FiiO K3 vs. K5 Pro vs. K7 vs. K9 Pro

1.5K

Don't forget to share if you found it helpful!

Greetings mate and Welcome aboard!

Stuart Charles here, HomeStudioBasics.com helping YOU make sound decisions leading to a beautiful audio experience that will make you fall in love with music (NOT gear) all over again, so…

This article, similar to my HIFIMAN, Sennheiser, and AKG writeups, will house any and all current, as well as future iterations of the products in question. 

Today’s column will highlight FiiO’s K series lineup, covering current DACS K3, K5 Pro, K7, and K9 Pro.

• Playlist >Here!<

We’ll discuss everything from sound to features, power output, and more.

By the end of this article,

you’ll know which is best for your specific needs.

To keep things simple and concise, I’ll rank them in order of value (worst to best) but it’s not exactly black and white which you’ll soon find out later.

Keep in mind that I have logged dozens (perhaps even hundreds) of hours on these and my goal for this is to help you purchase the right one specific to your own unique situation.

So let’s dive in!

#4

FiiO K3

Price: Check on Amazon! | Check B&H! | Official Review: Here!

In The Box

FiiO K3 Compact Headphone Amplifier and USB Type-C DAC (Black)

USB Type-C Cable

4 x Spare Foot Pads (Note: The 2 pads you don’t see are on the bottom of the unit)

Quick Start Guide

Limited 1-Year Warranty

Specs

• Capability: Up to 32-bit/384kHz.
• Stereo Crosstalk: ≥70 dB (1 kHz).
  
• Outputs: 1x Coaxial, Line, 1x 3.5mm headphone jack, 1x 2.5mm balanced
• DSD Support: Yes, 64/128/256.
• Output Impedance: 1.04. What is Output Impedance?
• Output Power (Single Ended): 220 mW @ 16 Ohms, 120 mW @ 32 Ohms.
• Output Power (Balanced): 320 mW @ 16 Ohms, 200 mW @ 32 Ohms.
• Output Voltage: 7.39 Vp-p.
• Digital Outputs: Coaxial: RCA for 192 kHz, Support DSD64 DOP
  Optical Out: Up to 96 kHz.
• Inputs: 1x Type-C USB.
• Signal-to-Noise Ratio: ≥113 dB.
• THD: ≤0.004%.
• Frequency Response: 20Hz to 80kHz.
• Op amp: 2 x OPA926.
• Low-pass filter: TI OPA1612.
• USB chip: XMOS XUF208.
• Dimensions: 2.8 x 2.3 x 0.9″ / 70.0 x 58.0 x 22.0 mm.
• Weight: 83 grams.
• Warranty: 1 year.
• Power: Bus-powered, 5 VDC 500 mA.
• Features: Bass boost, Gain switch.

FiiO’s K3 is certainly a useful product. 

In fact, I actually still use it with my Presonus Eris e3.5s.

Its 3.5mm output on the back is mega sweet and really comes in handy when you need something quick and dirty to connect something.

In this way, it acts as a preamp, but it’s also an amp/DAC combo.

The problem is that it doesn’t have a lot of power unbalanced, thus why I relegate it to preamp duties most of the time.

The good news is that you can run it balanced with a 2.5mm cable, so that’s nice.

It sounds excellent with a Sennheiser HD58X balanced for example.

It also supports DSD and generally provides your headphones with a crisp, neutral sound profile.

Front Panel

On the front are your volume pot, balanced jack, unbalanced jack, bass boost, and gain switch.

I hardly ever use the bass boost feature, but your mileage may vary.

Back Panel

The back contains the aforementioned 3.5mm out, as well as the Type-C jack that you’ll use to connect to a PC/Laptop, a Coaxial output, and an Optical output.

With optical or coax out, you can hook it up to something like a receiver or speakers that have optical in or coax in.

A good example would be something like the Edifier R1280DB Powered Bluetooth Speakers which have both an optical input and a coaxial input.

