The Grill Effect: Woofer Covers (4)

Reliable Hardware quantifies how acoustically open their various flat stock is. The more open to air flow a grill is, the less it reflects output back at the cone, and the lighter it will be for its type. I would never recommend anything less than 50% open. expanded diamond cut - 63% open perforated 5/32" round hole - 62.4% open and in distant third: perforated 3/8" square hole - 56.2% open After doing a lot of web crawling these seem to be the way to go for full-coverage metal jackets. My preference used to be the expanded diamond cut, but the 5/32 round hole grill has taken its place. Downsides to Reliable? Minimum order there is $25, and shipping for only one grill is rather high. So you may want to order something else there too