Fiio K9

Fiio K9

It's no secret that Fiio has been “ upping their game” with so much competition that promises a lot with modern day sources. Fiios latest DAC/AMP is not exactly the highest end DAC/AMP they make. That title belongs to the Fiio K9 pro ESS. However inquiring minds want to know. When looking at the spec sheet for the latest K9. It is strikingly similar to the K9 pro minus a bit of power. The K9 pro uses two flagship ES9038pro DACs, the new K9 uses two ES9068AS. Both use THX AAA 788+ for amplification and QCC5124 for bluetooth. Uses the same aluminum chassis, and very similar linear power supply. Question is, is this a case of Fiio giving the consumer something very close to their flagship product for cheaper or is it simply a brilliant move on Fiios end to do one better which ended up getting closer to their flagship?

A bit of a backstory about me and why I ended up getting a K9 pro ESS and now the K9 I have here to review. I do a lot of IEM reviews on headfi and so I am always on the lookout for sources to feed the hobby much like everyone else. My own philosophy in reviewing IEMs and headphones is that it is very important to use a variety of sources with different sound signatures to see how that particular IEM or headphone does with different sound profiles and power from various sources. This gives me a greater understanding of what the phones are doing vs the sources I am using. What type of sound creates synergy with an IEM and what doesn’t. Desktop solutions in my opinion are valuable as they provide more power for amplification and arguably some of the best sound quality for the bucks. Naturally I try all my IEMs I review but beyond that I am trying to replicate how a prospective buyer would use for said items I review. Hence the need for a greater variety of sources.

If you own a few dac dongles, an underpowered DAP or even worse you're using your phone as a source. Do not overlook a quality sounding desktop DAC/AMP. As easy to drive as most IEMs are, a lot of them really don’t come full bloom until you add some power with that quality sounding source. More times than not it is the desktop source with ample power and one with a good low noise floor will optimize an IEM sound to a level you're not aware of, until you try it. This is the reason why I amplify every IEM I review just to see if more power elevates its sound. Some types of IEMs scale to greater power better than others. Dynamic IEMs > Planars > Tribrids= hybrids> and lastly the all BA type. In this order generally benefit from amplification or more powerful sources.

It was when Fiio asked me to review their K7 DAC/AMP that surprised the heck out of me of what Fiio has accomplished lately with what they have plenty of experience at. The DAC/AMP. I was so impressed with the K7 and what it had to offer for the money that I went straight to the top and ordered me a brand new K9 pro ESS from Aliexpress during black friday sales last year. I was all too happy to splurge the money to buy Fiios top end DAC/AMP. And yes it paid off huge. To me, the Fiio K9 Pro ESS has better sound quality than all of my top end DAPs. No question the K9 pro ESS is my top sounding/reference source easily using my IEMs and CANs. It was the K9 Pro ESS that made me realize. It's not the expensive DAP that has the SQ for your IEMs. It is the desktop DAC/AMP. Case in point, the new K9’s sound quality. I doubt there is anything comparable for DAP or DAC dongles that comes close to its sheer sound quality and power. Yes, those other devices are portable and they have their uses. But I am talking about sound quality from a source. Quality and power for the money we are talking about. It is when you get to the kilobuck class for DAPs that you reach the sonic capability of the K9 and even then you're not exactly getting the clean power available from the K9.

With that I would like to thank Fiio for graciously offering me another gander at their handy work in the K9. You can read more about the K9 here on their official page and purchase one here on their official aliexpress page. Once again I was asked to test out the K9 and report to you good people all about the new K9. It has been used, burned in and tested by yours truly and my report here is the culmination of over a month of getting lost in my media from my laptops using a variety of IEMs and CANs I own. My review will also have a direct comparison to the K7 and the K9 pro ESS.

With the introduction of the new K9, it came to me as a bit of a surprise as it shares more than a few design aspects with the flagship K9 Pro and does a few things even better, 7 preset PEQ settings via control app for bluetooth connection. Higher DSD output DSD512 vs DSD256. One aspect I can share with you all. The K9 seems to be better cooled vs both the K7 and the K9 pro ESS. Could be due to the ES9068AS chips needing less power vs the ES9038pros in the K9 pro. And could be due to the much larger, more substantial chassis of the K9 in comparison to the smaller form factor in the K7.

