The experiment has been run, and here are the results.
The Boston Acoustics speaker weighing ten pounds was suspended by a single rope, so that it was about ¼ inch above a table top..just about ear level for a seated person. The center of the speaker was 63 inches from the pivot point in the ceiling, and the period of pendulum swing was measured as 2.5 seconds, which is 0.4 Hz. Loud organ music was played
as loud as the speaker could handle.
Because of the way the speaker was hung it never completely stopped swinging at 0.4 Hz. The motion was about 1/8 inch peak to peak. (The motion was easy to evaluate because the speaker was ¼ inch from the table top). This was with no music playing. If I were going to hang speakers permanently I guess I would use three ropes/chains.
When the music started the small motion of the speaker was very carefully observed for any change relative to what was happening before. There was absolutely no effect as a result of playing the music. The test was repeated about five times.
This is the first time I have hung a speaker in many years, and although when I did I never was conscious of them moving, I must admit that I never looked for movement at the level of this experiment.
By the way, the little box sounded much better than I expected, and I think that I have solved the problem of where to put the rear speakers in my HT set up. Up till now the B&W 550s have just been kicking around behind the couch.
