Quote Originally Posted by kexodusc
Interesting - if it was speaker cabinets and vibration/resonance damping we were looking at, MDF, 7-ply birch plywood (or oak) would be preferable materials to wood, and likely cheaper.
Harder shelves would vibrate less so I'd go that way for isolation - MDF is tough to beat, but HDF is even better. Veneer/vinyl/painting required, of course.
Good quality plys are pretty rigid and an option as well.

I dunno about plastics and fiberglass, there's probably options out there of course but I'm guessing they're not cheap or easily available.

I built my last rack with 3 posts. I found the single rear post in the middle looked kinda cool, but honestly it's a real pain getting at cables and I wouldn't do it again. If you're sitting a processor or receiver on there, you will want the extra room. Don't be cheap, go with the 4 posts. Worth it IMO.
Well I was quoted a price of $18 a square foot for 1 3/4" butcher block ash wood shelves. As many as I want. Maybe I'll order 7 of them...