FiiO K1 - Portable Headphone Amplifier & DAC

MY IMPRESSIONS:

I got my K1 primarily to use with my XMG custom gaming laptop (from 2013) which has the Realtek ALC892 codec.

Honestly I wasn’t expecting much improvement but it’s definitely noticeable, the upper frequencies are sharper, mids have become silkier and low end is more refined. Overall sound resolution and musical detail has improved noticeably over my built in sound codec. I totally recommend it to anyone looking for a better sound from their laptop.

Conclusion - amazing thumb sized DAC with top notch internals for the price!

I wouldn't buy this if you think its gonna be fully compatible with your Android phone, because chances are its gonna take a lot of fiddling to get it to work. So if you want it for this purpose then look elsewhere, however some people on Head-Fi have managed to get it to work with their Nexus 6P and Galaxy S6 (using a usb hub)

In Windows its plug and play with no other drivers required.

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Lifted.

BACKGROUND

After selling my Fiio E11k and my Fiio E12, I missed having a portable amp. Not that majority of my headphones need it, but one in particular need amplification – the JVC HA-RX700. Needless to say, it’s still my favorite headphone. With a smartphone, you need to get to more than 70% of the volume to at least get some needed impact. Otherwise, they’d sound lazy. Yes, lazy. Given their low impedance, you might think they’re easy to drive. They’re not. With a DAP like the Fiio X1, they could be. But even then, I feel the need to add some amplification. Long story short, I went for the Fiio K1, and only by accident. I originally purchased a pair of Grado G-Cushions from the store. Since I didn’t like the sound signature they produced with my Grado SR80e (too treble heavy, even for me who is not treble sensitive). I decided to exchange the item and since they’re about the same price, Fiio K1 it is! Let’s begin.


ABOUT ME

I listen to almost all genres of music but my favorites are rock, blues, and jazz.

I am a music lover, not an audiophile. I need to veer away from the audiophile persona from now on. I love music more than the equipment to play music with. I recognize that decent equipment is important but decent is good enough. Expensive is not necessary. I’m not willing to go past the $100 mark for any reason. I firmly believe in the law of diminishing returns.

I believe in burn-in but it depends on the headphones or the gear. Some do not need much. Some do not need any at all.

I believe in measurements but I never relied on them. I solely rely on my ears.

I believe that blind test is the only real test, without any visual influence or biases, without placebo.

Audio nirvana for me is a state of mind, not a state of equipment.

Regardless of my beliefs, I respect all audiophiles and music lovers for their passion and dedication.


PACKAGING

Here are the pictures of the basic packaging and the DAC-amp itself. It’s a nondescript packaging and that’s everything you need for a desktop set-up. For smartphones, you will need an adapter or a micro-to-micro male OTG cable (Android). For Apple users, probably a lightning cable or adapter (I’m not familiar with Apple products. I never used them.)



SPECS AND FEATURES

For complete specs and features, please check here - http://www.fiio.net/en/products/48.


BUILD QUALITY, DESIGN AND FUNCTIONALITY

I would say pretty solid. It’s tiny but it looks good in gray. It’s not the usual Fiio-black but the look is refreshing. It’s very simple – You have the micro USB input jack on one end and the 3.5mm output jack on the other.

• For PC – It’s plug and play. Windows will take care of installing the needed drivers. You just need to set it as the default device in Control Panel > Hardware and Sound > Manage audio devices. You can also set its Properties to receive the highest bit depth and bit rate it can handle (96khz/24bit). I haven’t tried custom drivers as Windows drivers work just fine.
• For Android – You can either purchase a micro-to-micro adapter or a mini-adapter like in the picture below and you can use that for the stock cable. I’m using Stellio player for Android and it’s not finicky. It’s basically plug-and-play. After plugging, the K1 lights up and you’re good to go. A word of warning – since it’s bypassing your phone’s DAC and amplifier, it amplifies everything, including message tones and ring tones and they sound really really loud. You may want to put your phone in vibrate mode or silent mode just to protect your hearing. It disturbs you abruptly too if a message or a call comes in. It’s not a pleasant experience.

(If you’re interested on how Stellio performs, I posted my thoughts on this thread - https://www.head-fi.org/threads/best-android-music-player-app.638387/page-38#post-13911402).


