Probably not talked about much due to the fact that most men don't get to choose - WAF rules. :-) But if I wanted to deaden the sound I would use lined wool. If I wanted to reduce the sound, as in making it diffused, about any other materiel would do so long as its not sheer.
Good Materials for Curtains
Has anyone made heavy curtains specifically to add absorbance to a room, and (of course) to block the reflections of glass? If so, what materials did you use. This is such a simple and common acoustical technique, yet I can find little written about what types of fabric (etc) are best. Thanks for your experienced suggestions.