Build

The K3 is a fairly light unit but doesn’t feel cheap, with a rounded contour shape and elegant aesthetic that improved on the somewhat boxy/industrial-looking profile of the older E10K.

All in all, the K3 is still a great unit but you may not really need it nowadays.

In other words,

there’s something better.

#3

FiiO K5 Pro

Price: Check Amazon! | Check B&H! | Check Apos Audio! | Official Review: Here!

In The Box

FiiO K5 Pro

15V DC Power Adapter &

USB Type-B Cable

1/4″ Adapter

Extra Rubber Feet

Quick Start Guide

Warranty Card

Specifications

• Capability: Up to 32-bit/768kHz.
• Stereo Crosstalk: ≥75 dB at 1 kHz.
• Outputs: Stereo RCA, 1/4″ / 6.35 mm Headphone.
• DSD Support: Yes, DSD512.
• Output Impedance: 1.2 Ohm.
• Output Power: 1.5W @ 32 Ohm.
• Inputs: 1x Type-B USB.
• Signal-to-Noise Ratio: ≥115 dB (A-Weighted).
• THD: ≤0.004%.
• Frequency Response: 20Hz to 80kHz.
• Op amp: LPF Op Amp: Texas Instruments OPA1642, Driver Op Amp: Texas Instruments TPA6120
• Dimensions: 4.7 x 5.1 x 2.2″ / 12.1 x 13.0 x 5.5 cm
• Weight: 436g.
• Warranty: 1 year.
• Power: 15VDC, 1.5A
• Gain Switch: 0, 6, 12dB

I’ve recommended the K5 Pro for many years now as a great affordable entry-level unit that comes packed with features and won’t break the bank.

I still feel that way.

This is a fantastic unit with plenty of power and versatility.

Let’s take a look at all the ways you can use it:

Setup #1

USB into your PC

This is going to be the most common setup you’ll be using roughly 90.19574839% of the time.

Yeah, I aced math. WHAT OF IT?

Just plug one end into the back and the other end into a USB slot on your PC.

Now plug the supplied power jack into a wall outlet.

Turn the volume knob on.

From here,

you’ll likely see a red halo light which either means you’re on the wrong input, or you haven’t adjusted the audio settings on your PC.

If it happens to be on the correct input, the blue light will appear.

If the unit is recognized (and it will be), you’ll see “FiiO Q Series” as the name of the K5 Pro. Select that.

The halo light will remain red, but don’t panic just yet.

Tick the leftmost switch all the way down to the bottom position where it says “1 – U” (indicating USB).

Now go into your music App of choice and press play on a track. The light should turn blue.

In addition to blue, we’ve also got Yellow indicating anything above 48kHz, and Green representing DSD (up to 512).

If you want to play files above 48kHz in Tidal, you can. You’ll just have to enable exclusive mode.

Exclusive Mode

1. Click on the 3 bars in the upper left corner inside Tidal.
2. File > Settings > Streaming.
3. Scroll down to where it says “Sound” and “Sound Output”.
4. Click (More settings) to the right.
5. Now just tick the button to exclusive mode and the formats will change according to the file.

Now the Halo light will turn yellow for any master files inside the program.

DSD is a bit of a different story.

• Read: What Is DSD In Audio? Is It Worth Pursuing?

Most DSD files you’ll have to pay for, but there is a free library of songs that I used for the purposes of testing and comparing.

Unfortunately, I cannot remember what the website was, but you’ll see in the image below that I did in fact in fact test them out.

Setup #2

Line Out

The FiiO K5 Pro also acts as a preamp, meaning you can hook it up to separate unbalanced speakers!

Pretty neat. Just snag a pair of RCA to RCA cables and make sure to use the RCA output.

Then get a pair of Presonus Eris E3.5s (as an example), and plug the other ends into the inputs on the speaker. You will need some speaker wire to go from the left to the right speaker, but it’s pretty straightforward and Presonus supplies some in the package.