SOUND

Burn-in: Honestly, I don’t think it benefits an amp the way it benefits a headphone. Nonetheless, I’m writing this after a few months of use so it’s burnt-in reasonably.

SET-UP USED:

• Lenovo K4 Note Smartphone (with Wolfson 8281 Audio Hub)
• Dolby Atmos engaged (gives a more accurate perception of soundstage (applicable only to headphones)
• Stellio music player EQ is off

Smartphones, even the best sounding ones, are inherently warm sounding or have at least a warm tilt to them. I believe this tuning is best intended for the masses and majority of people prefer this sound signature. Now the DAC in the K1 is a very capable one (Texas Instruments’ PCM5102). It’s the same DAC in the venerable Fiio E17K. The 5102 is a neutral sounding DAC, especially compared to the usual DACs in smartphones. It’s the same effect I got when comparing the sound to the Wolfson house sound of my phone. It’s noticeably leaner and you hear it immediately, there’s no second guessing. It’s akin to taking off the “fat” from your music. And the effect is a livelier, faster, and a more energetic listen.

Regarding other aspects of the sound (bass, mids, highs, soundstage, and imaging), I believe in the wisdom of our good friend Brooko. This is not affected by an amp or a DAC-amp for that matter. It’s in the headphones being used so I will not comment on those. What I will say though is an amp will most definitely have an effect on clarity, especially if the driver needs it (medium to hard-to-drive loads). If the headphone driver is moved by sufficient power, it will definitely sound not only louder, but clearer.


WHO WILL BENEFIT FROM THE K1?

First and foremost, this is intended for desktop users as the product page suggests. If you are able to use it with a phone like me, you’re in luck. If your phone is OTG capable without too much bloatware or as close to stock Android as possible, it will most likely work. Otherwise, I suggest you try before you buy.

Now let’s get one disadvantage out of the way – pops and crackles when plugging to a smartphone, especially on some quiet parts of a song, not isolated to the beginning or the end. This has been reported by several users and I have experienced the same. There are several threads addressing this issue and it’s not isolated to the K1. It’s a problem for even the higher-end DAC-amps:

• https://www.head-fi.org/threads/fiio-k1-has-problems.827559/
• https://www.head-fi.org/threads/strange-issues-with-fiio-k1-dac.843799/
• https://discussions.apple.com/thread/7685241

What might help though are the following:

• Change the audio buffer size of your phone. This feature is available in Stellio and after measuring my phone’s buffer size capability (Try this app. It works well - https://play.google.com/store/apps/details?id=com.levien.audiobuffersize&hl=en), I changed it and there is some improvement but it’s still prevalent in some songs.
• Turn off wifi or data usage. This could also be EMI. It helped to some degree but again, not on all tracks.
• Change the cable. There are higher quality micro-to-micro or lighting cables out there. I haven’t tried something expensive since I have a decent one from a local store. I imagine something like this might help but it pays if you could audition one - https://www.amazon.com/Cable-Micro-Crystal-Silver-ZY-058/dp/B00MTB760K.
• No one actually had a definitive answer and I’m not buying that it’s solely a software problem like what’s being discussed in the Apple forums. Trial and error might work or better yet, have your K1 replaced if it’s under warranty and check if it’s the same for the replacement. I don’t believe it’s defective though since it works fine with PC.

CONCLUSION

For such a tiny device, I would easily recommend the K1. Its main strengths are extreme portability and ease of use. It’s practically plug-and-play from any source and it has enough power to drive up to moderate loads. You don’t have to worry about charging batteries and it doesn’t drain too much power from the source based on personal experience.

Then again, if you’re main purpose is finesse and power to drive heavy to heavier loads, I would suggest the likes of the Fiio A3 or the A5. Comparing it directly with the A3 in high gain, the latter starts to pull away in terms of power and just sheer cleanliness of amplification.

Sonically, if you want a significant change or improvement in sound signature, you’re better off getting a DAC-amp like the K1. A pure amp like the A3 would not alter the sound signature of the source. That is innate to the source’s DAC. Using a different DAC like the K1 will give you this benefit. And it does deliver a neutral and energetic listen. For the price, it’s a total steal! Fiio has a winner in this little gem!

