Just curious, I have an old Longcase Grandfather clock. The bottom of the case is mostly open. Would there be a difference with the sound of the chimes it it was closed? I thought the sound might be richer is closed. Advice appreciated, thanks.

I think most of the difference in sound depends on where the chime block is mounted. It is that piece of wood that acts as the resonator. The sound is then carried to other surfaces that conduct sound. For example, it might sound better on a wooden floor than a cement floor. The difference may be minor. I think the case itself is the major carrier of the sound.

In smaller (shelf) chiming clocks it makes a significant difference if the clock is on a nice wooden surface, as opposed to sitting on some other surface.

My initial thought is that the open bottom would allow the sound produced by the backboard (where I am guessing the chime block is mounted) to flow into the room. The backboard would be the main resonator.

The chimes are mounted on the back of the case. The case was closed, but it looks like the weights at one point fell and broke the bottom. I was wondering if it was worth cutting a piece of wood and placing it on the bottom. There is one quarter left on each side, about half of the middle is missing.

Mark, I don't think it would make much diference in sound. It may keep some dust out, and that may be the biggest benefit.

Thanks, I put a piece of pine board on the bottom. Really can't distinguis a sound difference, but there should be less dust. Thanks for the replies.