Once you’re all set, keep the switch on USB and turn the volume up on your speakers. You can also listen with headphones as well.

For that, just turn down the volume on the speakers.

Keep in mind:

This is not a balanced setup.

For that, you’d look at something like an Audio Interface and some JBL LSR305s, or use the K9 Pro balanced with the e3.5s.

Another option you have is to use the K5 Pro as just a DAC into a separate amplifier if you like to experiment with different setups.

You’re likely not going to do this right away, but it’s always a neat feature to have.

Just connect the RCA outputs to a separate amp that supports either line in (3.5mm) or RCA in.

Most amplifiers have a combination of one or both. An example would be JDS Labs’ ATOM, which has both.

• Related: JDS Labs ATOM Amp Review

Note: The line feature on the front acts as the line in.

Speaking of,

Setup #3

Line In

The line-in feature on the K5 Pro is also very useful in that you can use it as just an amp from a separate DAC.

Are you beginning to see the possibilities?

Any DAC that has, you guessed it, a line out or RCA outs will work here, and again, all of them either have one or both.

An example would be something like JDS’ ATOM DAC.

With Your Turntable

But wait, THERE’S MORE.

One of my favorite past times is spinning vinyl.

The K5 Pro has you covered here as well, but it’s even simpler than you think.

Just use the RCA cables from your turntable and plug them into the K5 Pro’s RCA inputs.

Flip the switch up to “line” (middle) and voila, you’re listening to John Coltrane’s Love Supreme (or whatever record you want).

You can also listen to the Eris’ mentioned earlier in this turntable setup.

Simply run RCA to line (or RCA to RCA) from the outputs of the K5 Pro to the speakers, keep the switch on line and unplug your headphones.

To further illustrate this point,

the K5 Pro doesn’t have to be plugged in via USB with this method since the signal is coming from the turntable and is only amplified by the K5 Pro.

You also don’t have to have your turntable plugged in via USB either since, again, the signal is being powered by the K5.

You will obviously still need the turntable connected to wall power.

Setup #4

Coax from your TV or Receiver

This is one I personally haven’t tested yet, but the concept is simple.

If your TV has a coaxial output (and most do), simply plug the other end into the coaxial input on the K5 Pro and then flick the switch up to “3 – S” (indicating S/PDIF).

If you have something like a CD Player hooked up to your receiver, you can then output the sound from the receiver via coax into the K5 Pro and listen to your CDs that way.

Setup #5

Optical In from a console

This is perhaps my favorite method, as the PS4 is my main centralized hub for everything I watch or play.

I can watch movies, stream Netflix, YouTube, etc., as well as play some games.

The setup is simple.

Just run an optical cable from the back of your PS4’s optical out into the input on the K5 Pro, also making sure the K5 Pro is connected to wall power.

Now you’re READY.

Check out this graphic I did of all the different things you can do with it:

OK, that’s all well and good, but what about the K7?

#2

FiiO K7

Price: Check Amazon! | Check Apos! | Official Review: Coming Soon!

In The Box

Specifications

• DAC: AK4493SEQ*2
• Decoder: XMOS XUF 208
• Amplifier: Dual THX AAA 788+
• Outputs: 6.35mm/4.4mm
• Inputs: USB/TOP/COAX/RCA
• Output Power 1: ≥2000mW (32Ω, balanced/THD+N < 1%)
• Output Power 2: ≥1220mW (32Ω, single-ended/THD+N <1%)
• Output Power @ 300 Ohm: 560mW
• Signal-to-noise ratio: ≥120dB (A-weighted, UAC)
• Noise Floor: PO<4.4μV (A-weighted, UAC); BAL < 7.7μV (A-Weighted, UAC)
• Output Impedance: <1Ω (32Ω load)
• Weight: 610g
• Dimensions: About 120mm x168mmx55mm
• Materials: Aluminum Alloy, CNC finish

I just received the K7 in the mail and for all intents and purposes, the K5 Pro and K7 are almost exactly identical in build, sound, and features.

