Noise. That’s what’s wrong with digital audio reproduction. Yet how could this be? CD introduced the silent background, the hiss free ‘inky blackness’ that allowed the music to stand out. But it didn’t... it just seemed to; digital audio appears to have very low noise, yet when you hear a system with far, far less noise it’s a revelation. I know this for sure because I have heard it and it is not a subtle thing. This digital audio server makes it blindingly clear that noise is the biggest problem in digital audio. We know that the source is king – and in analogue this idea is well established – yet with digital audio we have been upsampling, filtering, and trying numerous other ideas to make things better and progress has been at best incremental. That’s because these technologies do not address the fundamental problem, which is that noise (even at very low levels) undermines the potential of the medium. By dropping the noise so dramatically, the ZENith SE Mk II has made more progress in the quest for high fidelity in digital audio than all upsampling and high-resolution formats combined. But first the product.
Usually the SE suffix means a few tweaks here and there that refine a product without making any significant changes to its construction. Innuos has decided to go down the decidedly British route of understatement for its SE and given that this ZENith SE MK II looks pretty much the same as its standard form stable-mate, you’d be forgiven for thinking that not much has changed except the colour of the faceplate. But you’d be wrong; this Special Edition is very special indeed.
However, what it is might need to be explained. The ZENith SE Mk II is a network server: essentially a NAS drive, but one that’s been developed specifically for the purpose of serving up audio files to a streamer or DAC. It has connections for USB and Ethernet and its operating system is related to the one behind the Squeezebox network streamers that started this whole malarkey off. There are a few competitors in the audio server market place, but nowhere near as many as there are network streamers; it’s a product type whose worth has yet to gain full recognition, a state of affairs that this Innuos will change.
A regular ZENith MkII can be purchased with 2TB of SSD drive capacity for £2,899 (or £2,299 with 1TB); the SE version is one whole pound under five grand for 2TB so where’s the extra cost coming from? There are a number of differences, but the one that Innuos emphasises is the power supply, which was designed by Sean Jacobs who runs the misleadingly titled Custom HiFi Cables, a company that appears to specialise in power supply upgrades. Sean has a background in robotics and defence electronics, but clearly has a very good grasp of what matters in audio if the SE is anything to go by.
Other differences to the regular ZENith include three anti-vibration feet arranged underneath key components within the box. It looks a bit odd when you turn it over, but if this helps then the occasional tip when you lean on the wrong corner is a small price to pay. Innuos have also upgraded the internal wiring and improved the protection against EMI (electromagnetic interference).
Most of the set up options for Innuos servers are accessed via your web browser: just go to and it will find the server on your network and give you a dashboard where you can choose to import files from various sources, select ripping format – that slot on the front is for this purpose – and even choose between fast and noisy or slow and quiet ripping modes. This is also where you can configure streaming accounts with a choice of Tidal, Qobuz, and Spotify Connect, a feature I’ve not seen on other servers to date, but whose function is limited to USB connections where you are pushing data direct to a DAC. Another feature that is even rarer is full Roon Core compatibility; few audio components have the computing power to run Roon in full effect and as a result often require an external PC for the purpose, but the ZENith SE Mk II does not. Other choices include whether to transcode DSD onboard or send a native signal to the DAC, and the option to use low latency with USB.
When using the ZENith’s USB output you can control it with an app called iPeng that was developed for Squeezebox devices. It’s a nice app, too; not free but inexpensive and better than many on the market. The Tidal/Qobuz interfaces aren’t the slickest but they sound good coming from the ZENith SE, more open than I’m used to with network streamers.
The connections on the back consist of Ethernet for network and DAC and USB for back-up and DAC. Through the network connection, the ZENith acts as a switch, meaning one less (electrically) noisy computer peripheral in the room polluting the mains with its switched mode supply.