USB audio on the go!-FIIO---BORN FOR MUSIC

Pros - budget price, small size, wide soundstage, sound improvement over my laptop HO

Cons - doesn't support smartphone connection (android)

I would like to Thank FiiO for providing me with a review sample in exchange for my honest opinion.

Manufacturer website: http://www.fiio.net/en/products/48

Is there an audio product that FiiO doesn't have in their portfolio? How about a micro-sized USB DAC/amp? Well, now they got one of those too, a brand new FiiO K1 usb dac/headphone amp. This is not the first thumb-drive size usb dac/amp I've tested, but certainly the first one I have seen at such low price. When it comes to FiiO, making more affordable products doesn't mean sacrificing quality, and K1 is no exception. So let's take a closer look to see what I have found.

Unboxing and accessories.

FiiO took a different approach with K1 where using a clear plastic packaging allows you to gaze right through the box to see the exact size, shape, and ridged surface of K1. You no longer have to guess what's inside or try to figure out if the image printed on the cover is up to scale.

Included accessories are a short usb to micro-usb cable, warranty and user’s guide, and a removable plastic clip. There is no battery since K1 works right off usb bus power. Also, I'm not sure if plastic clip was really necessary. Coincidentally, I'm reviewing their new small M3 audio player, and have the opposite comment where I would rather see a removable clip on M3 rather than K1. I mean, it's a removable clip after all, and can be easily detached, but I don't see the point of it.

The clip.

Design.

Weighting only 10g (w/o a clip) and with dimensions of 50mm x 20mm x 8mm, this is one tiny lightweight device dressed in all metal sandblasted titanium color shell with a ridged surface. One side of K1 has micro-usb connector and two small pentalobe (iphone style) screws. The other side has 3.5mm TRS headphone output and led to indicate the power.

Under the hood you will find TI PCM5102 DAC which supports audio up to 24bit/96kHz, TPA61332A driver, and Savitech SA9023A usb receiver to decode usb audio. It paired up and worked flawless with my laptop, but it didn't work with my smartphone (neither Note 4 nor Galaxy S5). That's probably the only real downside for me since I know about another usb dac with the same usb receiver where according to people's comments it's capable of being connected to a smartphone through usb-otg port. I know it's a bargain, but considering small footprint and sound improvement over my laptop stock sound chip, I think it would have been an ultimate gadget if it would support smartphones as well.

USB DAC connection.

Current draw (40mA idle, 50mA under a full load).

Sound impression and comparison to other USB DACs.

FiiO K1 has a dynamic sound with a nice separation/layering and a decent resolution, excellent soundstage expansion with a very impressive width. The sound is very crisp/detailed, and has a good top/bottom extension.

In comparison to $40 K1, here is how other portable usb dac/amps stack up:

HRT dSP ($70) - in comparison to K1, the sound is flatter, not as dynamic, soundstage shrinks in width, and you lose some transparency and resolution.

Astrapi ($130) - in comparison to K1, Astrapi has a very similar dynamic sound, similar layering/separation, soundstage is as wide but has a little more depth/height, overall sound is a little bit thinner, doesn't have as much body as K1, and sub-bass doesn't go as deep.

DragonFly 1.2 ($148) - K1 has a touch wider staging, a little brighter, crispier sound, while DF is smoother with more body, deeper bass. Similar retrieval of details, and a similar dynamic sound.

FULLA ($79) - FULLA is a little smoother, has more body, has a similar soundstage width and more depth/height. Overall sound is tighter and has more transparency in comparison to K1.

Despite its spec suggesting to be able to drive up to 100 ohm headphones with a power of > 75W (16 ohm load), I had no issues driving my demanding 320 ohm VE ZEN (very dynamic, layered sound), though trying 470 ohm ATH-R70x wasn't as good (sound was a bit dull and flat). It definitely was a huge improvement over my laptop HO, pairing up great with most of my headphones and providing a noticeable expansion in soundstage width, making sound crispier, more detailed, and more transparent. As a matter of fact, I fount it to pair up better with neutral and warmer headphones, while sounding a bit thin and peaky with some bright and analytical sound signatures.

Conclusion.

It looks like FiiO continues to push the envelope of price/performance ratio, and K1 is another prime example of that. Relative to my laptop (a few year old ThinkPad T430s), sound improvement was noticeable, though I don't guarantee it will be on the same level of improvement with every computer or laptop. What's important here is an increase in power to be able to drive more demanding headphones with ease, and also to be able to enjoy your efficient headphones with a sound improvement as well. I would have loved to see USB-OTG support to be able to connect K1 to my Android smartphone (can't speak for iPhone). I hope that FiiO will consider supporting this in the future. Other than that, this is one cool little audio gadget for under $40.