So everything I just said above with regards to the K5 Pro?

Apply it to the K7.

With that, do keep in mind a few notable differences between the K5 Pro and K7:

• The K7 is slightly larger length-wise.
• The K7 has the THX stamp. Related: What is THX AAA Technology In Audio & Video?
• The K7 has a balanced 4.4mm jack.
• The K7 lights up in a rainbow of colors upon initial startup (Turn the knob).
• The K7 is a bit heavier at 610g vs. 436 for the K5 Pro. Keep in mind they feel around the same in your hand.
• The K7 displays teal instead of blue for all files below 48kHz.

In addition to all of that,

the interface is slightly different this time around, and arguably more convenient/easy to see.

Instead of your input being a switch, there’s a button on the leftmost side that cycles between USB, Optical, Coaxial, and Line.

Above that, you’ll see 4 LED lights that coordinate accordingly. The rainbow-colored halo around the Volume pot that displays on startup also appears when pressing the input button and cycling between sources.

The color thing is inconsequential, but you will likely appreciate the LED lights in the upper left as it’s much easier to see which input you’re on.

In other words, it’s a lot more intuitive than the K5 Pro.

As far as the output section goes, it’s a simple switch that cycles between LO, PRE, and PO.

1. LO – This will be used with your balanced 4.4mm headphones/wiring.
2. PRE – This is the preamp section and will be used to connect to separate active speakers like the Presonus Eris e3.5s.
3. PO – This will be used with your unbalanced (single-ended) headphones/wiring.

Sound & Power Output

All of that is fine and dandy, but if there’s one issue I have with the K7, it’s this:

It seems to have way less power unbalanced than the K5 Pro.

This is something I’ve been noticing with FiiO since they came out with the K3, and it’s fairly irritating.

For instance, I was shocked to find that with my K702 on low gain, I have to turn the dial all the way to roughly 2-3 o’clock.

With the K5 Pro on middle gain, I’m only at 11, and low gain I’m at roughly 12.

I don’t know if FiiO is expecting most people to be using balanced nowadays, and I suppose that’s fair.

This could simply be a matter of how they design their volume potentiometers nowadays. 

For instance,

The K9 pro’s volume knob also took quite a bit of turning to reach an acceptable level.

From FiiO’s website:

“Thanks to ADC curve reconstruction, experience a smooth 112 steps of adjustable volume free of channel imbalances and noise – ensuring that every note is faithfully reproduced.”

Aside from some clear market-speak, this seems legitimate when you consider that it matches up with my experience.

There’s virtually no imbalance at lower volumes and it’s a rather smooth turn from quiet to louder.

Still,

many people are going to be a bit disappointed in having to pump that dial, and in all honesty, I was a bit taken aback by it as well.

For instance, this reviewer on Amazon described it as a “laggy volume control” and I’m assuming he means the same kind of thing I’m pointing out.

It simply feels like you’re doing a lot of turning even though on paper the unit technically has more power than the K5 Pro.

It’s important to remember that I’m kind of nitpicking a little as you’ve still got high gain + the balanced feature which kind of mitigates the issue to an extent.

Sound-wise, there are almost no differences between the K7 and K5 Pro, and if they’re there, it’s incredibly subtle.

The K7 advertises less than 1 Output Impedance and IIRC, the K5 Pro’s is around 1.2. Again, not a whole lot of discrepancy there.

This is a smooth, crisp backdrop that works very well with all of your music, so don’t worry too much about “how it sounds.”

In any event,

let’s take a look at the K9 Pro before we wrap this up.

#1

FiiO K9 Pro

Price: Check Amazon! | Check Apos! | Check B&H! | Official Review: Here!