It definitely runs cooler vs the K9 Pro ESS. Otherwise they both share a lot of similarities; the same aluminum alloy chassis, similar AC- built in linear power supply, QCC5124 Bluetooth chip. Same options for digital inputs and analog inputs, same output modes. While the K9 has less overall power vs the K9 pros. The power difference is not huge for the K9 vs the K9 pro. It will be safe to assume you should be able to drive whatever hard to drive CAN in your collection just fine with either of these sources. The other omissions from the K9 pro design that didn’t make it to the K9 is no MQA and the USB-C input on the side of the K9 pro. I have to admit this little feature was one I enjoyed a lot from the K9 pro as I can connect any of my DAPs via USB C cable directly to the K9 pro. Not a big deal as you can plug your player into the K9 in numerous other ways. Coaxial, optical, RCA in, balanced in which also works great or via bluetooth.


What you get.
Love how Fiio packages their larger DAC/AMPs. This is not a DAP you're carrying around; this thing has some weight and girth. It's all aluminum alloy chassis is 200x220x72mm or 7.9”x 8.7”x 2.8 inches thick. Weighing in at a hefty 2660g almost 6 pounds. It's inside their larger box when you get them new but the box itself is double boxed with foam inserts in between. That is how to ship one of these things. Opening the large black box yields the source itself. A rather short power cord. 6 sets of rubber foot nubs, 6.35mm male to 3.5mm female adapter, instructions and USB-A to USB-B cord to connect to your computers a replacement fuse and finally a plastic foot stand just in case you need to free up some space around the desktop by placing the K9 on its side.

One suggestion I have for Fiio is that they should include a power cord that is actually longer. The length of the power cord is 4ft or 1.21 meter, which is actually not long enough when you have the K9 next to your laptop on your desk and you have to plug into a wall or power outlet on the floor which is my case. Average desks stand around 3ft or a meter high in height. That leaves not much extra cord to get to the wall. I had to revert to using a longer cord I got from an old monitor plug to connect to the K9 as the one included is simply not long enough. The good news there is that these power cords are a dime a dozen and easy enough to change out. I would have preferred at least a 2 meter cord instead.

Most use case scenarios have you connecting the K9 via USB-B to USB-A to your laptop or music server. My windows 11 laptop recognized the K9 right away and uses a generic driver and I am off and running. You can download a dedicated driver for the K9 for higher bit rates and better stability via the Fiio download link here. You can use the K9 preamp function for active speakers on your desktop. Its connectivity options are numerous in that you can connect other sources to it. Your gaming console via optical. Use Bluetooth functionality to connect your phone or laptop and can change how the K9 sounds via preset EQ on Fiios control app. All of it functions through its outstanding sound quality.


Gaming/media on the K9. I am an avid gamer and having good audio for your gaming brings another level of immersion and here the K9 finds superb synergy with Fiios own FT3 headphones. Testing the sound performance with my current addiction. Diablo 4 on my gaming laptop. The difference between onboard sound vs the K9 is substantial. FT3 requires amplification as it is a 350 Ohm CAN. Once fed the necessary power, the FT3 has a well balanced dynamic tuning to its sound make up. The K9 feeding that ample power. The sound properties become fully dimensional. 3D sound processing is not a part of the K9 but it certainly sounds like it. Diablo 4 is a AAA title that took something like 20 years for the designers to make and has one of the best epic soundtracks and sound effects for any game. I can’t tell you just how fully blown the sound that comes from using the K9 and the FT3. It was meant to be. It is as they say. Once you go there you can’t go back. No way am I ever going to use onboard sound processing out of my computers. There is no comparison there. Fantastic for all media in general using the K9.

Movie watching, watching high-definition movies with the K9 processing its sound is how you want to watch movies on your down time. Pumped through speakers even better. K9 provides so much dynamism, better clarity and definition. It is funny to me that I used to think my onboard ASUS sound processing was decent. NOPE. Not by a mile. The K9 is a great companion for computers in general as it will bring a sound level you are not used to from your lame onboard sound.

Music listening/ Sound
The K9 is a prime example of Fiio giving the consumers more for what you're paying. As previously noted the K9s ability/ use/ and more importantly SQ comes dangerously close to the flagship K9 pro ESS. The benefit of folks that end up getting a K9 is that it was introduced well over a year after the release of the first K9 pro. The cost savings on paper is the use of a lesser ESS chip in the EA9068AS with a few minor omissions like MQA and USB-C connectivity and that is it. Everything else seems to be intact. Including the sound quality.

