The subject of this paper is, I am aware, a little outside of the usual programme of the Musical Association, as it deals partly with matters of building and architecture; but it is of some consequence that music should be heard under the most advantageous conditions, and some of those whom I am addressing may have to decide on some occasion on the choice of a plan for a concert hall, and I should be glad if I could think that any of the suggestions I have to make may be of use to them in the future. The construction of theatres for opera I am purposely leaving on one side; opera is a spectacular as well as a musical business, and the theatre is a special class of building, which would demand a paper to itself. We are here considering only the question of hearing music.