I've been using KX-Project in my loudspeaker design hobby. It's a very friendly and flexible environment for prototyping and learning. Comparable commercial platforms are way too expensive or impracticable for home use. I owe a lot of what I have learned over the years to KX-Project. It was the initial spark that helped me experiment with audio and the platform on which I test concepts and ideas. Ardor - Point source monitor This is my current project that uses KX-Project exclusively for the crossover. It's a high-fidelity loudspeaker that is hard to compare with anything else currently on the market. If you have interest in the field you might want to check on my progress again soon. I'm experimenting with ways to obtain near-linear phase with KX-Project.