What you're essentially getting is a new DAC/AMP that is not exactly the same as the K9 pro ESS but not all that far off either, especially for sound quality. Here is what you wanted to know, the SQ difference is minor but audible with the K9 pro pulling ahead in a few aspects, instrument separation, dynamic range and imaging. Otherwise we are talking about identical sound qualities, its tonal and timbre characteristics, its sound layering, overall definition with identical balanced tuning carried over from the K9 Pro topology.

Fiios base sound signatures are always neutral especially the more mature the product range is the more balanced neutral the performance is, however in utilizing some of the best audio chips and amplification in the industry. An extremely low noise floor is achieved which brings some of the cleanest black space for a background for your music. This matters as you get a level of transparency from your tracks that is “better” than what you normally hear that same track with by any other method. Where SQ matters is just how dynamic your tracks can sound using the K9 and this is what the recent Fiio DAC/AMPs all have in common. The K9 has a superb clean sound quality and when I say clean I don’t mean bright or warm. Just clean meaning your tracks sounds like what it was meant to sound like with every tonal character, precise imaging, a higher level of layering in check depending on how your music was engineered. Superior transparency equates to better perceived details and the ability for the K9 to get you that much closer to what the sound engineer had in mind when laying down the tracks for your favorites.

Its superb dynamic range with a reference level of balancing is something more reserved for higher end sources including Fiios own K9 Pro models. But in the K9 you get a whole heaping loving of what makes your tracks sound so good in the K9. IEM listening is an absolute treat as this extreme low noise floor translates perfectly with IEM listening, not to mention via speakers or your favorite CANs. It is not perfect for the most sensitive IEMS but the K9s dynamic sound qualities are superbly relayed when your music plays. I have no issue with any of my IEMs including very sensitive ones in low gain. It is on the higher gains when I start to hear the noise floor creep up on my Solaris or AndromedaS. But these are the outliers, most of my IEM collection does just fine. It's reference level of balancing, its rich textured layering which equates to a more holographic imaging stemming from that superb black background heard via my best IEMS and I can’t even tell you just how much music enjoyment is to be had from the K9.

The sound quality shows a pristine sense of clarity with superb dimensional imaging finished off by a richer denser tonal quality, a large spacious sound presentation with power behind its sound. What you're getting is a higher level of sound quality for the price. Let me put it this way, I don’t have a comparable product anywhere close to how the K9 performs in sheer sound quality and its power at the price point. There is not a DAC dongle that can match its driving power, there is nothing close DAP wise that has its fully balanced architecture with its full dynamic range with a rich tonal character. If so I will gladly go buy it. Nothing that I have heard that has its superior layering and articulation. It is when you hear Fiios own M15S in DSD mode in Ultra power desktop mode is when the sonics reaches a similar level. That player cost more than the K9 Pro ESS is my point. If sound quality and ample power matters to you. You have to take the K9 very seriously.

So how does it sound vs the K9 PRO ESS?
The only way you can hear the actual differences is if you do what I am doing. Have them stacked on top of each other going from the K9 to the K9 pro ESS back and forth. It is crazy to me what Fiio is giving the consumer for almost half the cost of its own flagship. The SQ is in my estimation about 92% of what the K9 PRO ESS is. 92%! This makes the K9 clearly a better value over the K9 PRO ESS.

And if you're wondering how the new K9 compares to the K7 to justify a purchase at over 2X the cost of the K7. You can imagine with the sound performance being closer to the K9 Pro ESS. We are talking about a more refined sound and power vs the K7. A wider stage with better instrument separation, more articulate treble, a tighter cleaner, a more vivid sound with a blacker background. Going back and forth from the K7 to the K9. The K7s slight warmth and smoothness to its tuning has to do with the dual AK4493SEQ implementation and its ample bass end. K7 for the money is still to this day something astonishing and I really don't know too many sources at that price that can top the K7 for sound quality. The K9 will give you a definitive upgrade on the sound quality. This however, will depend on what your sound references are, and your use case scenarios, as some might like its full bass slightly smoother, more intimate sound presentation of the K7.

Listening to the K9 simply sounds more refined, It's more than just having more power on tap, music has a greater sense of scale overall on the K9. The K7 with Fiios own dedicated low noise power supply the PL50 might get it to be closer to the K9. What's nice about listening to the K7 is that it's got its own sound quality that is a bit different vs the K9 and the K9 ESS. Again more due to the AKM DAC implementation. However once you hear the K9 you will understand why I consider it a definite upgrade from the K7. It's got a much more substantial premium build, built in linear power supply and all the upgraded components of the K9 in comparison.

