Current testing methodology is v1.2
September 16, 2022
Fosi Audio K5 Pro
4.4 x 3.7 x 1.2 in
I love a good digital-to-analog converter (DAC).
It’s just something that you can put in your audio flow that can make moderately decent headphones sound good and good headphones sound great.
Fosi Audio has been in my sights for a long time now, and I’ve watched them grow as have the early days of SMSL Audio.
I used to own an SMSL Audio headphone amp years ago and I love that they, like Fosi Audio, have done a great job of surviving.
They’re not only surviving. They’re also continuing to improve their products, the build quality, and the functionality to something that is still affordable but well-tuned for really elevating your audio game.
Fosi Audio continues to target the budget audiophile and the budget gamer who’s looking for suitable hardware that’s durable and helps their gaming or listening experience.
They have a bunch of wireless units that make it great to connect Bluetooth devices to amps and speakers.
Fosi Audio K5 Pro Gaming Amp DAC
A great, tough little unit with decent output that can elevate budget headphones (and gaming headsets)
The Fosi Audio K5 is a decent little unit. It’s flexible in that you can connect Coaxial, Optical and USB-C inputs to it and easily switch between each input.
While I’m not normally interested in using Bass and Treble controls on Amps, these really help to improve the sound of even the most budget headphones.
Able to power up to 300 Ohm headphones, it did a great job on the OneOdio Monitor 80, which are 250 Ohms, and my DT 1990 Pro from Beyerdynamic.
The included microphone splitter allows you to connect your gaming headphones easily and isolates out mic from audio with ease.
While not as musical as some more expensive units, you have to keep the price in mind.
- Input Type: USB Type-C, Optical, Coaxial, Microphone
- Output Type: 3.5mm Headphone, RCA
- USB Sampling Rate: 24Bit/96kHz
- Optical/Coaxial Sampling Rate: 24Bit/192kHz
- Headphone Impedance: 16-300 (Ohm)
- RCA Output Level: 2V
- Power Supply: 5V
- Power Input Interface: USB Type-C
What’s in the Box?
- 1 x Fosi Audio K5
- 1 x USB Type-C cable
- 1 x Optical cable
- 1 x Headset Microphone Two-in-one Adapter cable
- 1 x User manual
Stuff I like
- Good power output
- Solid Build
- Not too large or heavy making it decent to travel with
- Easy to use and good LED feedback to understand what’s happening
- Bass and Treble controls a nice addition
- Elevated all the headphones (~7 pairs) I threw at it
- Great value for money
Stuff I like less
- Control pots are close so can be fiddly to change each
- Not a warm sound signature if that’s what your looking for
- Musical enough but not as musical as more expensive units
The BT20A amp is one of their best sellers, which is an awesome little two-channel stereo amp receiver that also has Bluetooth 5 connectivity, so you can connect this to some speakers, into a unit, and make some great Hi-Fi for your home.
So when Fosi Audio reached out and said, “Would you like to try the K5 Pro?” Of course, both my hands went up in the air and waved like I just didn’t care.
Quickly dispatched and quick to arrive, I cracked open the box and stared at it for a little while, realizing I didn’t quite have enough time to give them a good run.
I wanted to make sure that I tried both gaming headsets and headphones and gave them a good long listen so that this review was thoroughly undertaken and executed.
So, let’s have a quick look at the tech specs of the Fosi Audio K5 Pro Mini Stereo Gaming DAC. Then we’ll have a look at the sound quality and how they perform across different headphone types.
The K5 is a USB-C unit, but it also has optical audio, a coax, and an RCA out option. So far I’ve been feeding most audio in through the USB-C connectivity to my MacBook Pro.
With a unit this small and portable, it’s unlikely that I’m going to bother connecting it to any other device using the optical.
But it is a good option if your gaming devices offer it or the coaxial cable, which I still think is a little bit long in the tooth.
The sampling rate on the optical and coax is higher than the USB-C, but the USB-C alone has been pretty impressive.
The audio-out options are the RCA connections, which are something that I would probably use to play into my M-Audio studio speakers to elevate their audio performance. So that’s what you’ve got on the back.
On the front, you’ve got a 3.5-millimeter headphone input, a 3.5-mill mic input, and a three LED display lineup, which will indicate whether you are using USB, optical, or coaxial for your audio input.
This would allow you to have multiple devices connected. By simply depressing the volume knob, the button will switch between each of the channels.
Also on the front is a bass, a treble, and a volume controller. The volume controller not only switches channels and volume, but a press and long hold are what powers the unit off and on.
The build quality is pretty solid typical Fosi Audio stuff. It’s got a metal shell housing with some decent rubber feet for isolation and some strong Allen key bolts that hold it all together.
It feels tough. Even the knobs feel tough, and it feels like something that you could throw into your bag, take traveling with you, and you won’t need to worry too much about this getting knocked about.
I absolutely love that part of it. While I love my FiiO KA1 and how small it is, it is a little bit tricky and delicate, so I do have to make sure I pack it well when I travel with it.
With the Fosi Audio K5 Pro, of course, you have that added benefit of the mic input as well.
This is great for elevating your headphone listening experience by using just a headphone jack, and if you’re going to use it for gaming, you can use both the microphone and headphone jack.
In terms of compatibility, what’s cool about the K5 is that it is plug-and-play. There’s no stuffing around with bloatware or drivers, and it works directly with PCs, Macs, PS5, PS4, PS4 Pro, Nintendo Switch, and smartphones that are USB-C.
What’s in the Box?
