The DEQX gives you what I call "lowest common denominator" sound. I was able to borrow a friend's DEQX and try it in my system since people think it is the audio equipment of The Second Coming. Even on straight through settings (no correction applied) the system took a big performance hit. The DAC's are just not as good as my CDP.
Although the DEQX can be used as a preamp, it is not a good preamp. The version I got to try had the optional analog volume control, and this was MUCH better than the digital volume control. You can easily hear the loss of resolution with the digital volume control - the sound was decimated and the quality is even worse than an iPod.
Another person tried running an analogue signal from a turntable into the DEQX and reported that the T/T sounded no better than CD. There are too many variables at play to definitively say if it was the DEQX which was blenderizing the sound but I suspect the ADC had a lot to answer for.
Digital crossovers are a very purist approach but you have to understand that it does come with certain limitations. No analogue sources for you - it will work, but whether it works well is another matter. Also, the DAC's in this particular DEQX iteration is no better than a low level CD player. If you have anything better than a mid-market CD player the DAC's are definitely better.
As with any hi-fi it is not a perfect solution. You get a performance benefit in some areas, but you also get a performance hit in others, and it suits certain types of consumer better than others. Good luck with your decision.
