FIIO BTR15 Hi-Res Certified Portable Bluetooth DAC & Headphone Amp

BTR15 is a great DAC/AMP for phones without a 3.5mm jack allowing you to connect high fidelity sound from your phone to your headphones again like the good old days. The BTR15 has a warm note(very small bass boost) on flat EQ settings that makes songs sound fun to listen to instead of flat and analytical, however this can also be set(flat and analytical) if so inclined. Plugging headphones or IEMs into the BTR15 and you have mountains of volume to work with as the Low Gain and High Gain mode give you a large range of volume to play with maxing out at 60 clicks in Hig Gain mode. There is a function in the Fiio Control App to limit the max volume cap preventing unknowing users from blowing their eardrums accidentally. The BTR15 has a longer lasting battery than it's competitor the Qudelix 5K when using the AAC or AptX Bluetooth codec, else with the LDAC codec the audio sounds slightly better(slightly improved bass) but battery life is reduced drastically about 8-10 hours to 6-8 hours with LDAC, also if you are not using anything like a 60 Ohm or higher headphone or balanced plugs, change the Gain to Low to save on battery life. The Power and Multi function buttons above the volume rocker of the BTR15 are quite small and can land in between your finger and fingernail with the clip case installed making it slightly annoying to get to the menu or turn on the screen. In comparison to the BTR15's competitor the Qudelix 5K, it has a few advantages; it has an OLED screen that shows battery status, volume level, gain mode and Bluetooth codec used along with bit rate, 5K has no screen, BTR15 has 4.4mm and 3.5mm audio jack for standard end and balanced headphones, 5K has 2.5mm and 3.5mm audio jack for standard end and balanced headphones, can use BTR15 without installing the Fiio Control App, 5K requires the app to setup device. Short-falls of the BTR15; Qudelix 5K is 3 quarters the size of the BTR15, BTR15 comes with a plastic holder with a belt clip, 5K has metal built-in clip, BTR15 stays powered on when paired with a device even if no audio is playing till it either runs out of battery or you manually turn it off, 5K has a setting you can adjust when audio is not playing that will power off even when paired to a device, BTR15 Android App feels like it is still in beta, is minimalistic with settings and always displays a loading screen if you change a setting of the BTR15, 5K has a robust Android App with well explained functions and explanations for what certain functions do, has recommended settings and is a very detailed and feature rich in settings even allowing you to control how long the LEDs in the buttons stay on for.