HiBy FC4 Headphone Amplifier Portable DAC with 4.4mm and 3.5mm Headphones Outputs Support MQA16X PCM768K DSD256 High Driving Power for Android/iOS/Mac/Windows

The HiBy FC4 Headphone Amplifier has some impressive features. This amp delivers great sound quality, significantly better than my old model. It's lightweight and doesn’t need an external power source—just plug it into your device. The sound is clear and distortion-free, enhancing the performance of various headphones.However, there are a few drawbacks. While it works well with my phone and laptop, it drains the battery quite fast, especially on an iPhone. Some users might find the sound a bit too technical and would prefer something warmer. Also, it may not adequately drive more demanding headphones. Overall, it’s a solid choice for those looking for an affordable, portable DAC, but it’s not without its limitations.

Excellent! Easy plug-and-play usage. Noticeable improvement in sound quality when playing higher quality content (Tidal MQA, not so much when playing youtube). The sound improvement to my ears is specifically in the separation of instruments and in the highs. It is not strong enough to push demanding headphones such as sennheiser 660 or any hifiman, so know what you are buying. I am using mine with shure and I am very happy with the result.

The FC4 is a solid budget Dongle DAC that does exactly what most people want, quality plug and play HiRes sound with no frills or gimmicks.The aluminum construction of the housing is very durable, and both the 3.5mm and 4.4mm jacks engage with a comforting click. The volume rocker is fit snugly in the case, and provides positive feedback when pressed. There is a small LED at the top of the unit indicating power, and the bit rate of the content being played. Included accessories are a functional, yet mediocre quality, rubber sleeved USB 3.0 Type-C to Type-C cable, and that's about it. The DAC is a plug and play affair, and requires no software or utilities to work. Just make sure you select the higher UHD quality in your favorite streaming service, to get the most out of it.The tonality of the FC4 is neutral, leaning bright, with the Classic ESS filtering style giving things that little bit of extra sparkle and detail up top. The so called "ESS Sabre Glare" that gives a tinge of edginess to the treble response. Some brighter IEM users may what to be aware that the FC4 will potentially be a tab bit harsh or sibilant on some tracks because of its brighter nature. Especially when a compared to some of the the CS43131 based DACs out there, which might not have that extra spice up top.But this brighter tonality works great for more mellow or dark IEM's, like the Hidiz MP145, or the AFUL Explorer, or the Tangzu FuDu Verse1, where the FC4 will reward you with a little more detail and technicalities up top, where a more neutral or warm DAC might leave you wanting more.In terms of output quality, the 3.5mm and 4.4mm output sound indistinguishable. Obviously, the 4.4mm output pushes more power behind it, and some IEM's benefit from that, but out of all of my <$100 DACS with both 3.5mm and 4.4mm outputs, the FC4's 3.5mm output is second only to the iFi Go-Link MAX in terms of quality. And of course the 4.4mm is perfectly composed, and handles harder to drive sets, like Planars, with ease.Musicality is solid on the FC4, and it feels natural and full, and plays well with all genres thrown at it.When used with the appropriate Lightening OTG Cable, the FC4 also works very well with iOS Devices. And integrates nicely with the interface. It does however lose the independent volume control on the DAC itself. And it does control the iOS primary device volume control instead. Which may be problematic for some, but probably a welcomed feature to an iPhone or iPad users point of view.It is worth mentioning that this unit DOES need FIrmware Updates right out of the box. And I discovered that there is something about AMD Ryzen CPU's, and the way they handle USB, that the HiBy Flash Utility does NOT like. I had to fire up an older Intel based system to get it to work properly, and then the firmware upgrade happened without issue. I imagine it is related to the old x86 compiler used to create the firmware update software, but I digress.I also had one incident where I came back from my laptop after an extended 2 hour long meeting, where I had left this Dongle DAC connected with nothing playing in the background, and it was SUPER HOT! As in Hot Potato, to hot to hold, hot. I have no idea what happened or why, it has never done it again, or since. I thought that maybe it was an issue with the Planars I was using at the time (MP145), but i have used them since with no repeat issue??? Now, if I am stepping away from my phone or laptop or PC for more than 10-15 minutes, I am sure to unplug the FC4.The only other issue I have experienced is slightly higher than average power draw when compared to other similar basic Dongle DAC's, like the Fosi DS2, or Moondrop Dawn Pro. I dont know if this is down to Firmware Logic, or the DAC itself. But it is interesting that the FC4 seems to have a slightly higher battery drain. But it is not obnoxiously high as to be a nuisance. But it is something to at least be aware of.Overall, as long as you understand that this is a basic unit that does exactly what it says it does, and nothing more or less, then it will work perfect for 99% of the people out there looking for that. If you want more features and a control app, look elsewhere, this is a basic Dongle DAC with clean output, and great power handling, that is plug, play, and enjoy, without complications or needless fiddling. It would be an easy 5 star if not for the Firmware Update struggles.

This amp has superb sound quality. It replaced a rechargeable model that I had for years. This amp has great build quality and awesome performance. Distortion free sound and passes hi res audio. It’s a must have and works off the power of the device it’s connected to. You don’t need an external power source or need to charge it. This amp is perfect for the money. It’s also very light and compact.

Update: Returned it. 😱 I liked this unit a lot, as my original review indicated, until it started skipping and cutting out after about 2 weeks. I tried various IEMs and cables with the FC4 and had same problem with all. Meanwhile, the $9 Apple dongle works perfectly. Disappointing, but Hiby QA seems to be lacking.I really like this little DAC. The all aluminum form factor is simple and clean, with quality fit and finish. The sound is great - clear and neutral and there is plenty of of power to drive my IEMs. It’s also fairly light on the battery of my iPhone 15 Pro. I’ve had no connectivity issues at all on IOS; it just works, and works very well. I can’t say a single negative thing about it, and the price is modest to boot. I highly recommend it.

I used these everywhere and it sounds great with the in ear monitors.

Very nice DAC at price point. App works fine, but only tidel music is completely intergraded. I would buy again.

If you watched a review of this item on any YouTube channel or comparison, and you liked it, buy it with confidence as it's exactly as they told you. The sound is very technical, and personally, I would have liked it to be a bit warmer. As they say in the reviews, the highs are good, not overly pronounced, but I could live with less of that. The amplification power is great, it drives whatever headphones you put on it. In my case, a pair of Sennheiser HD600 without any problem, and it has more amplification capacity than necessary. While the reviews say it doesn't consume much battery, in my iPhone 13 Pro, with the battery at 100% and its health at 85%, music playback before the battery is fully drained lasts 2 hours, 2 and a half hours. Very little. That leads me to recommend that if you use an iPhone (where we all know that battery life is not its strong point), invest a little more and buy a dedicated DAC that doesn't need to be connected to a phone. That will be my case in the near future.