DDRC-24 USB DAC Digital Signal Processor

I've updated my review now that I have managed to get it working. The miniDSP documentation is poor, with lots of errors - mostly in the sense that information is out of date, but also because they did not cover the issue that I had (even though apparently it is known). The miniDSP software worked fine, but when it called the DIRAC LIVE v2 software to calibrate the room, it could not find the device. After much messing about and with excellent help from the suppliers (but no help from miniDSP who did not reply to my support emails on this), I was able to change the Mac OS port number by hand and get things running in a messy way.So now it works well - the sounds is greatly improved - much clearer and much better stereo separation. I have not yet managed to find an optimal target frequency curve - it would help a lot if DIRAC could supply a range of typical curves - but it is still very good already.So - overall - four stars - though nearly down to three, as this is a very expensive bit of kit for what it is, and how poor the software and documentation is (and lack of support from miniDSP).