I have wood blinds behind my speakers, never experimented with partial opening, unbelievable! Will have to try this weekend.
Closed, they are reflective, it will be interesting to note the amount of added diffusion when partially opened, something I've been looking for. It does seem that the diffusion properties would be somewhat limited by the window behind being in such close proximity to the wood blind. In the summer the storm window can be pulled out, I suspect the added space behind would increase the diffusive properties. I also have cellular shades on one side wall, these absorb sound, however, not to the extent of my Echobusters.
Closed, they are reflective, it will be interesting to note the amount of added diffusion when partially opened, something I've been looking for. It does seem that the diffusion properties would be somewhat limited by the window behind being in such close proximity to the wood blind. In the summer the storm window can be pulled out, I suspect the added space behind would increase the diffusive properties. I also have cellular shades on one side wall, these absorb sound, however, not to the extent of my Echobusters.