Opening the box, we find the device, a USB A to USB C cable (with a removable adapter to convert it to USB-C to USB-C), a 4pin 3.5mm female to dual 3.5mm TRS cable (to use a 4 pin headset with the two separate input/outputs on the device), an optical cable and a fairly decent user manual.

With the bad out of the way, here comes the good news! This DAC seems to excel with sensitive dynamic driver headphones. The differences between this unit and more expensive units become far more incremental.A unique feature of this amp is that it comes with a gain switch. This allows you to easily adjust the level of gain between low, medium, and high, depending on how much power you want to drive to your headphones. This will be a handy feature to have on your headphone amp if you want to better adjust the sound to your preferences. Mine was perched a little higher off my desk on the edge of my monitor stand base, so that was a non issue for me. Oh man, That Fosi Audio Q4 is not good. I almost never talk bad about products but this is the exception. You're better off running onboard audio by far. It's legitimately a downgrade from almost any onboard audio. Note:The Micro-USB cable cannot be fully inserted into the device power port; please do not force it. Subsequent revisions have been made. Unless, of course, you want to practice your español and read the Spanish version (link to blog at the end of this post).

Therefore, when Fosi reached out recently and asked if I would be interested in trying out and possibly reviewing any of their products, I said that I would be interested in giving the K5 Pro a whirl and seeing what they could offer in this budget priced category.Also, the minimum bass volume seems to introduce some artefacts, however at this greatly reduced volume, you likely wouldn’t hear any of those artefacts anyway. The K5 pro come in a good size box so I was surprised to see how small this gaming Amp was, look wise its very attractive gun metal finish with silver knobs. The device is well made and solid. it has more than adequate IO and the Bass and Treble is appreciated as I love physical EQ. The device was powerful to drive my planar headphones and gentle enough to run my IEMs so I am impressed with that already. The FX-Audio DAC-X6 Mini comes with a range of input and output options so that you can use it for a variety of purposes. It includes PC-USB, optical fiber, and coaxial three inputs. It can easily be connected to DCD, DVD, and TV set-top box. In terms of output, the headphone amp features RAC, 6.35mm headphone port 2, and it can also be connected to an active speaker, tube vacuum amp, and a power amplifier.

I do not own any products with optical or coaxial output, so that part will not be part of this review. Let’s talk about one last negative before moving to the positives, getting all the bad news out of the way at once. In the case of planar magnetic headphones, at least the ones I have on hand, the K5 Pro does struggle. It is to be expected as it is powered by USB and I doubt that there is much in the way of current going on, but as soon as things like the HE400se are pushed with some strong and fast bass, you can tell that this little amp is struggling to keep up. Does anyone know a solution to remove the static / hissing noise from Spotify? Any help is appreciated. Thanks The Fosi Audio Q4 headphone amp is another great choice if affordability is a factor for you. This headphone amp allows you to adjust the bass and treble to suit your preferred tastes. I replaced the 305's with Adam T5v's after Amir's review that I like very much but i am still in two minds as to whether they have the same wow factor as the JBL's. The 305's are really special, the Adam's are still very satisfying.

Those who know the SA3000 are aware that is is a detail and treble-monster with a rather weak bass response. Correcting those ‘flaws’ to my taste on the K5 Pro was so simple and brought my SA3000 to another level of enjoyment.

I noticed it especially failed to produce convincing dynamics with large planars, which are notoriously power-hungry, and with some more demanding dynamic headphones like my JVC HA-DX1000 it was not able to control sub-bass texture with authority. Q4 has been welcomed by the majority of users since its listing, buy the best gaming DAC on a limited budget and bring you HiFi enjoyment. Desktop: Topping MX3s, Topping DX5 Lite, Ino Audio piMx, SoundblasterX AE-5+, Dan Clark Aeon 2 closed, AKG 271 Studio (mostly for gaming)..CPU > Intel core i7 9700k, GPU > RTX 2070 8gb, RAM > Corsair Vengance 2x8gb 3000mhz, Motherboard > Z390 Gigabyte Aorus Pro Wifi, Storage > 1TB HDD & 2pcs of 500gb M2 SSDs, Cooling > H100I Corsair Platinum, PSU > Corsair RM750X V2