Drum Risers, Who has built them? What works best? Options

[Synthetic]

hey... are there any recording people out there that have experience with drum risers? I am looking to build one in my basement but trying to decide if its really needed since floor is concrete foundation.

I have seen plans for both closed box and ones for open air designs. I have heard that it can be hard to build a good sounding riser and wondered what might be the best way to go? It seems like a closed box design would act as a resonating box itself coloring sound even more but the open air design where the platforms sits on legs seems to me like a better choice. Anyone have experience with this or offer up any advice?