Disclaimer: Fiio supplied the BTR3 for the purposes of review at Headfonia.com. That review will reference this page. The BTR3 goes for about 79$ USD. You can find out all about it here: FiiO BTR3.
As you know, I love the BTR1 and uBTR, but the BTR3 is a swing and a miss. Great measurements, yes, but physical interface/orientation problems and poor wireless signal catching make the BTR3 practically rubbish to use.
As you can see, it measures really well. It also hisses a bit less than an iPhone SE (next to nothing) through sensitive earphones like Campfire Audio’s Comet, and it sounds amazing. I wish that it didn’t also get great good battery life or work reasonably well as a USB DAC (in 16-bit 48kHz). I wish that because on paper it is amazing. But in practice, only the USB DAC portion works well, and that limited to 16-bit.
Get the BTR1 instead.
NL - no load
SM2 - Earsonics SM2
ES7 - Audio Technica ES7
DT880 - Beyerdynamic DT880/600
24-bit single ended @+0dB - all targets - LDAC
24-bit single ended @+0dB - SBC/ATPXHD/LDAC
Great idea, poor execution make the BTR3 one of the biggest practical failures I’ve seen among otherwise amazing-sounding devices.