Happy listening, everyone!

It’s nice to be back!

INTRODUCTION

There has been a plethora of different budget friendly smart-phones, tablets, and ultra-portable laptops which may not have a lot of money invested into the audio portion of the hardware. So what do you do if you're not satisfied with the audio – even though you may love many other factors of your portable device? The solution of course is a USB DAC/amp which you can plug and play to gain an increase in sound quality. And there have been a lot of these devices released recently. So what to choose? The prices can range from under $50 to more than $250!

FiiO released the K1 ultra-portable USB DAC/amp last year, and up until now I haven't really had a chance to complete my write-up if this little device. So lets put this $40 device through its paces and see where it sits among the competition and if its worth considering.

ABOUT FiiO

By now, most Head-Fi members should know about the FiiO Electronics Company. If you don’t, here’s a very short summary.

FiiO was first founded in 2007. Their first offerings were some extremely low cost portable amplifiers – which were sometimes critiqued by some seasoned Head-Fiers as being low budget “toys”. But FiiO has spent a lot of time with the community here, and continued to listen to their potential buyers, adopt our ideas, and grow their product range. Today, their range includes DAPs, portable amps, portable dac/amps, desktop dac/amps, earphones, cables and other accessories.

FiiO’s products have followed a very simple formula since 2007 – affordable, stylish, well built, functional, measuring well, and most importantly sounding good.

DISCLAIMER

The FiiO K1 USB based portable amplifier and DAC that I’m reviewing today is supplied by FiiO completely free of charge, and is done so for the purpose of providing a review. I don't receive any payment or incentive to provide the review – but I do get to keep the sample.

I have now had the K1 for more than a year, but I don’t really use it regularly. The retail price at time of review is USD 40.

PREAMBLE - 'ABOUT ME'. (or a base-line for interpreting my thoughts and bias)


For the purposes of this review - I used the K1 mainly with my iPad Mini, my PC and old Asus laptop (as DAC).

This is a purely subjective review - my gear, my ears, and my experience. Please take it all with a grain of salt - especially if it does not match your own experience.

WHAT I WOULD LOOK FOR IN A PORTABLE DAC/AMP
This is what I would look for in a portable DAC/amp. This is useful to remember when looking at my scoring later in the review.

• Be genuinely portable => great build and small size
• Be reasonable in either battery life or drain on the host
• Be an improvement sonically over the original source
• Clean, linear signature
• Easy to use
• Able to drive both low impedance and (within reason) higher impedance cans
• Value for money

PORTABLE AMP/DACs I HAVE EXPERIENCE WITH
Previous = FiiO E7, Nuforce U-Dac3, RHA L1, Beyerdynamic A200P
Current = FiiO E17K, Q1, Q1ii, iFi Micro iDSD, IMS HVA

ULTRA PORTABLE AMP/DACs I HAVE EXPERIENCE WITH
Current = FiiO K1, i1, Cozoy Aegis, Cozoy Takt Pro

THE REVIEW

PACKAGING AND ACCESSORIES

The K1 arrived in a very basic clear plastic retail box. In the top third of the box is a small cardboard inner box which houses the included documentation, a plastic clip and a short USB to USB micro cable. The packaging is decidedly “budget”, but then again, so is the “no frills” market the K1 is aimed at.


Probably the only thing I thought was missing was a short micro-USB to micro-USB cable, but as you'll see later in the review (connectivity options), you'll appreciate why I no longer see this as necessary.

TECHNICAL SPECIFICATIONS
For this section I've included comparative data on FiiO's older original Q1 which currently retails for ~USD 55.00. Its also a DAC/amp (not ultra portable – but necessary for comparison being similarly priced.)

BUILD
The K1 is rectangular shaped with nicely rounded edges on the main body. The main body has a subtle ridged design which makes it easy to grip. The top panel houses the 3.5mm headphone out and a blue LED light which glows when operating. The bottom panel houses the USB socket. Both sides have a groove to house the removable plastic clip.

Small and neatly finished	The removable plastic clip

Internally the K1 uses a Savitech SA9023A USB receiver combined with TI's high fidelity low noise PCM5102 DAC chip. Amplification is undertaken by the TPA61332A on-board amplifier.

