Hardware Reviews

Muon Digital XLR lets the music flow

Network Acoustics muon Digital XLR

Network Acoustics muon Digital XLR digital cable

The idea of a muon Digital XLR digital cable seems like an anathema, Network Acoustics are streaming specialists who have concentrated their efforts on ethernet and USB connections until now. What were they thinking when creating what is effectively an AES/EBU digital cable?

It seems that when the men behind Network Acoustics, Richard Trussel and Rob Osbourn, were working on improving their muon USB cable they decided to try the latest conductors in a balanced cable and liked the results. These guys have trouble leaving their creations alone, they’re always thinking about how they can be improved which explains the rapid evolution of their network filters which have gone from a base model ENO through the muon to the muon Pro in just a couple of years. More established brands usually keep upgrades for a mk2 or SE version to launch after a couple of years, Rich and Rob can’t wait to share their discoveries. It’s great to find genuine enthusiasts making decent products like this and to be fair they are sitting on something very big at the moment, something I can’t wait to have in the system for more than the hour or so I spent with its prototype earlier in the year.

The muon Digital XLR is a balanced alternative to the muon USB that uses the same conductors and noise rejecting tech, it incorporates in-line filtering with the same purpose which is essentially stopping noise getting into a DAC. Noise is the enemy of good sound quality, it’s what stops pretty well all formats from delivering their full potential but was not supposed to be an issue with digital systems. Yet it became clear in the earliest days of CD that digital was not delivering on its promise of ‘perfect sound forever’, initially this was blamed on timing errors caused by jitter and later by those who felt that the bit and sample rate of that format were inadequate. It wasn’t until the streaming era kicked off and eliminated many of the issues around reading a spinning disc that it slowly became evident that noise in all its various forms limits the quality of results.

Clean ground

It’s largely because we have wide band, high resolution streaming on tap and electronically quieter amplification that the effects of high frequency noise have become more obvious. This noise is in the ether as RFI and on the power line as EMI, and both varieties make a negative impact on sound quality. Network Acoustics have narrowed their focus down to the ground line as being a major source of interference. In the past most in digital streaming have concentrated on keeping the signal itself clean but the ground provides a reference without which the signal would not be transmitted, so if that reference is tainted this will affect the quality of signal. This is why Network Acoustics have worked so hard on the design and filtering of the muon cables and why their muon Digital XLR is a musically compelling connection for anyone who streams their music, be it from a CD transport or a streamer.

network acoustics Muon Digital XLR

I asked Rob Osbourn why muon Digital XLR is not called an AES/EBU cable as that’s what balanced digital cables are traditionally named but apparently “it’s not specifically built to AES/EBU standards. We designed it to sound as good as possible based on a balanced SPDIF architecture.” They have tested lengths up to 5m without drop off so it’s safe to assume it’s up to the job of carrying a digital signal from a transport or a streamer to a DAC without compromise.

As with all Network Acoustics cables the minimum length available is 1.5m (5 ft), simply because they have found that shorter lengths don’t sound as good. It’s terminated in ‘solid silver’ XLR connectors, which relates to the pins and the sockets rather than the housings which appear to be plated, but of course in an XLR the signal only travels through the pins. The cable itself is contained within a large braided sheath through which you can see a smaller but similarly flat-ish covering for the conductors. The conductors themselves are merely described as ‘high purity’ but whether this is copper, silver or anything else is not disclosed.

Muon USB to muon Digital XLR

I use a USB connection between streamers and DACs because it’s generally more transparent than the alternatives like coaxial and every dedicated audio server tends to have a USB output. I have been using the Network Acoustics muon USB for some time now so it seemed natural to contrast it with muon Digital XLR. And it’s quite a distinct contrast despite the fact that both use the same conductors, with muon Digital XLR being less focussed, it’s more of a soft focus in fact that reduces clarity of detail to an extent but delivers a more generous, relaxed and fluent sound in its place.

It’s a bit like a digital to analogue comparison in some ways, if you love a tight, precise presentation then muon Digital XLR is not going to be your bag, if however you are looking for musical ease that’s more about immersing yourself in the sound and forgetting about the mechanics of its reproduction then this is the digital connection for the job. Once it’s been in the system for a couple of tracks its relative lack of definition is no longer a consideration because the music is so engaging and easy to enjoy.

network acoustics Muon Digital XLR

Don’t get me wrong there is oodles of detail to be enjoyed, more than enough to let you know what instrument is being played and exactly how it’s being struck, plucked or cajoled into making sound. In many ways muon Digital XLR makes digital streaming more accessible and melodic. Timing is excellent for instance, the full tilt boogie of Frank Zappa’s Apostrophe has all the grunge and drive that you could wish for, and you aren’t left thinking about the quality of the recording (which isn’t exactly spectacular), instead you are blown away by the genius of the composition, arrangement and performance of a band that was a lot snappier than many imagine. You can hear the heavy compression used to cram so much into two tracks but this doesn’t detract from the enjoyment one bit.

Muon Digital XLR images well too, allowing tracks like The God in Hackey’s Bardo! to throw acoustic shapes around the speakers that seem to be carved into the air. Tonally the highs seem smoother than those delivered by USB, this might be because they are less etched or simply that there is a smoothness to the overall presentation. Bass isn’t lacking however, the leading edges may be a shade softer but the lows are deep and powerful when playing the heavy rhythms of vintage dub or anything else with low end action on it.

Muon Digital XLR verdict

This digital cable is a salve for that incurable disease audiophilia nervosa, the state of never being entirely happy with the sound of a system for very long. It takes the focus away from the filigree and concentrates on the bigger musical picture, detail is not in short supply but fluidity of performance is at the forefront. I haven’t reviewed any other AES/EBU cables in recent times but given Network Acoustics’ track record my suspicion is that muon Digital XLR is among the very finest available.


Type: AES/EBU compatible balanced digital cable
Conductor: not specified
Insulation: not specified
Shielding: not specified
Connector: XLR with solid silver pins
Length: 1.50m (up to 3m in 50cm steps)
Section: 5 x 32mm
Warranty: 2 years

Price when tested:
Manufacturer Details:

Network Acoustics
T +44 (0)2380 615 627


balanced digital interconnect cable


Jason Kennedy

Notify of
Inline Feedbacks
View all comments