[Xenon]

Originally Posted by terry j

Not from what I see, have a look and count in the links you made earlier. Yeah there is a half width on each end, but taking that into account there is an even number of wells.

Duh! I missed that...

Originally Posted by terry j

Can we have a prime that is even?? (hahah, of course, two, silly little joke there.) that was why it 'jumped' out at me when I quoted that little bit earleir, forgot to give a link http://www.rpginc.com/commercial/pdfs/QRD_Modffusor_Comparison.pdf clearly states 'no longer bound by prime numbers'

Thanks for the link. Yeah, I've been reading this and that from the googlebooks limited preview of Acoustic absorbers and diffusers: theory, design, and application By Trevor J. Cox, Peter D'Antonio (2004). There's quite a lot of discussion about optimization. In the PDF you sent: "RPG’s advanced patented QRD, which is called a Modffusor, because it’s design is based on a modulated, optimized diffusor as opposed to the older number theory approach..." Also a 14% decrease in depth, RPG writes. It's my understanding that optimization takes many forms, but involves complex math and also acoustic measurement of prototypes (as with certain informed well designs which have no fins). How does the Modffuser work with 8 wells? Neat.