I noticed today that this product is finally for sale, and it looks really ideal for speaker designers. The price isn't too crazy either, considering it is complete with a 4ch amplifier. https://www.hifiberry.com/beocreate/
You can set up with a raspberry pi to play music or whatever test signals remotely over wifi, and then program the DSP remotely over wifi from your couch. I'm inexperienced with Sigma Studio, but if it doesn't spit out a final transfer function of the filter, you can measure the sweep the output of the DSP fairly easily to determine a transfer function, then if you want to go passive all you have to do is come up with a matching transfer function.
I'm not deaf, I'm just not listening.