Room Question

I’m making plans to finish part of my basement and move my system from the family room to the basement. The finished basement area will be in an L shape with one section being 15’ by 18’ and the L section being 12’ by 15'.

In the 15’ by 18’ section, there’s an off center 40” wide HVAC duct that runs the entire 18’ length. The 90” high ceiling in the 12’ by 15’ section is flat.

My question is… would it be smarter to use the 12’ by 15’ section for my system or take my chances with the off center HVAC duct?

I faced a similar situation and went with the smaller section for my system. The primary reason being the end result seemed more like a "real room".
Love my space, but have come to wish it were a tad bigger. Thus have been toying with the idea of tearing down the interior wall which formed the L and using the whole basement space. Not ideal in either case.

Considerations that come into play, the size and type of your speakers etc. Will your music room also be for television as well as audio? Short or long wall for listening and or viewing? Account for your expected seating for the room.

The expected use for the rest of the family in my basement conversion did not materialize as I had expected. Wish I had been a little more selfish.

Post your result, would be interested to know.
Glenfihi... The “rest of the family” that’ll use the finished area is the five grandkids. After more coherent thinking, it dawned on me that one of the things I want to accomplish is to have a room that allows me to put some real space between the speakers and the back wall… so I think the answer to my question is to use the larger 15’ by 18’ foot section for the stereo and the smaller L section for a TV area.

This project will for sure turn into the proverbial BOAT, i.e. Bring Out Another Thousand $... since I’ll be adding a 2 channel amp and preamp to my Theta system.
I think it would make your life easier not to work around the duct.It could be done,but not worth the trouble for 36" of space IMO.
if you place your stereo system in the basement, i'd advise a carpet and ceiling tiles. i have no opinion on the other question.

you may need to treat the are behind the speakers, as well as at the sides of the speakers.