The sound produced by the M Scaler is brighter, tonally bleached, lean and artificial. It removes the natural warmth and fullness of recordings and adds an artificial sense of detail. People hear this impressive difference and think it must be an improvement. It’s not.
The M Scaler is no different to upscaling through Roon or other software. Rob Watts adds some proprietary sauce to make it sound a little different to Roon but it is essentially the same thing. There is absolutely no reason why a PC cannot do what the M Scaler does, despite Rob Watts’ claims.
There are no free lunches in audio. Massively upscaling audio files to 768 Mhz does not just turn them into the equivalent of native ultra high resolution files and does not come without cost. That cost is the bright, lean and fatiguing sound that the M Scaler produces.
Rob Watts claims that the DAVE/M Scaler reproduces transients better than any other dac, but this is audibly not the case. The DAVE/M Scaler produces splashy, two-dimensional transients which sound artificial, and can be bettered by many other dacs.
The gullible Chord fanboys on Head-fi have drunk deeply of Chord Kool Aid, but make sure you form your own view before buying one. Definitely don’t fall for the old trap that if it sounds different, or if it appears to produce more detail then it is better, because it is not.