The value is stunning if you can understand what I am typing here. I will argue that the K7 for its price punches above its price for performance. The K7 has a dynamic full bodied sound quality with a full bass end that folks will gravitate to. For media and gaming the K7 easily hangs with its bigger brothers, but for music with more power? That's where the differences are. The K9 is simply more audiophile vs the K7 in comparison. Better articulation, richer tonal character, a tighter better defined bass, better layering, more dimensional, volume per volume a blacker background. It's a more grown up sound in comparison.

You are getting what is essentially a flagship level sound quality in the middle child of the Fiio DAC/AMP line up. There, I said it. This brings a new value leader for sound performance to the K9 over the K7 in my opinion as good as the K7 is. You get a more refined sound quality in the K9. An upgrade in the noise floor department which helps with that sound articulation and dynamism. A more detailed, better balanced sound, a wider more spacious presentation, better precision and imaging in the process. K7s dynamics are excellent for its price point and that is what makes its sound so intriguing. It does have a slight edge in warmth overall, a bit smoother in its sound presentation over the K9 and K9 pros. The K7 can sound just as good as any of its older brothers in comparison with the right IEM or CAN combination but sound quality overall clearly gets an upgrade in the K9. Knowing what I know now about the new K9 and how it performs vs the K9 Pro ESS, heck if the K9 was around when I was going all in on the K9 PRO ESS. I would have bought the K9 instead. It is that close.

To be fair, I still consider the K9 PRO ESS my absolute best sounding source I own. That extra 8-10% in sound quality for me is worth it. Laws of diminishing returns start with the K7, but you get something that is so close to Fiios own flagship product for so much less in the K9. It was actually head scratching for me when I did this comparison. Why did Fiio bring out a product so close to their flagship in the K9 Pro ESS? This is not a case of if the SQ of the K9 PRO ESS not being somehow competitive or just average for its price. I own sources that cost over double that of the K9 PRO ESS. It is the K9 PRO ESS I consider the best out of my collection of sources for sound quality. Is it more about Fiio bringing out a clear value statement in the K9, a cheaper version of their flagship that comes strikingly close? Maybe that is why they call it the K9 without the pro. The PRO gets you that 8-10% SQ and power uptick. The leap from the K7 is clearly evident. The leap from the K9 to the K9 PRO ESS, not so much.

In the end
This could be the result of Fiio just getting better with what they are doing with these ESS chips. Due to the AKM factory burn, Fiio much like the rest of the industry had to move on to different DAC chips. Fiio adopted ESS chips as a natural replacement for the AKM chips they have been using. In doing so they have gotten good at tuning the ESS chip, very good. I have noticed Fiio always advancing and getting better with each new iteration of a product and it could be just that they have managed to get the absolute best out of using the two ES9068AS in the K9. With the amplification, its clean power circuits, flagship build, connectivity and functionality all remain very similar to the K9 PRO ESS. The sound quality comes strikingly close.

This is Fiio coming out with a better product for less money. Better value as Fiio always learns a thing or two from prior DAC/AMPs and brings their know-how to the masses at a more affordable cost. It will be the enthusiast that will benefit. Just know if you upgrade from the K9 to the K9 pro, you’re not going to get a clear upgrade like you will get when you go from the K7 to the K9. The K9 Pro ESS is an upgrade in a few ways but I could think of so many other aspects to your sound chain you can spend that extra $350 you will save by getting the K9 instead. Get yourself a new Fiio FT3 open can to go with your brand new K9 to truly enjoy your K9 sound quality with is my point.

The build, the functionality, its power and most of all its sound quality has to be one of the absolute best at its price point and class. The K9 delivers on so many fronts for its intended use if you're in the market for a substantial upgrade in a desktop level DAC/AMP the K9 is a substantial product and works extremely well with all types of IEMs, CANs and active speakers.

If you didn’t get the message from reading my review and already own the K9 PRO ESS. No worries you have Fiios best sounding product. Be a proud owner to have one of Fiios absolute best efforts. The K9 however is now the new value king for desktop applications.

A message to my fellow IEM enthusiasts. You gotta try the K9 with your IEMS. You can thank me later. Thanks for taking the time to read and happy listening always.