Acoustic treatment for side glass doors / please, need ideas.

You're not worried about the glass glass which you use for your Scotch? It's a primary reflection point since it's in that sweetest sweet spot. 

Best place to start would be something like a Mapleshade brass or maple scotch tumbler.

On a serious note, I'm dealing with a similar issue. The far wall is mainly glass windows, and the designer just doesn't get it. I'll be using a 15-inch woofer as shield for the Tuesday battle, err meeting. Their recommendation is to do nothing...to let the beautiful light in. Since it is three against one, maybe 2 and a half since one of the designers is moderately sympathetic to the whole audio thing...anyways, you know where this one is going.

Curious to see what is recommended. I'm considering GIK free standing panels that can be moved out of the way easily. Though I'm sure I'll need to get designer sign off on the fabric color.

You might want to look at groffkait's website, he sells very small adhesive copper strips, that tune the glass, highly effective & inexpensive, work well with pretty window treatments.

Don't do anything until you've setup your system in the new room.  It reads as if you're speculating about a potential problem.  Wait until you find out if it's a real problem.

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