In the box, you get the Fosi Audio K5 Pro unit itself with a USB-C cable, which goes to a USB-A plug adapter, which is also on top of a USB-C plug. So you can go USB-C to USB-C or USB-C to USB-A.
I love these cables that more and more companies are coming out with. There’s that little adapter on the end which is connected, so you can take that off if you want to do USB-C or you can use the USB-A adapter as needed.
It also comes with an optical cable. I was impressed with the fact that they would throw this in as well.
The final piece of hardware that comes in the box is a headphone-mic splitter. You can use this on your existing gaming headset.
If you have something like the Turtle Beach Recon 70p, you can plug it straight into the 3.5-mill jack and it will split out the mic and headphone channels.
This means you can plug that straight into the front of the two 3.5-mill inputs on the Fosi Audio K5 Pro and your gaming setup is ready to go.
How Does it Sound?
Well, I was quite late to do this review because I was having too much fun trying out a lot of different headphones with it. The Fosi Audio K5 Pro is the perfect pairing for any budget set of headphones you might have.
It elevates them to an impressive listening experience.
Compared with coming straight out of my MacBook Pro, my iPhone, or even through my FiiO A3 headphone amp, this thing is quite impressive in its ability to add clarity and elevate the overall listening experience on moderate headphones.
Some of the budget headphones that I tried on this, which I think a lot of people might have around this price point, were:
- FIFINE H8 headphones
- OneOdio Monitor 60 studio headphones
- SuperEQ S1 headphones
- OneOdio Monitor 80 headphones
- Turtle Beach Recon 70p gaming headset.
Every single one of these headphones sounded at least 40% better through the Fosi Audio K5 Pro. The headphones that I spent most of the time with, because they were just so much more pleasant to listen on, were the OneOdio Monitor 80s, which are 250-ohm headphones.
They sounded bright, elevated, and full, and were just so pleasant to listen to with the Fosi Audio K5.
I found myself skipping from track to track and smiling at each one, starting with “Animals” by Architects, which was a pretty banging tune.
“Move A Mountain” the stripped-back version by Dan Lancaster was just acoustic and bright and full of musicality. “Let You Down” by NF had good separation and a good bottom end.
“Hail To The Victor” by Thirty Seconds To Mars was just a solid rock track just banging away. “Mansion” by NF and Fleurie sounded spacious.
There’s a lot of reverb in that track and a lot of airiness, which just really came through on all the headphones I tried.
“Insubordinate” by Alt., which has an absolutely cranking introduction sounded super, and “Sword From The Stone” by Passenger, which is a great song, but can sound a little bit sleepy on the wrong set of headphones, sounded really musical and more than enjoyable.
The Fosi Audio K5 Pro’s ability to be fine-tuned using the bass and treble knobs at the front is really what makes them so flexible with whatever you are listening to through them.
Whereas I tend to typically run everything flat, with the Fosi and budget headphones together, the ability to tweak the bass and the treble either up or down at any point was the differentiator in making every single pair of headphones that I put to them sound better.
The overall power output of the unit was also impressive, with lower ohms headphones sounding significantly louder, and the OneOdio Monitor 80 250-ohm headphones being able to be driven at a very respectable level.
Having a little look at the tech specs, we can see that in addition to the USB-C, optical, and coaxial options, each has a slightly different sampling rate. Depending on the headphones, each one also has a different output power.
If you’re listening using the USB-C cable, the sampling rate is 24-bit up to 96 kilohertz. The optical and coaxial sampling rate is up to 24-bit, 192 kilohertz, which is a lot higher.
It supports anything from 16 to 300-ohm headphones. The next set of cans that I’m going to try out on these is my Beyerdynamic DT 1990 Pro and the Sennheiser HD 600s, which are also very high-impedance headphones.
The output power at 16 ohms is 1,000 milliwatts right up to 300 ohms, 80 milliwatts, which was more than enough to drive the OneOdio Monitor 80 to a point that was sonic, but not too loud.
I don’t really have any criticisms about the Fosi Audio K5 Pro Gaming DAC.
The knobs at the front are close together, so you do have to make sure that when you’re dialing one or the other up or down, you’re not interfering with one of the other knobs by accident. But I would rather have ports that are quite close together than have a larger unit that requires a lot more space on my desk.
The overall musicality of the unit is good, and they can make a good set of headphones sound great and a great set of headphones sound pretty awesome, but they are quite clinical in how they do that.
There is a steel note to them that is quite bright and hard-edged. It’s not a warm output.
It’s also not as dynamic or musical as some more expensive units, but that is an incredibly harsh and unfair criticism to make at this price point.
The Fosi Audio K5 Pro took all the budget headphones I lined against it to a point where I was more than happy to listen to them. The fact that I was late to do the review because I was having too much fun listening to them is praise enough for this little unit.
Given its price point, the plug-and-play feature, form factor, included accessories, and the fact that you can use this just as a headphone, amp, DAC, or as a gaming amp DAC puts the Fosi Audio K5 Pro at an easy four-and-a-half out of five stars for me.
And that only half-star is just because nothing is perfect, and I don’t think at this price you can expect it to be.
If you’ve got any questions, file them in the comments below. I look forward to getting into it. And thanks again to Fosi Audio for sending me the K5 Pro, which will now have a permanent spot on my desk next to my MacBook Pro setup.
Endless hours of experimentation, professional work, and personal investment in Home Theatre, Hi-Fi, Smart Home Automation and Headphones have come to this.
Former owner of Headphones Canada, a high-end headphone specialty retailer.
This post was last updated on 2023-09-28 / Some images from Amazon Product API & some links may be affiliate links which may earn us a commission from purchases.