I made a set of inverted horn enclosures for 15 inch bass, 6 inch mid, and 3 inch piezo twitter in 1982 or 83. The port path was over 6 feet (it's been too long to remember) whatever 20 Hz frequency measures out to... With only 20 watts they would shake the windows next door and the drums sounded real like a live band. Wish I hadn't sold them.
But they were 3/4 birch plywood and I never had a problem with them rattling or vibrating. The build was very solid though with lots of internal bracing where the horn folded inside.
But they were 3/4 birch plywood and I never had a problem with them rattling or vibrating. The build was very solid though with lots of internal bracing where the horn folded inside.
