The first moment you see the product, you get the impression that this is just a home audio device. In front, an LED on the right indicates the sample rate. On the left, alongside the power button, is a source-switching button. And the Z1S is about enjoyment, at least that is how I feel about it after using it for the past few weeks and trying it with a variety of different amplifiers (both with headphones and speakers).

MQA (the format used by Tidal for the Masters files found in its HiFi Plus tier) is also supported, with full decoding up to 384kHz, meaning that the complete ‘three unfold’ decoding process is performed internally, as opposed to just the final unfold in the manner of an MQA ‘renderer’. The MM-/MC-Phono- preamplifier "ZEN Phono" will join the affordable ZEN product line of iFi Audio. It features four different gain stages, a balanced pentaconn connector and an "intelligent" subsonic filter.

Balanced. Blissfully quiet.

High-resolution D/A conversion is possible via iFi’s tried and true Burr-Brown DAC chip setup with a four-channel True Native design. This, in theory, lets PCM and DSD signals take separate pathways, so they stay bit-perfect before conversion. Next, I switched to the USB input and connected my Envy X360 laptop to the ZEN One Signature using the supplied USB cable. While I was dazzled by the ZEN One’s Bluetooth connection, once I played some tunes through Roon, I realized I hadn’t heard anything yet.

The One is not a further update of the ZEN DAC which continues as before, offering a brilliantly cost effective way of decoding a USB signal. The One instead sits above it, doing both more than the basic DAC (quite a bit more in fact as we shall cover) and offering higher performance while does so. It might be logical to argue that the One is a more conventional device (to a given value of ‘conventional’) than its single function stablemates and in this most reactionary of markets, that can often be an advantage. I haven’t tested the D50s myself, and my only hands-on experience with Topping DACs was with the less-expensive E30. But with that one, I could definitely hear a difference between powering the unit with USB versus plugging it into my SurgeX, whereas I couldn’t hear such a difference with the Zen One Signature. So that’s something to consider, depending on your setup.The ZEN One Signature is also the first ZEN DAC to support all hi-res: DSD256, PCM384, MQA384kHz, Bluetooth 96KHz. Other new features include; The new ZEN Stream extends iFi's ZEN series by adding a compact streaming bridge. In contrast to the other devices unveiled recently, as part of the 2nd generation, the new ZEN Stream is a completely new development. Next to the display is another multi-color LED that indicates the audio format and sampling frequency of the file in use. Again it lights up in different colors to show different values, like Yellow for PCM with a sampling frequency of 44.1 or 48kHz. This input also shows input in use when selected, with Blue/Red meaning Bluetooth and Green meaning S/PDIF or USB. This product has a 5Hz to 80kHz frequency response and 4V/2V max (BAL/UnBAL) outputs. Its output impedance is 72Ω/36Ω (BAL/UnBAL) or lower. Plus, it has a -105dB(A) @ 0dBFS SNR and less than 0.002% @ 0dBFS THD+N. One last thing to note is that the output of the Z1S, from the unbalanced RCA’s, is over 3V, which is quite a bit more than the usual approx 2V output of an unbalanced connection. This can actually cause clipping on the input of certain amplifiers, depending on the design of their preamp stage. As there is no volume control on the Z1S, you would need to drop down the source to avoid this if it is your case.

As far as formats, the Z1S accepts PCM (up to 192kHz), DSD (up to 12.3MHz), DXD (352.8/384kHz), MQA and Bluetooth 5.1 (aptX, aptX HD, aptX Adaptive, aptX LL, LDAC, LHDC/HWA, AAC and SBC). So you should be covered no matter what kind of format you are wanting to use. With inputs for Bluetooth, USB and optical/coaxial, the iFi ZEN One Signature is the only DAC (Digital to Analogue Convertor) you need. Taking the ZEN DAC Signature as its basis and adding high quality Bluetooth connectivity, the ZEN One Signature truly has all bases covered.If, like most listeners in this day and age, you get your music from a digital source such as a streaming service, via files saved on your device, or even the good old compact disc, then a DAC is going to need to sit at the top of your audio food chain. Your integrated stereo amplifier or headphone amplifier may well have a DAC already built into it. But, if you’ve built a headphone or speaker listening setup around separate analogue components then you’re going to need to partner them with a digital-specific device that’ll be able to handle all the file types, formats, and source devices that you plan on using to play your music with.