Posted by Jan L on July 17, 1999 at 16:53:14:
In Reply to: Acousticoil? posted by AG on July 16, 1999 at 10:58:51:
I don't have any experience with acousticoil for tuba, but I use one in my Bach Strad C trumpet. I have tried them in most of my trumpets, and they work great for specific applications.
On trumpet, you normally install it in one of two places inside the main tuning slide. It creates what the inventor, Don Novy, calls "constructive interference". Since I only play trumpet several times a week and don't have the young 'full-time' chops I used to have, my large bore Bach Strad C trumpet was too big for me. With the acousticoil in place, the coil gives you more 'felt resistance' making the large bore Strad blow more like a medium large bore. You can fine-tune the "constructive resistance" by placing the acousticoil either in the leadpipe end of the tuning slide, or in the valve body end. Placing it in the leadpipe end gives you the most 'felt resistance'.
At least in a trumpet, since you have more 'felt resistance' with the acousticoil installed, it is easier to control intonation, especially at low volume levels. The coil also gives you a little brighter sound and more endurance when your chops are weak. I used to use one in my large bore Benge Bb trumpet until I had a smaller bore leadpipe installed on it that achieved the same results as the acousticoil.
Don does make acousticoils for tuba, and as I remember, you can install one in the main tuning slide, or in any one of the valve slides, anyplace you need to add some interference. In a way, it sounds a lot like what Joe S mentioned about Dennis Brain's toothpicks. I have some intonation problems with my CC tuba, and I may contact Don to try an acousticoil in it.
Acousticoils are sold direct by Don Novy with a money-back guarantee. I don't know of anyone that was ever unhappy and sent one back. For specific applications, they work great for me.
If anyone is interested, I'll dig out Don's website address and put it on the bbs for the good of the order.
jan