Fosi Audio HD3 Headphone Amplifier & DAC Portable Mini HiFi Stereo Amp 192kHz/24bit PCM Native DSD128 Type-C for iPhone, iPod, iPad and Computers (3.5mm Single-Ended & 2.5mm Balanced Outputs)

Bought this mainly for using with my pc/laptop as well as with my iPhone 12. On my PCs it works great as you would expect. However this is not compatible with the iPhone 12 at all. You can plug it in but the device does not detect the unit. However it does work on the latest generation iPad Air.

Honestly, I can't tell the difference from the headphone out on my phone with low impedance headphones. High impedance 'phones get louder, that's about it. Granted, I can't tell the difference between 320kHz MP3s and lossless, either.Battery life is on the order of 1-2 hours of listening time, and it can't charge and play at the same time. There's no auto-off with no input, so you're going to accidentally run the battery flat pretty often. It's cheap, and it does what it says on the box, but I can't say my listening experience has changed for the better.

This was a pleasant surprise, it’s definitely not a perfect product, but for the price it’s a fantastic addition to your audio stack. It powers my 6XX pretty well, works well with most devices. I don’t particularly like the fact that there aren’t two USB-C ports, but maybe that’s v2.

Most audiophile would like to use this with iPhone or iPad, however, the manufacturer omit the Apple lightning cable and trying to find a compatible usb C was not a pleasant experience. Sadly, I had to return the unit.

It sounds really good, especially for the price. It does have an odd rattle sometimes when it's shaken.

Solid build but sound improvement did not meet my expectations.

Pretty good for its size

I review audio gear on YouTube and have a lot of experience with portable amp/dacs. There's much to like about the Topping NX4, iFi Hip Dac, and Monolith THX Portable...but they are well above $100. My typical advice to new audiophiles is that they should not rush out and buy the most expensive gear they can afford. People should first figure out if they even want to get into this hobby, and how dedicated they want to be.To that end, I try to find affordable alternatives to the much more costly options. The Fosi HD3 is one of a few portable amp/dacs for around $100 that does bring value within its price category.This device has a fairly sturdy build. The only issue I had is that the HD3's buttons were a bit wobbly. I do not think they will pop out or break, but a bit more tension would have been preferred. The operation and use is otherwise simple and intuitive. The device is plug and play with Mac, Windows, Android, and iOS.The HD3's sound signature is neutral, as far as I can tell. I conducted a test using my Ollo Audio S4X, one of the most neutral headphones I've heard. The HD3 did not seem to color the sound. There was no hiss or noise or other faults.The HD3 also has plenty of power for most dynamic driver headphones. The HD3 was able to drive the HD6xx in single-ended output, though near max-volume. While connected through balanced, the 6xx got overwhelmingly loud. I also tried my 600 ohm Beyerdynamic T1 2nd Gen. The HD3 was able to provide sufficient power to get the T1 to comfortable volume through single ended. Over balanced, the T1 got to the limit of safe listening volume but at max on the HD3. Typical IEMs will have no issue whatsoever getting plenty of power.The HD3's ability to decode high resolution audio is also a huge plus. The ES9018 dac used here is capable of higher resolution than what the HD3 provides, but this should not be an issue of contention. The vast majority of audiophiles do not have anything higher than CD-quality music, and the HD3 covers that area quite well.Overall, the HD3 is a very good option for those on a budget. It doesn't have the bells and whistles of the more costly alternatives, but it doesn't need to. You're paying $70 for clean, clear, and neutral performance with plenty of power for the vast majority of headphones and IEMs.