Posted on 26th September, 2018


iFi Audio announced their xDSD portable headphone DAC/amp earlier in the year. I have had my review sample for longer than I should already, and so thought I'd better share my opinions about it.

iFi Audio


Portable amp / DAC


The Southport-based audio tech company has carved out a name for itself thanks to an award-winning array of mostly portable or desktop components. Amongst their line-up, you'll find affordable and powerful DACs and headphone amps, noise-reducing USB and digital accessories as well as pro-level equipment.

I was impressed by their Nano iDSD Black Label and so had been keeping an eye on the development of the xDSD.

iFi xDSD

iFi audio xDSD review

The portable powerhouse boasts a Burr-Brown multibit DSD1793 DAC Chipset. That chip is mated to the femto precision GMT Clock and intelligent memory buffer system derived from AMR Audio’s US$5,500 flagship DAC to eliminate jitter.

The upshot of all that is that the xDSD can play nicely with PCM up to 32/384 kHz and DSD up to 256 times the sample rate of a CD.

Additionally, the iFi xDSD offers a range of connectivity options. Firstly, wireless options employ the unit's aptX/AAC Bluetooth radio. However, if wired connections are more your thing, then the USB and S/PDIF ports are your friends.

The unit also sports a USB A port that works with Android OTG as well as iOS when used with a Lightning connection camera kit.

iFi has generously bundled a variety of adapters, as well as a USB-C cable for me to use.

iFi xDSD review

Even though I had seen the dimensions as well as promo photos I still wasn't quite prepared for how petite the hip flask-esque xDSD is. Measuring just 95 x 66.5 x19 mm (LxWxH) and weighing only 127g the DAC/amp is the epitome of portable.

The xDSD is also eye-catching. Its undulating chromed magnesium alloy casing looks fantastic - until you pick it up. It is at this point that any lurking traits of OCD will rear their head. I for one am continually wiping my fingerprints off the shiny gunmetal surface.

iFi xDSD rear ports

The rear of the unit is plastic. Before there are any grumbles from the room, this is to improve Bluetooth reception. Also, around the back of the device is where you'll find most of the ports and switches.  

The xDSD has a USB-A plug as one of the inputs, allowing it to be easily used by Apple fans and their iPhones by way of a Camera Connection Kit. The lovely folks at iFi also bundled in one of their USB-C converter cables as they knew I'm generally rocking a new smartphone of some description.

For charging, there is a separate micro USB port which means it won't draw power from your smart device. However, you can use the xDSD to refuel your phone should you need to.

Other inputs include a 3.5mm socket for both S/PDIF and optical - iFi even adds a Toslink to mini-optical adaptor in the box. Lastly, and most importantly, the xDSD has aptX and AAC Bluetooth audio built-in.

For the output, iFi employs their carefully crafted S Balanced circuit, the output of which is through a 3.5mm TRRS socket. While under normal circumstances connecting a non-balanced connector would result in damage, not so with the xDSD. Additionally, the Cyberdrive headphone amplifier stage places all parameters of the fully analogue system under digital control for a ‘best of both worlds’ scenario.

The Cyberdrive design incorporates the iFi exclusive OV4627 ultra-low noise FET input Op-Amp, and W990VST digitally controlled stepped attenuator to deliver “a new level of sound quality.”

In use

The iFi xDSD has joined me on countless commutes, as well as a couple of European jaunts. It is so easily pocketable and, once you get the hang of the controls, it's relatively easy to use. However, those controls aren't wholly intuitive.

To power on the xDSD press the centre of the volume control dial for a few seconds. As soon as the lights come on, it will be in the mode you last had it in - either wired or wireless (Bluetooth). Holding the power button in for longer still will switch between those modes - in theory. One day I accidentally switched over to Bluetooth mode, and while my love for Girls Aloud was being outed, I frantically attempted to get it back to wired without any joy. Eventually, all was as it should be, but it didn't appear that straightforward at the time.

iFi xDSD red dial

Similarly, holding in the settings button during powering on will switch the line-out mode on or off. Line-out mode fixes the output to a standard 2V and sets the volume LED in the centre of the dial to white.  When using the xDSD for regular headphone listening, the hub glows with different colours at different volume levels. The colours range through blue-magenta-cyan-green-yellow-red as volume increases. There is also a colour-coded LED indicator for sample rates.

Additionally, there are status LEDs for 3D+, XBass, and charging. However, in such a compact device this could be confusing for some users. That said, I do wonder how many users will be bothered about the sample rate indicators, especially as the xDSD will most likely be in the velvet carry pouch.

The 3D mode and X-Bass mode provides a gentle widening of the soundstage and a mild bass boost, respectively.


On the commute using the xDSD wirelessly connected to my Honor 10, I suffered no drop-outs. Yes, sometimes getting the devices paired would require some patience, but it could be that I confused it by trying it with a range of phones and tablets. Most 'normal' users wouldn't be messing around with it so much.

I am assuming that the iFi xDSD is using a standard Bluetooth 4.0 capable chip that sees it able to deliver up to 16 Bit 44.1K into an aptX stream via the in-built xDSD Burr-Brown DAC and not via the chips' own built-in decoding. However, knowing that LDAC and aptX HD are appearing more and more, it will be interesting to see where iFi goes next.

Sound quality

I could definitely hear an increase in dynamism between the xDSD and Nano iDSD BL. I still enjoy the little Black Label device, but the xDSD's amp stage certainly sounds better to my ears. Also, the new DAC on the block is more forward and engaging without being aggressive. That said, I do find the Nano iDSD BL more laid-back approach more apt to singer/songwriter or smokey Jazz tracks, so it is down to listening preferences.

Vocals are given more of centre stage with the xDSD too.

Testing the device out with the Noble Savanna IEMs I could detect a slight hiss in between tracks, but nothing outrageous. Using my Oppo PM-3 daily drivers, the audio was very enjoyable. The xDSD has been the DAC/amp I've grabbed when heading out. It has become such a regular in my kit that I forgot that I should be reviewing it.


StereoNET Applause Award 2018The iFi xDSD is a compact and highly portable DAC/amp solution that sounds as great as it looks (when polished). Its closest competitor, for me, just manages to edge it on pure sound quality but requires an additional module for it to go wireless.

The controls and indicators do take a moment to become familiar, but the xDSD easily found its way into my day-to-day life.

The iFi xDSD is flexible, performs excellently and has the look and feel of a premium product. If you are on the hunt for a portable headphone amp/DAC and wireless is a must-have feature; the xDSD is, well, a must have.

The iFi Audio xDSD is available now for £399.

For more information, head on over to iFi Audio.


      Jay Garrett's avatar

      Jay Garrett

      StereoNET UK’s Editor, bass player, and resident rock star! Jay’s passion for gadgets and Hi-Fi is second only to being a touring musician.

      Posted in:Hi-Fi Headphones DACs Applause Awards 2018 Headphones Headphone Amps
      Tags: ifi audio 


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