Easy Peasy.

PROS: Intuitive to use, significant improvement in sound quality over the internal sound of a MacBook Pro, excellent build quality, great value.

CONS: Some sync issues, slight noise with sensitive IEMs from the 2.5mm balanced out.


I would like to thank FiiO for providing me with the K3 USB DAC/Amp in exchange for my honest opinion. No incentive was given for a favourable review.

FiiO K3 (at a glance)

  • USB-C DAC and headphone amplifier
  • Decoding up to 384kHz/32bit PCM and native DSD256
  • DAC: AKM AK4452
  • Op amp: 2 x OPA926
  • Low-pass filter: TI OPA1612
  • USB chip: XMOS XUF208
  • USB Audio Class 1.0 and 2.0
  • 3.5mm SE and 2.5mm balanced headphone out
  • 3.5mm line out
  • Coaxial out
  • Optical out
  • ADC volume control
  • Gain and bass switches
  • Output 3.5mm: 220mW (16Ω, high gain)/120mW (32Ω, low gain)
  • Output 2.5mm: 320mW (16Ω, high gain)/200mW (32Ω, low gain)
  • Price: US$109.99



FiiO is a very well-established name among audiophiles the world over. The Chinese company was established in 2007 and has built up a reputation for affordable products with a high value ratio. You pay a budget price and get high quality equipment in return, which I think is why so many audiophiles have cut their teeth on FiiO equipment when they started out in the hobby, with DAPs such as the venerable X1, X3 and X5. By now FiiO has expanded to include higher end products as well, such as the X7 mkII DAP. They also expanded into IEMs where FiiO again look to set the value bar increasingly high, most recently with the release of the FA7 IEMs, where FiiO have made optimal use of 3D printing technology for mass production. This technology can help push down the price and maintain a consistent quality in large batches, as well as some of the other advantages 3D printing brings (e.g. allowing more intricate designs).

For me it was apparently only a matter of time before I too gravitated towards FiiO. The audiophile bug has well and truly bitten me, and I spend a lot of time listening to music, reviewing gear and generally just have something stuck in my ears all day long, be it IEMs or earbuds. The main downside of that, I discovered, is having a DAP (my AK70) with only an 8-10 hour battery life that is impossible to use when charging because of the noise that creates. It could theoretically be used as a USB DAC, but there too I found things to be far from optimal. Since I do a lot of listening behind my desk, I started wondering about a desktop solution. Being an audiophile that quickly escalated into plans for silly expensive equipment I did not have the money, getting that all too familiar look from the missus and seeing her hand slowly reaching for the frying pan.

So, in the interest of self-preservation, I felt it was high time to be sensible and consider an option that would make for a good introduction into desktop gear without breaking the bank. That is also the way I will approach this review. I am very much a music lover and don’t generally delve into the technical aspects of the gear, so I am not going to be the right person to compare technical specs. My aim here is to write for those who, like me, want to upgrade their desktop specs in a simple and affordable way. That is what attracted me to the K3. From what I saw the K3 is a tiny and elegant solution that offers FiiO’s trademark high value ratio and is intuitive to use. If that does not sound attractive to the desktop solution initiate, I don’t know what does. So, let’s see how it all worked out in practice.


The packaging of the FiiO K3 is very much a ‘no nonsense’ affair. It comes in a white box that keeps the DAC/Amp securely in place and added are only the bare essentials such as the data cable, 2 sets of anti-slip pads (only one set pictured, as I had the other set already installed on the K3), a quick start guide and warranty card. Simple, effective and you really don’t need all the fluff, especially at this price point.

Build quality.

The first thing I noticed when I took the K3 out of its box was how solidly it was built. It is a small and light device, but the black CNC’ed aluminium body feels very solid in the hand, not fragile or cheap at all. It looks quite elegant and I like it sitting next to my MacBook Pro. The switches are quite small, yet easy to reach even with earphones plugged in and they have a nice light ‘click’ to them when switching, so it does not require a lot of force, nor is it easy to accidentally switch them. The volume wheel that also acts as the ‘on/off’ switch feels very nice. There is a healthy bit of resistance and a lot of smoothness that helps to make precise volume adjustments easy, even with sensitive IEMs, and avoids accidentally changing the volume if you brush against it. The body is a little light relative to the resistance in the volume wheel, which is placed quite far to one side (right), so with one-finger operation you might end up flipping the K3 rather than turning the volume up (no such issue turning down the volume). When I operate it, I usually just use my thumb on the other side (left) for stability, which I do intuitively anyway and then one finger can easily switch the K3 on and control the volume very precisely.


On the front we find (from left to right) a 2.5mm balanced out, 3.5mm Single Ended out, bass switch, gain switch and volume wheel. The switches are simple with only two options, low gain or high gain and bass boost on or off. Around the volume wheel is an RGB light indicator that changes colour depending on the sampling rate. Blue light for 44.1 or 48kHz, yellow to indicate above 48kHz and green for DSD. Once I also got a red light, which I suspect was just the K3 telling me I was being an idiot for plugging it into my PS4 (more on that later).


On the back we find (from left to right) a 3.5mm line out, USB type C port, Coax out and optical out. Above the USB type C port is also a USB mode switch that allows the user to choose either USB Audio Class 1.0 or USB Audio Class 2.0. The difference between the two is that USB Audio Class 1.0 is limited to files up to 24- bit and 96kHz, whereas 2.0 will go up to DSD256 and 384kHz. For Mac OS users it is easy, as Mac supports 2.0 without the need for installing any additional drivers, while Windows users will need to install those. They can be downloaded freely from FiiO’s support page:


Page 2 – Connecting, Sound, and Conlusions.

2 thoughts on “FiiO K3 USB DAC/Amp

  1. Hiya,

    I’ve the 2015 MacBook Pro.. and tempted to buy this. Just bought some Grado Labs SE80e’s.. I just feel the MacBook is a little underpowered but mostly the sound is a little muddy and lacking somewhat.

    Did you find that was the issue prior to your purchase too?

    Many thanks,



    1. Hi Tony,
      My Macbook Pro is a little older (late 2011) and so the specs might differ, but I also found that it lacked a bit in performance even with easier to drive IEMs (sensitive IEMs also hiss quite badly). The K3 is definitely a noticeable, yet still affordable step up in my opinion.



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