Room with glass windows as a walls.

@toddalin are those black-out drapes custom made or sold as a precut panels? Is color choice available?

there is no evidence that glass performs differently than drywall...except in the lower frequencies. 

the challenge with glass is that you can't really hang art or other things like you can with drywall...so you get bad flutter echo. 

Modern rooms also typically don't have carpet. I'm guessing this is true for your daughters new space....so rugs with carpet pads will help. 

Furnishings can also help. Again modern furniture won't be as helpful as it's typically reflective compared to soft and plushy. Clutter can also be helpful. You don't want a sparce room.

best of luck  

If she can afford to live in an apartment on the 43 floor .God Bless Her.. li

I’ve had my main stereo system set up in front of a large expanse of glass for 25 years. Always was advised to put curtains on the windows to tame the reflections, but I like to enjoy the view while listening.  What has really helped is to creatively find ways to listen in the near field with the speakers pulled out a bit from the glass. Took some trial and error.  Not perfect but sounds terrific.  And my adult sons absolutely don’t listen to my decorating or setup advice!

surfmuz

IIRC, they were from 3-Day Blinds.  Just measure and they make them to size.  Look for them on the web.