Tiny compared to the iPhone and FiiO Q1ii	Blue LED when in operation

HEAT AND POWER

The K1 doesn't heat up at all, and is quite cool to the touch even after a few hours playing.

In terms of power output, the specs say that it'll put the following output into these loads:
Into 16 ohms = 75 mW
Into 32 ohms = 35 mW

FiiO suggests headphones with impedance up to 150 ohms max – mainly due to the relatively weak amplification. My first task (using my old ASUS eeePC and work MS Surface laptops) was to find out how much gain the K1 would deliver over and above the on-board sound-cards. So I simply used the quite demanding MEE Pinnacle P1 (50 ohm / 96 dB sensitivity), and took a couple of measurements with my SPL meter.

With my Asus eeePC running either Linux or Windows, the internal sound-card. was weaker than the K1 by around 14 dB when played at full volume (with the internal sound-card only managing a paltry 84 dB at max volume). With my work laptop (an MS Surface) the internal sound-card. was a lot closer to the K1's output with only about 4 dB difference (in favour of the K1).

Easily handled the MS Pro and HD630VB	Underpowered with more demanding headphones

In the case of the P1, I was able to get adequate volume from the K1 (with both Surface and eeePC) at a volume level of around 25-30% for my usual ~ 65-75 dB listening level. I also tried my 320 ohm VE Zen2, my MS Pro and HD630VB, and everything I threw at it seemed to be handled pretty well.

When it came to the 300 ohm Senn HD600 or HD800S, while I could get the volume loud enough, they were clearly being underpowered (loss of bass and general dynamics). It wasn't unexpected, and I have to admit FiiO got their range right here. If you stick with IEMs and relatively easy to drive dynamics, you'll have no issues.

SONIC PERFORMANCE

Preface
I’m going to preface this section with a little critique I received a while ago (by PM), and my answer to it – so that you can understand why I don’t comment on some things, and why I do comment on others. I was told my review on another amp was poor because I didn’t include sections on bass, mid-range, treble, sound-stage, imaging etc – yet referred to an amp as warm, full, or lean.

Now I can understand the reference to warm / full / lean – as they are very subjective terms, and whilst I’d like to avoid their use, they are invaluable to convey true meaning. Comparing my NFB-12 to the Aune X1S for example – the Audio-gd does sound richer and warmer. It’s the nature of the DAC which is used.

But I choose not to comment on bass, mids, treble, and most definitely not sound-stage – simply because when we are talking about a DAC/amp – IMO they shouldn’t be discussed. An DACs job is to decode the signal in as linear fashion as possible, and the amp’s job is to amplify the signal with as low distortion as possible. Basically you should be aiming to output as linear signal as possible. If the device is doing its job properly, there is no effect on bass, mids, or treble – except if hardware boost is concerned. And IME an amp does not affect sound-stage (unless there is DSP or cross-feed in play) – that is solely the realm of the transducers and the actual recording.

So we have that out of the way how does the K1 perform sonically?

Tonality
For those interested, FiiO does show graphs of the K1 under load, and it is very linear from 20 Hz – 20 kHz, with a very gradual drop off in the upper treble (around 0.2 dB) with the main part of this drop occurring from 10-20 kHz. At that very slight level, we won't really hear it. I could have measured this myself – but in this case I know FiiO's Audio Precision set-up is a lot better than my hobbyist gear.

FiiO’s Measurement	Small device, clean sound

I listened and compared it to the E17K (one of the most linear devices I own). In subjective comparison, the K1 is very similar with perhaps a hint of warmth / fuller tonality than the E17K. So what does this tell us? Simply that the K1 supplies reasonably linear, and very clean output. Purely subjectively, it sounds pretty neutral and to my ears, ever so slightly on the warm side of neutral. It does have a reasonably clean background which creates a good sense / perception of space.

Format Support
I've tested with PCM up to 96/24 and the K1 has had no issues natively decoding.

In Comparison To The On-board Sound-cards
With the Asus eeePC, its an older model, and the sound-card was never very good on it. Its on the noisy side, and will regularly pop or cut-out. With the K1, the difference was easily noticeable – sound was a lot more consistent, and there was a sense of more space and separation of instruments with the test tracks I used. Sonically the K1 also delivered a richer overall tonality, and gave a sense of higher resolution.

