Installation Instructions for Contrabass Chimes and mallet posts

Table of instrument dimensions

The contrabass chimes are the most technically demanding instruments to install, because the sounds they make require as vertical an installation as possible. This is due to the chime hanging most free from its internal lower bushing when it is plumb. The less contact the chime makes with the lower bushing (you can look inside the chime to see the bushing) the longer and better it will vibrate. Additionally, the installation will look best as a group if the chimes are all exactly vertical, therefore parallel. This will give a cohesive and sculptural aesthetic to the chime array.

The chimes are constructed so that the centers of the chimes will all be an equal distance above the ground when they are installed, provided that each support pipe is installed to a depth of 36 inches. An auger hole ten inches in diameter and 36 inches deep is recommended. In addition to the vertical orientation mentioned at the beginning of these instructions, each chime support pipe should be centered in its hole. You will find it useful to drive a ½ inch rebar stake into the center of the hole, (see photo #1).

This rebar stake should be vertical. The end of the support pipe is lowered onto the rebar stake, (photos #2 and #3). This system provides positive location to the bottom of the support pipe and makes it easier to brace the pipe vertically once the concrete is poured.

To assure vertical orientation of the chimes, attach a post level to each chime support pipe, (photo # 4). With the bottoms of the chime support pipes stabilized at the center of the hole bottoms by the rebar stakes, it merely remains to stabilize the support post vertically above ground level before the concrete can be poured.

The mallet posts will be set at the same time. Vertical orientation is not as vital for them. The top of the mallet post should be about 48 inches above grade when installation is complete.

Once the chimes are vertically stabilized, the concrete can be poured. Leave the post levels on until curing is well underway, as this will make it easy to verify that no drifting has occurred. Ensure there is no public access to the site until the concrete is totally cured.

The mallet posts should be located between chimes 2 and 3 and between 5 and 6. This will allow all the chimes to be playable. One mallet will be able to strike two chimes to its left and two to its right. ;Photo #5 shows the arrangement of contrabass chimes that I use most frequently. The longest chime is in the center position and the chimes alternate in length to the right and left ends. I have placed the chimes in a slight arc, but they also work well placed in a straight line. Photo #5 does not show the placement of the chime mallet posts, as they are not used in that installation.

The chimes should be spaced at 18 inches on center. The distance between chimes 2 and 3, and between 5 and 6 should be increased to 22 inches to accommodate the mallet posts. The hole for the mallet posts should be drilled in the middle of these 22 inch spaces.

Please also reference the Contrabass Chimes layout - PDF file.