In The Box

FiiO K9 Pro Amp/DAC

USB Type-A to Type-B Cable

Power Cable

Bluetooth Antenna

1/4″ Headphone Adapter

Quick Start Guide

Warranty Card

Specifications

• Form Factor: Table Top
• Converter Type: D/A
• Number of Channels: 2
• Conversion Formats: S/PDIF (Coaxial), S/PDIF (Optical), TOSLINK
• Converter Circuitry: A/D Chipset:
  1 x AKM AK4499
  1 x XMOS XUF208
• Display: None
• Max Sample Rate/Resolution: 384kHz / 32-Bit (DSD256)

Analog Audio I/O

• 2 x RCA Coaxial Unbalanced Line Input
• 1 x 4.4 mm TRS Balanced Line Input
• 2 x XLR 3-Pin Balanced Line Output
• 1 x 1/4″ TRS Unbalanced Headphone Output (Front Panel)
• 1 x XLR 4-Pin Balanced Headphone Output (Front Panel)
• 1 x 4.4 mm TRS Balanced Headphone Output (Front Panel)

Digital Audio I/O

• 1 x RCA Coaxial S/PDIF Input
• 1 x TOSLINK Optical S/PDIF Input

Other

• Host Connection / USB: 1 x USB Type-B
• USB (Non-Host): 1 x USB Type-C
• Wireless Connectivity: Bluetooth (Audio Streaming, Mobile App)

Performance

• Frequency Response: 20 Hz to 20 kHz

Max Output Level

• XLR Line Outputs:
  +5 Vrms
• RCA Line Outputs:
  +2.5 Vrms
• 1/4″ Headphone Outputs:
  +26 V p-p
• 4.4 mm Balanced Headphone Outputs:
  +51 V p-p
• XLR Balanced Headphone Outputs:
  +51 V p-p

Headphone Output Power & Output Impedance

• 1/4″: 1.1 W into 16 Ohms
• 1/4″: 2 W into 32 Ohms
• 1/4″: 278 mW into 300 Ohms
• XLR 4-Pin: 1.1 W into 16 Ohms
• XLR 4-Pin: 2 W into 32 Ohms
• XLR 4-Pin: 278 mW into 300 Ohms
• 4.4 mm: 1.1 W into 16 Ohms
• 4.4 mm: 2 W into 32 Ohms
• 4.4 mm: 1.1 W into 300 Ohms
• Output Impedance: < 1 Ohms (32-Ohm Load)

SNR

• RCA Line Outputs:
  ≥ 123 dB (A-Weighted)
• XLR Line Outputs:
  ≥ 128 dB (A-Weighted)
• 1/4″ Headphone Outputs:
  ≥ 123 dB (A-Weighted)
• XLR Balanced Headphone Outputs:
  ≥ 123 dB (A-Weighted)
• 4.4 mm Balanced Headphone Outputs:
  ≥ 123 dB (A-Weighted)

THD+N

• RCA Line Outputs:
  < 0.0007%
  XLR Line Outputs:
  < 0.0004%
  1/4″ Headphone Outputs:
  0.0005%
  XLR Balanced Headphone Outputs:
  < 0.0004%
  4.4 mm Balanced Headphone Outputs:
  < 0.0004%

Crosstalk

• RCA Analog/Line Outputs:
  ≥ 110 dB (1 kHz, 10 kHz)
• XLR Analog/Line:
  ≥ 123 dB (1 kHz, 10 kHz)
• 1/4″ Analog/Headphone Outputs:
  ≥ 75 dB (1 kHz, 32-Ohm Load)
• XLR Analog/Balanced Headphone Outputs:
  ≥ 114 dB (1 kHz)
• 4.4 mm Analog/Balanced Headphone Outputs:
  ≥ 114 dB (1 kHz)

Digital Audio

Sample Rates

• TOSLINK Optical S/PDIF Inputs:
  Up to 96 kHz
• Coaxial S/PDIF Inputs:
  Up to 192 kHz
• USB Inputs:
  Up to 384 kHz (DSD)
• Bit Depth: Up to 32-bit
• Digital Audio Decoding: DSD

