Currently all Crown amps have some kind of conversion and processing that can't really be turned off, that includes the XLS series.
The input section uses the ON Semi MC33079. But much of the signal path is contained within our own proprietary IC, which takes the place of thousands of discrete components, so the signal path is very simple and elegant.
The codec is the A/D and D/A, which in the 1500 is a discrete IC. The discrete IC will give better performance in terms of THD+N than the codec integrated in the DSP.
The XLS Drivecore series is state-of-the-art and very well-suited for home applications because of its low noise, low current-draw, and very low fan noise.