Digital crossovers?

You might want to look into the TacT gear.

These are good up to a certain level. Once you get beyond a certain price point the built-in DAC's in these units are not as good as aftermarket DAC's. The other disadvantage is that these are PCM only, so no DVD-A or SACD. Also, if you want to use an analog source, you will have to run the signal through an ADC.

The advantage is the very steep crossover slopes you can achieve - up to 300dB/octave with no phase issues. Such steep slopes are unheard of in the analog crossover world ... well not without major problems.

You can also correct room anomalies digitally. This works by finding the null point in your room and subtracting all other frequencies to match the null point. In some cases you may find that you do not have enough gain, but I have been told that on some units it is possible to modify the op-amps in the output stage of the DAC to provide higher output if necessary.

I've been bi-amping with a TacT RCS2.2X for 3 years. The previous format was a Placette passive Linestage and a modded Dahlquist DQ-LP1, which combo proved extremely transparent. What very slight loss of transparency was experienced has been more than compensated for by the ability to make room/speaker/woofer corrections in the time domain, choose a 60db/oct slope w/o phase shift, and smooth my low end frequency response(in the room) to with +/- 2db from 20 to 250hz. No losses whatever in sound staging, imaging, immediacy, or timbre, but rather a much greater sense of being present in the recording venue. Some of which I have(as a reference).

Take a look at Meridian's DSP loudspeakers.

Kal