preamplifier after preamplifier?

We suggest keeping the system as simple as possible, with one preamp, our choice is the miniDSP SHD, it would integrate like this:

Here is the functional block diagram,  this allows for full control over all crossover slopes and frequencies, channel levels and delays.  Most importantly, Dirac Live room correction.

@deer_creek_audio 

Thank you for posting this suggestion. This is a really intriguing solution. I have been looking for something that will provide better subwoofer integration and possibly room correction. The McIntosh MEN 200 does something similar, but it is significantly more expensive and it doesn't provide this level of adjustment. 

The miniDSP SHD works well, I can add from my own experience. So does the Anthem STR Preamp, which has similar functions and a nicer interface, but costs twice as much, lacks a streaming network input, and is currently very difficult to find.

Other candidates might be some units by Lyngdorf and the DSPeaker X4. I have not heard the last two. In general, as @deer_creek_audio pointed out, a DAC-preamp with DSP including crossovers for subs is a great way to configure a system with subs. It can give the fine control of LF response that is impossible to get in most rooms any other way, so excellent sub integration and flat response in the low frequencies.

P.S. Some of the new NAD gear is similar in block diagram, too, and might be worth considering if you want to go in this direction.