Equipment rack with hollow tubes.

I bet you can’t hear hollow tubes ring even when you put your ear right up to them. It’s an old wives tale. I know what you’re thinking - but if I strike the hollow tube with a small hammer I can hear it ring. Solution: don’t strike the hollow tube with a small hammer while music is playing. 😛 Sand filled speakers never really caught on either for the same reason. If you’re determined to prevent ringing more elegant solutions include wrapping 2” length of the tube with viscoelastic tape or sending the tubes in the cryo lab and/or filling about 1/8 of the tube with hollow fiber wool.

@elizabeth @geoffkait .....Thanks...... I just did the test with a small hammer while i had my ear on the tube. I did not hear any ringing. I just heard a little bang from the hammer. Maybe it depends on how thin or thick the tubes are. If i did hear a ringing i would of filled them with sand also. But since i did not hear a ringing i will just leave as is.