i’ve used them. they’re not bad, but asking that speaking to even attempt to play 50hz is bat shit crazy. look. here’s the move- buy a Wiim Ultra streamer and a powered subwoofer. use the usb output of the Wiim to feed the D3V’s usb input and the sub output to feed the sub. crossover at 80hz and use the built in room correction. you will have a legitimately good monitoring system. don’t cheap out on the sub. buy something sealed if possible.