the Lumin U2 Mini, we try out all sorts of music (and file types) from exploring our Tidal playlists to high-res recordings from the likes of the Rolling Stones, The Unthanks and Kate Bush, and this network transport never disappoints. It is a capable performer that works in a stable and reliable way. Partner the U2 Mini with a top-quality outboard DAC and it becomes a great way to bring streaming capability to your system.

First reviewed: March 2025

SCORES

• Sound 5
• Build 4
• Features 3

MORE:

Read our review of the Audiolab 9000N

Also consider the Naim ND5 XS

Check out the best DACs to pair with

Best music streamers: top network audio players tested by our experts