I've tried a few things with setting up my Flex so far, and I thought I'd share my results. I'm also curious to hear what other people are finding works well. My setup is near field with Revel M105s and dual 8" subs in a small treated room (about 115 sq/ft with 8' ceilings).
My first attempt was to follow the manual exactly, and it turned out bad. It said to leave the sub crossovers off. My subs don't have crossovers (that's what the miniDSP is for), so they will try to play whatever you send them. This seemed like a bad idea. It also said to not have any DSP filters active at all. I don't know much about Dirac, so I did what they said and just let it rip. When it was done I set 80 Hz 12dB/oct crossovers and ran a sweep with Dirac on vs Dirac off and here is what I got:
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It's better than no correction, but I was not impressed at all. I can get better response and sound quality with DSP alone, and I think the problem here is that Dirac runs BEFORE the routing, so it don't split the subs from the mains and has no idea I have subs. For my next run I sat down with REW for a couple of hours first and carefully crafted DSP filters on all of the 4 channels after setting the crossovers. This is where I landed compared to Dirac.
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And not surprisingly to me, my DSP filters were better than Dirac, hands down. Not just in comparing measurements, but it sounds way better. With the room response better dialed in with DSP and crossovers, I then Dirac directly on top of this without disabling any of it, and here is how that turned out:
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WAY better! Doing it this way, Dirac offers a noticeable improvement in the measurement. The nulls are handled much better, and the response is smoother overall. In subjective listening, I think it sounds way better with Dirac. I don't know how to describe the sound with flower audiophile review language, but the difference is dramatic and I'm very happy with the result at the moment. That said, I just finished this about 20 minutes ago and have a lot of listening to do.
Here is a final comparison of me setting DSP+Crossovers first then running Dirac vs just running Dirac on it's own with no DSP or crossovers set first. I did not attempt to DSP after running Dirac, but I might get around to trying that too.
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