No Art the room would not sound dead. Homasote is used in Radio/Television stations, & Recording studios. It would serve better than 2-5/8" layers of Drywall. The problem with homosote in the inexpensive variety is just natural burlap, & not very attractive. Homasote also has to be installed using screws, & washer type collars as it is very fragile. There is no way to hide the seams between the panels other that some type of paneling strip. Also it can't be painted otherwise it defeats its purpose. The inexpensive variety was about $28 dollars for a 4'x8' sheet 9-11 years ago. It gets crazy in price once you get dyed specialty colors. The worst thing about it is your room may look very industrial, or much like a 1970's D.I.Y. conversion van paneling kit project?
If you intend on doing it yourself, you will only need a straight edge, & a carpet knife. You will need to replace the blade for every 2nd, or 3rd completed cut. As you need to cut the finish side first all the way thru. It isn't as easy as drywall. Also keep it atleast 3/8-1/2" off the floor, as it is more moisture absorbant than Sponge Bob. Since your probably going to cover the floor to wall seperation with baseboard? You must wear a dust mask, & get a shop vac ready as it is very messy. I would also use a 1/4-3/8" bead of adhesive caulk behind each central portion of each panel such as Pheno-Seal. It is less permantent than liquid nails, should you ever want to remove the Homasote. Pheno-Seal also has no odor/smell like silicone based caulks. With the caulk you may only require 6 screws on the side edges? Lastly I don't believe there is much, if any type of fire-rating on it so that must be taken into consideration also. Good Luck!
