If I were advising someone to try this path I would advise them to get a MiniDSP UMIK-1 or 2 which is a simple but high quality USB microphone. Using a phantom powered mic can be more accurate but it is trickier to set up in Room EQ Wizard. Whereas there is a profile built in REW for this mic and the instructions are very clear how to set up and make accurate measurements quickly in the REW literature. I used a loop back timing reference before REW had the ability to use the high end of a main speaker as the timing reference. Once the sweeps are made with each speaker at the listening positions and named appropriately you can go to Multi Sun Optimizer and just follow their instructions on creating a project and use your data rather than the data included in the project and you’ll see how it all works and get a nice result quickly. After you understand how the filters work you can start to tweak them to get the best result.
I am of the mind buy it once buy it right so I waited to get what I wanted and bought a lot of things used. It took a lot of patience but I think it paid off and wouldn’t change that either. I like having two pairs of matched subs that support the system at different ranges. I think the affect is more dynamic and having four subs is critical to countering the room issues. I started with the Mini DSP platform and they make a good overall product. I prefer IIR rather than FIR filters due to the lower processing requirements of the IIR filters. If I were to make FIR filters with 12 coefficients the processing power needed would overwhelm the processor and would require less coefficients and be less effective overall.
It is scary to plug your amps directly into the speakers. Labeling is key and it is so important to start playing anything at -40dB so nothing gets damaged if wires are crossed. The power gain and immediacy of the amps plugged in directly is pretty awesome. They don’t have to push any power through passive components all of it is used just where it is called for. The dynamic range is increased and noise floor lowered when the only D/A conversion happens at the output to the amps. The main disadvantage to making an active set up in my opinion is that you need all components for it to work (amps for each channel/speakers with by-passable passive crossovers/DSP/computer). It’s hard to start with a few simple components and upgrade to more/better/all in one designs vs. separates etc. In spite of that you can start out with the basic set up and upgrade the mains, subs, and amps as money and opportunity presents themselves. I think the benefits to an active set up with room correction can far outweigh spending more on one pair of good speakers if compromises have to be made.
Thanks,
Steve