QuestyleM15i Headphone Amplifier [MFi Certified] Portable USB DAC Amps with 4.4mm and 3.5mm Dual Outputs Supports PCM 768kHz/DSD512 High Resolution Lossless for Smartphones/PC/Laptops

This thing sounds fantastic. I am using it with $900 Sure SE846 headphones. I haven't listened to any other dongle DACs so I don't have much for comparison, but compared to other audio equipment I've listened to over the years, this thing is precise and musical. It has a lively sound, playing FLACs from my iPhone via Doppler app. Just sitting and listening to music, doing nothing else, is very enjoyable now.The device seems to work best with Apple devices. I tried using it with my Windows desktop PC, but the sound was not nearly as good. I have no idea why. I won't bore you with a subjective description of the sound, just know it may be hit or miss with Windows. I haven't tried it with Linux yet. Fortunately I only need it for use with my Macbook Air and iPhone, but more compatibility is always good.The only improvement I could suggest to the manufacturer would be a small volume dial. From what I have heard while cruising the internet, software volume control causes a reduction of the sound quality. I have no idea if this is true, but supposing it is, it could be avoided with a volume dial. The sound and detail on this device is great so it may be beyond my ability to hear.If you're considering this device, just get it. I almost got a DAP instead of this DAC, but I'm glad I got this. While it does limit the compactness of the phone, I think it is better than fiddling with a crappy version of Android on one of the many DAPs out there. Until a new version of the iPod is released, I think this is the way to go. You probably have better battery on your phone with this plugged in than you would with many of the DAPs running Android anyway. I'm just a guy yapping, make your own choices. But know that this thing definitely has brought me happiness and I hope you enjoy it, too.

Good purchase, wish i would have bought it on sale though.

This dongle is great for my Hifiman Ananda headphones. Plenty of power. The DAC section sounds solid while not amaizing. For the price (got it for 180 USD) and size the performance is satisfactory. Would recommend.

This thing is absolutely great. It is great for a headphone amplifier or to just use a a usb DAC in car audio through an aux input. I have other DAC/amps that cost more, but this one is my new favorite!

Just like others 1 star reviews that this dongle have really serious performance problems and it won't start or the M15i may be freezing when switching from 4.4mm to 3.5mm. A forced unplug and replug to resets it, also3.5mm output does not wake the device, and it won’t turn on unless you unplug and replug from your phone. No wonder is frequently return items.

It's hard to give a 2 star review to great sounding DAC/Amp dongle. But, I've put so much work into this thing and what's the worst is that it broke my favorite phone of all times (The Nubia Z60 Ultra LE) because the cable connector is as stiff as a board which turns the USB plugs into pry bars and caused the port on my 700+ phone to be unusable. Hence the pictures of it attached to my new and far interior S25+. Not to mention it has a mind of it's own and the volume fluctuates depending when plug it in or in what order I plug it in. To get it to properly run at it's full preferential you need to use it with USB AUDIO PLAYER PRO. Which brings it's own suite of problems vis-à-vis calls and notifications. Because the app completely takes over the audio. But if you do decide to get it I recommend The SHANLING L3 cable or a xiwai 2 in 1 USB-C OTG converter male to male. There was a little space between my phone and the m15i so I use 3M double-sided tape to stick it to a cheap case and that's been my solution. But honestly, is recommend the iFi Go Link Max and to update the firmware on there website via a Windows computer. I messed up and they walked me through everything the man's name was Liam and he couldn't be more helpful. And honestly I think this thing sounds better it's got 130 DB dynamic range. Questyle is vague with their mw output but on all my ANDROID devices the volume has been almost the same IF the M15i is working at peak performance. Also the Onix Alpha Xi1 is supposed to really good too. It has the same components as my Fiio KA15 which definitely wins coolest looking nostalgic dongle but even with the higher rated power it's pretty much running over ear and IEMs at the same volume but doesn't sound quite as good as either of mine. Hope this helps