With the Surface, the two were a lot closer, and the differences far smaller. Overall the K1 still gave the sense of a slight improvement, but it wasn't as noticeable as with the eeePC. This is all very subjective, and whilst I'd relatively easily pick the Asus from the K1 in a blind test, I do feel the Surface might be a lot harder (and fear that maybe the differences are purely imagined on my part).

CONNECTIVITY

Laptops / PCs

Testing with a variety of sources	Plug and play with the Surface

Using both the two laptops, and also my desktop, the K1 connected and set-up without any need for additional drivers (both under Linux and Windows). As FiiO states, this is simply a plug-and-play exercise. And that makes it ideal for something like a work machine – especially if you're hamstrung by an IT department who don't like you installing things like extra drivers.

Tablets
I'm guessing you'll have no issues with windows based tablets, and unfortunately I couldn't test it on an Android based device. I do have an iPad Mini I use regularly though. And with a camera connection kit, the K1 was recognised straight away and I was up and playing very easily. Was it an improvement over the iPad's default on-board sound? That's a really hard one to answer. Again it was a slight increase in overall volume, but after volume matching the two were really close (the iOS devices have always been very linear). Once I'd volume matched properly, there seemed to be very little between the two. But it was gratifying to have the option (with the camera kit). I did try some other lightning to micro-USB cables, but the only that would work was the L19 cable.

No issues with the iPad	And also with the iPhone (and camera kit)

Smart-phones
I first tried my wife's Galaxy, but the K1 wasn't going to play ball no matter what I did. I also tried FiiO's own X5iii and X7ii (both being Android devices) – their Q1ii managed to work with both recently so I was hopeful but unfortunately disappointed. I think with Android you are always going to be a bit hit and miss.

With my iPhone SE, I was originally disappointed – none of the cables seemed to work (including FiiO's cable included with the Q1ii). The L19 did work though, and so did the camera connection kit. Again the sonic differences with iPhone SE were slight (the SE seemed ever so slightly brighter without the K1) but it was practically unnoticeable (subjectively). While it was nice to have the option, its not one I'd probably feel the need to use.

EMI / RFI
Thankfully there hasn't been any issues, and that’s despite having the iPhone and iPad streaming (there was no sync issues either – video vs audio). And in this regard, the K1 does seem to perform really well.

Power draw
Because it doesn't have its own battery / power source, this is always going to be somewhat of an issue with a device designed to be used portably. With the K1, my testing seemed to indicate that for laptops you're not going to really notice the power draw (the K1 is sipping rather than gulping). This was similar with the much larger battery on the iPad Mini its hardly noticeable. With the iPhone's smaller battery, I'd estimate that battery usage might have increased by around 10% using the K1, but again that’s not what I'd call a huge issue (for me anyway). YMMV.

COMPARISON WITH OTHER DEVICES

I thought at this stage it would be a good idea to try and compare the K1 with some alternatives. My prerequisite was that the comparable units should all be portable DAC/amp devices which would work with my iPhone, laptop and tablet – so I’ve used a mix of similarly price amp/dacs, and somewhat more expensive ultra-portable USB devices from Cozoy.

I tested the K1 against my FiiO Q1 original (currently USD 55), FiiO E17K and FiiO Q1ii (both USD 99), Cozoy Aegis (~ USD 299) and Cozoy Takt Pro (~ USD 289). For testing I’ve used my iPhone SE, headphone out of the device in question, and my Sennheiser HD630VB to evaluate. All devices were volume matched with my SPL meter at 1 kHz with a constant test tone.

FiiO K1 (~USD 40) vs FiiO Q1 original (~USD 55)
These are both in the same price bracket. The K1 is the ultra portable, while the Q1 is the portable. Both have FiiO's very good build. The K1 has the benefit of size (you'll hardly notice it is there) – the Q1 has the benefit of features (bass boost, gain, volume pot, power output, can be used as stand-alone amp, and own battery). Both are immediately recognised by my Linux set-ups, both work with the iPhone and iPad, and both also work as driver-less solutions to my two Windows based laptops.

