FiiOBTR17 Bluetooth 5.4 USB DAC AMP with LDAC, aptX Lossless. Dual ES9069Q, 10-Band PEQ, THX AAA 78+amps 3.5mm Unbalanced & 4.4mm Balanced (Black)

Great DAC, great battery life, never lost signal, easy to connect to the transmitter I used, could be louder but worked for me in my environment. Easily fits in my pockets and functions as intended. I do have to say that in conjunction with the ugreen BT transmitter, either the ugreen or the uii clamped down on the sound gate which ended up clipping inbound sound when the gate lifted so the few half second or so of transmission was lost unless I kept a very low signal going and the gate wouldn't shut down. Sound was clear, no detectable loss of fidelity.

This is awesome!!! I use other less powerful bluetooth DACS including a couple from FIIO that really improved sound on the headphones I use, primarily Sennheiser 560s, 598s, 580s and 650s. Both the 580s and 650s are high impedance compared to the 560s and 598s. While they made the 580s and 650s sound much better, I didn't really think they were worth the extra money I paid for them and I came to believe the legendary 650s were over-rated. I received this last night and went first to my 650s for a test drive and this has completely changed my mind about 650s. It brings out the best in them such that they are now my favorite set, a fuller sound with more definition and expansion of a 3d effect, great details that aren't drowned out by bass or mids, much better dynamic range. This unit is easy to use, has a convenient and well tapered volume control, the size is very manageable and it comes with a case that clips to a belt or belt loop. It provides more power and transparency. This is a must-have if you utilize high impedance audiophile headphones and enjoy portable listening (my source is my Motorola Razer for both streaming and stored MP3s). I don't see how you can beat it for the price.

Bit of a preamble. I'm not one to prefer Bluetooth, and in fact I usually don't. Speaker technology has advanced so that even $20 earbuds from the right brand can sound amazing out of the right source, but when you try to stuff a Bluetooth radio, micro controllers, a dac/amp, buttons/controls, battery in a package that fits in something the size of a gumball, things get rough. Bluetooth hissing that's usually hidden by cutting power to the amp when audio isn't playing, issues with the dac output being low resolution, you name it.In short, this device is amazing, because it solves all that. Good quality Bluetooth hardware in a pocketable form factor. You technically have a cable, but if you care how your music sounds this won't matter- it's not tethered to the source device after all. This outclasses every Bluetooth earbuds I've ever used even when paired with aforementioned $20 bargain buds from a good brand, and I've had the likes of Sony XM4 and others in that class. No ANC naturally, but certain IEMs or even over ears can easily work like plain old ear plugs and when the music starts the world disappears anyway.Battery life is quite good so far. Nonstop use for three hours on the LDAC codec and only down 80% on the first few runs. Will speak more on this as time goes on.Pair that kind of wireless performance with the ability to wire this in as a wired DAC(not to mention the microphone so you can take calls even on HD600s without needing to get a potentially problematic inline mic cable), and it's all around the perfect device to get Bluetooth conveniences on any headset, or even just to wire in and improve your laptop's sound output. I view it as a swiss army knife of portable audio, and as someone that can't buy most Bluetooth headsets within ending up unhappy, I fully recommend this. Regular Bluetooth headsets live and die by their batteries, but this can be permanently wired in as a USB DAC should its battery suffer the same fate.

Looks nice and seems good quality built, I love the size and firm seat of the balanced jack. Great sound in direct through channel on sennheiser HD660S2, good Bluetooth functionality, multiple USB connections are also a useful feature. Other equalizer settings are not helpful - at least on better headphones. It’s a surprisingly light device, almost feels empty inside. But disappointing battery life, barely lasts a transatlantic flight. While other software functionalities may be useful for some users, I rarely use any, including the hardware switches. The leather cover is good for protection (faux leather I guess), but slips out too easy. Would not buy again (not for 200 at least) almost entirely because of battery life. I have no experience with other HDACs, though.

This thing is awesome! Works great! Sounds great! Easy to use

Best in class portable headphone/IEM amplifier DAC. Sound is pristine. Controls are better than competing devices. I use this with a computer as well as for summer and winter sports. I use both the balanced and unbalanced outputs. Battery life i excellent, I typically get 9 hours plus at moderate volumes. Recharging is quicker than most. Build quality is superior.In short: If you're good with a palm-sized earphone DAC this is the one to beat.I bought the blue. Comes with a leather case with a securing belt strap.