M15i Mobile DAC Amp - MFi Certified Headphone Amplifier,ESS Flagship DAC, 3.5mm/4.4mm Balanced Output, Supports PCM 768kHz/DSD512 Portable USB C Audio Adapter for iPhone, Android, Laptop

I loved this dongle amp/dac. It has a very clean and neutral presentation and I've driven a 64 Audio U4s IEM, a closed-back Focal Stellia, and an open-back Focal Utopia with this little thing. No problem with any of these and it's particularly good from it's balanced 4.4mm output. I'd also like to note that Questyle's usb-c to Lightning cable (unfortunately it needs to be purchased seperately) is one of only two brands of "short" dongle cables that I have not had issue with (even the high-end cable can exhibit too much wiggle in the Lightning port, causing the dac/amp to disconnect). However, I did have a problem. The M15i died on the 6th day. It simply would not connect or power on. Note that it was not due to a bad cable; I tried several others and none worked. That said, I love this dac/amp so much that rather than return for a refund, I requested a replacement. I'm hoping I will be able to return with a positive update, but for now I have to give this a low rating. UPDATE: The M15i mysteriously came back to life. Not sure if it suffered thermal shutdown (note that the case was cool when it died the previous day). Currently sounds great, but I'm still going to return this one when the replacement arrives as I fear this may happen again. Do note that I'm still going for a replacement rather than a refund because I love it that much. 2nd UPDATE: Replacement M15i arrived and it has been stable. Customer support was good, although replacement took longer than expected to arrive. I guess replacements do not qualify for Prime shipping; I should have returned for a refund and then bought a new one (that would still qualify for 2-day Prime shipping). Despite having run into a shutdown issue on the first unit, this is still currently my favorite dongle dac/amp. It gives me the mobility I want while using some high-end IEMs.

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.

Great bang for the buck. I make use of both 3.5 and 4.4 balanced jack iems, and both hi and low gain and dac mode confirmation LEDs. Perfect with a good pair of iems. Would need very sensitive cans, which means usually better off with a larger amp for over-ear headphones. This is a DAC/AMP that I highly recommend. Note that it is fussy about the usb-c digital source cable connections. The included shorty cable always works, but many other (cheaper) cables won't, which may constrain use with some sources.

It worked well for a couple months but now it won’t turn on with my iPhone and does not work entirely for the phone. The audio quality was good but paying this price for something that won’t work after a couple months is not very good. This product is way too expensive for use problems. It was used very lightly and not damaged so there is no reason it does not work anymore. I am unable to reach out to questyle about the warranty replacement as they will not respond and there is no way to contact through Amazon it seems. I cannot sell it as I am unable to test if it even works anymore. Overall 2 stars for good audio quality but not any higher due to the quality control issues and lack of customer support. Not recommend.

The M15i delivers outstanding sound quality, especially when paired with a device that can provide full power over USB-C. I noticed a significant difference in volume when driving my unmodified DT770 Pro 80-Ohm headphones with an iPhone 16 Pro Max compared to an iPad Pro or Mac Studio. This suggests that a higher power delivery from your source device really boosts its performance. I'd highly recommend the Questyle M15i for anyone looking for a portable DAC with superb audio.

I use this to drive my focal clear mg headphones. I have used 4 other dacs. This is the best. It’s got plenty of power, sound great and has a very wide soundstage. Love it!

Chulada de dac/amp, para mover tus audífonos no tan demandantes está excelente si requieres mover algo más grande esta no es tu opción

Produto de extrema qualidade. Satisfeitíssimo.

Producía demasiada interferencia, se escuchaba ruido en tus audífonos.

I purchased it to replace an entry-level FiiO KA11 and I am really satisfied. I am listening to to music almost exclusively on Android, often through USB Audio Player Pro, with a Focal Azurys headset. It sounds great, balanced. Bit Perfect is supported, I am an happy customer for the most part. I was able to listen to this and the Cayin RU6, in the same price range. I personally prefer the Questyle M15i. Why not 5 stars? Because the USB-C cable provided is entry-level. It's very stiff, and the USB-C connector on the DAC is not solidly attached to the case but just soldered on the PCB. Whenever the cable needs to band, it puts pressure on solder joints and disconnect regularly. Everything is fine when I listen at my desk, but listening while commuting or walking is difficult: i need to keep the cable straight at all times and limit movements. I ordered another OTG USB-C cable that will be more flexible, with better connectors. Cable replacement isn't a matter of audio quality since we are talking about digital audio (it is either ok or it disconnects), but I need something that doesn't disconnect. Hopefully, the new cable will take the stress instead of creating some on the connectors. I wish the product didn't cheap out the USB-C cable...