In terms of sound, the Q1 subjectively is very slightly richer in tonality with a better (darker) background and more sense of instrument separation. Both are an improvement on the eeePC's default sound-card. The power output is a huge bonus too, because with the Q1 you can also drive an HD600 to respectable levels of volume and quality.

Really this one is a no-brainer for my preferences. Unless you need the ultra-portability, the Q1 original is the far better device (IMO).

K1 vs Q1 original	K1 vs E17K

K1 (~USD 40) vs FiiO E17K (~USD 99)
I should preface this to say that the E17K is still my favourite Swiss army knife for a portable amplifier. I terms of price bracket, the E17K is more than double the price of the K1, and really they are targeted for different uses. Again the K1 is the ultra portable, while the E17K is the portable. Both again have rock solid build quality. The K1 has the benefit of size (you'll hardly notice it is there) – the E17K has the benefit of features (tone controls, gain, volume pot, power output, can be used as stand-alone amp, and own battery). Both are immediately recognised by my Linux set-ups, both work with the iPhone and iPad, and both also work as driver-less solutions to my two Windows based laptops.

In terms of sound, the E17K is subjectively the more linear of the two devices, and with its easy to use tone controls, you can make it warmer or brighter with any ear/head-phone. Again to me it has a better noise floor and more sense of instrument separation. Both are an improvement on the eeePC's default sound-card. The extra power output of the E17K is a bonus allowing more versatility in head-phone choice.

Given my choice, I would personally save for longer and buy the E17K. Its feature set provides far better value for money. But we are talking about very different devices here, and if $40 is all you have, the the K1 still provides an incremental gain for comparatively little monetary outlay.

FiiO K1 (~USD 40) vs FiiO Q1ii (~USD 99)
Again the Q1ii is in a different price bracket, but I consider the comparison valid, simply because they can both be considered portable enough for use with smart-phone or lap-top. The K1 is the ultra portable, while the Q1ii is the portable. Both are built incredibly well. The K1 again has the micro size, while the Q1ii has the benefit of features (bass boost, gain, volume pot, power output, balanced out, plays more formats (including DSD), can be used as stand-alone amp, and own battery). Both are immediately recognised by my Linux set-ups, both work with the iPhone and iPad, and the Q1ii works as driver-less solution on the Win10 Surface, but requires a driver for the Win7 eeePC.

In terms of sound, the Q1ii subjectively is very slightly richer in tonality with a better (darker) background and more sense of instrument separation. Both are an improvement on the eeePC's default sound-card. The power output again is a factor, and if DSD is your thing, it will offer more options. The one draw-back the Q1ii has is an issue with EMI/RFI causing static feedback with the iPhone (I haven't noticed it with the laptops).

K1 vs Q1ii	K1 vs Cozoy Aegis and Takt Pro

FiiO K1 (~USD 40) vs Cozoy Aegis (~USD 299)
Now we move into the ultra-portable vs ultra-portable, but this time we're talking a whopping difference in price. Both have a fantastic build quality, but the Aegis does come with more accessories (cables) and seems to have better connectivity options with both Android and iOS (you never have to jump through hoops - it just connects). The Aegis does have resolution up to 24/192. With Win 10 it is plug and play, but with Win 7 you have to load drivers.

Before we get to sound there are a couple of other factors to consider. The Aegis does get a little warm (it is more powerful than the K1 and does have a higher gain), but has a consequently much higher draw power on the source (it will drain an iPhone battery over the course of 4-5 hours). Because the gain is set very high, you also need additional volume control (so with iOS this means using an app with a pre-gain control). Both are fairly big drawbacks unfortunately.

Sonically the two are also quite different. The Aegis has more richness to its tonality, but also seems to have more overall resolution (ability to really bring out high level detail). The K1 is still very good, but the Aegis does seem to take things to a slightly higher level.

So in terms of overall use, what are my thoughts? In this one (for me with iOS, Linux and Windows use) the K1 wins (YMMV with Android). It is cheaper, is still very good sonically, and doesn't have the issues with power draw or volume control. You won't have the same power output (higher gain), but for a device to be good, it has to be versatile, and in this case the K1 delivers a little better.

