The dolby lake may be meant for SR, but I do know of a few people who use them in 4 way speakers since it has good fidelity, is very flexible and low noise.
I was agreeing with you, that the only ones available are cheap digital, expensive digital or expensive analogue (Marchand for example). There isn't a low price point decent analogue version out - at least that I've found.
However I suspect the number of people who'd want one (either digital or analogue) would be in small numbers
Funny you should mention Marchand. Buddy of mine uses one with his Magnepans. At one point, he was using Krell / Bel Canto and than shifted gears to some tube amp (CRS) and later an EMO mono on the Bass end. It's difficult to keep up!
Trouble with marchand is you must know IN ADVANCE what you want when you order the modules. Also, the MINI products have various time delay adjustments and even 5 band of Parametric (PEQ) per Input and Output. I do not know what the current module price for Marchand is, so that's a factor, too, especially for the DIY guy.
It might be feasible for the straight DIY guy to use MiniDSP for initial setup than convert to Marchand when the crossover parameters are stable? I don't know how that would work out in reality.
Some models of MINI also can use FIR filters which have NO phase shift thru the passband.
I'd have to look over the Dolby Lake capabilities since the ask is so huge that it must be Vastly Better than the alternatives, especially for the home user.
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