Music performance, a ``momentary and spatial art,'' is finally completed in a concert hall. Even with the same elements such as a musical instrument, a piece by a composer, imagination and technique of a soloist and their co-players, totally different music can be created according to the acoustics of a concert hall. Before a concert, players carefully grasp the acoustical nature of the hall and adapt their technique to harmonize with the hall. When players are successful in their adjustment, they, together with the audience in the hall, can truly create art. As is often said, a concert hall is the greatest musical instrument and, as such, its role in the performance of music cannot be underestimated. This fact demands attention and is worthy of far greater discussion by players, acousticians, and architects. In this paper, a consideration of concert hall acoustics is described from the standpoint of a violin soloist.