FiiO K1 (~USD 40) vs Cozoy Takt Pro (~USD 289)
Another ultra-portable vs ultra-portable, and I left this one to last because I've only had the Takt Pro for a couple of weeks. There is another big price difference, but this time the Takt Pro has a few more features up its sleeves. The Takt Pro comes with more accessories (cable choices), and again has the better connectivity options with Android and iOS (you never have to jump through hoops - it just connects). The Takt Pro has resolution capability up to 32/384 and also DSD. With Win 10 it is plug and play, but with Win 7 you have to load drivers.

In terms of build, the Takt Pro is actually even smaller than the K1, and has the added benefit of on device volume and playback control. This works with iOS, Windows and Linux – and is implemented really well. Unfortunately Cozoy don't advise actual power output, just voltage – but using a calculator I was able to determine that Cozoy's 1.5V RMS equates to about 25-30% more power than FiiO's 3.25 Vp-p. In terms of power draw, I haven't been able to calculate this fully – but it appears that the Takt Pro does draw a little more power than the K1 (expected with the power output), but doesn't seem as hungry as the Aegis. In terms of actual real-world power output, the Takt Pro does a fairly reasonable job with the HD600 where the K1 struggles.

Sonically the two are again quite different. The Takt Pro has more richness and depth to its tonality, and definitely seems to have more overall resolution (ability to really bring out high level detail). The K1 is still very good, but the Takt Pro does seem to take things to a higher level, and enough that I'm quite blown away at how good this tiny device sounds.

So again in terms of overall use, what are my personal thoughts? In this one (for me with iOS, Linux and Windows use) I'd actually be more inclined to save for the Takt Pro (I really like it). If it doesn't fit your budget though the K1 is still an improvement on a lot of basic audio set-ups.

VALUE

This one is probably an easier one to call than most. The K1 delivers good value for a no frills audio device. It does what it claims to (an increase in audio quality), and does it well. Are there better value options out there? Yes – given the choice, I'd still plug for the Q1 original being a better overall option, but it doesn't stop the K1 being a pretty good device for very little outlay.

FIIO K1 – SUMMARY

The K1 is a bit of an enigma to me. At its heart it is a very good value (only $40!), well built device which does very little wrong, and does deliver a genuinely better audio performance than some of the cheaper on-board solutions in cheaper laptops. It is definitely an improvement on my old Asus eeePC.

Its also pretty much a driver-less solution which is agnostic of device, although the 3 Android devices I tried to test with simply would not connect. So with Android I'd advise a little caution (check reviews and see if anyone else has had success). With Windows the connection is simple and painless. With iOS, if you have a camera connection cable, you're all set.

It is relatively weak on power (only 1.2 dB overall gain), but the K1 was never really about power and more about quality anyway. It offers a pretty neutral / linear overall tonality, but maybe with the faintest hint of warmth. Resolution and noise floor seems decent – especially at this money, and there seems to be no issues with EMI/RFI.

For its asking price, its a decent offering – I just personally think the Q1 original gives you a lot more options for a similar price. And if anyone is actually thinking of using a K1 + A1 combo, just get the Q1. It is better value.

This was always going to be a hard one to rank – so I went back to my original thoughts on requirements for an ultra-portable, and tried to apply an objective rating (see table below). The end result – good value and sonically an improvement. A good solution for someone just getting into audiophilia.

I just want to close with thanking Sunny and the team at FiiO for arranging the review sample.

Scoring Chart

USB Ultra-Portable DAC/amp	FiiO K1			(out of 10)
	My Score	Out Of	Weighting	Weighted Score
Accessories	5	10	2.50%	0.125
Build and Design	9	10	5.00%	0.45
Power Draw	9	10	7.50%	0.675
Output Power	6	10	7.50%	0.45
Portability	10	10	7.50%	0.75
Overall Sound Quality	6	10	35.00%	0.60
Driver-less Solution	10	10	7.5%	0.75
Connectivity options	6	10	7.50%	0.45
Music Format Support	6	10	2.50%	0.15
On Device Controls	0	10	2.50%	0.00
Noise (EMI/RFI)	10	10	5.00%	0.5
Value	9	10	10.00%	0.9
TOTALS	86	120	100.00%	7.30