Power

• Power Requirements: AC Input
• AC Input Power: 110 to 230 VAC, 50/60 Hz

Physical

• Dimensions: 8.9 x 7.9 x 3″ / 22.5 x 20 x 7.6 cm
• Weight: 6.2 lb / 2.8 kg

Packaging Info

• Package Weight: 9.465 lbs.
• Box Dimensions (LxWxH): 14.1 x 13 x 6.2″

Now some people may say:

“Oh, you’re just recommending the K9 Pro as the best overall value because it’s more expensive.”

Well, no, not really. I’m just ranking them in terms of value as I see it.

The difference between you buying a K9 Pro vs. a K7 or something, commission-wise, is around $25. Hardly enough for me to go shilling lol.

In other words,

I have little incentive to convince you to buy the more expensive product.

It’s inconsequential.

In fact, you could get a K7 or K5 Pro and be perfectly satisfied for years, and which of those you go with depends on if you plan to primarily run balanced over single-ended.

The K9 Pro is a better value because it has the following:

1. Bluetooth
2. The FiiO control app feature
3. An extra headphone input (XLR)
4. Balanced XLR outputs (for use with professional studio monitors that utilize TRS or XLR inputs)
5. A 4.4mm input
6. A coaxial input

The K5/K7 have none of these things.

Now, are those things worth roughly $500 extra?

Probably not, but again, it depends entirely on you and what you’re willing to spend.

Aside from those aspects, yeah, it’s about the same thing as a K7 or K5 Pro.

I will say that the K9 ESS Version (vs. AKM) does have a cleaner, and more sterile presentation (it also tends to sound more open and airy), and that’s something I’ve discussed at length and stood behind for a few years now.

Still, I wouldn’t say the sound of the K9 overall is any “better” (whatever that means) and there are many people who don’t need the extras I just mentioned.

Remember, I always recommend based on value and I believe it to be the best-valued desktop amp/DAC there is right now.

That said,

if you don’t need those extra features, don’t buy it.

Buy a K5 Pro or K7 as you’ll be happy as a clam. You can thank me later.

In the meantime, let’s watch a couple of videos before we wrap this up and give a final verdict.

Video Discussion (AKM Version)

Don’t forget to leave me some love and subscribe! <3

ESS Video

Here’s the updated ESS version!

Final Verdict

I think we can safely discard the K3 at this point.

While useful, it’s not really necessary in 2023 and beyond.

If you’re not planning to use balanced headphones, go with the K5 Pro which is still an amazing value.

If you’re planning to use balanced headphones A LOT, go with the K7 and save some money. It’s another great FiiO product in a long line of many and I wholeheartedly recommend it as a fantastic all-in-one desktop solution.

Learn More:

 

If you think you’ll need the features of the K9 Pro, by all means, buy it.

It’s a great desktop Amp/DAC and can basically hook up to anything.

Learn More:

 

Well, that’s about it for today my friend! I hope you’ve enjoyed this FiiO K3  vs. K5 Pro vs. K7 vs. K9 Pro Comparison and came away with some valuable insight.

Questions? Comments? Requests? Did I miss the mark on something? Please let me know down below or Contact me!!

If you love what I do here and want to support the blog and channel in a more personal way, check me out on Patreon and discover all the value I have to offer you.

Just want to make a one-time donation? Click here. Your support is greatly appreciated and helps keep this site running!

Which of these fits your needs best? I would love to hear from you. Until next time…

All the best and God bless,

 

 

-Stu

[Xtr@Ba$eHitZ]

Can’t decide which headphones to purchase? Interested in a complete buyers guide outlining over 40 of the best options on the market? Click on over to the best audiophile headphones to learn more!!

Be sure to also check out my Reviews and Resources page for more helpful and informative articles!

Don't forget to share if you found it helpful!