Speaker grill material, any real difference?

Granted anything will affect the sound, I like the way they sound with the grills on. Actually the manual states to leave them on as well. I think since these speakers have both planer type and cone type drivers the cover helpes blend the sound properly... Maybe?
"Single strand double knit polyester?" Sounds like one of my old disco shirts. I'll check it out, as well as the standard issue stuff.
-JD

Speaker designers final voice their speakers with the grills on....therefore, the fabric will make a difference. Take a sample of original grill material to your fabric store and ask for a duplicate material with similar weave.

Some "grill cloth" is more accurately described as "acoustically translucent" not "acoustically transparent".

Using whatever the speakers were designed for would be prudent.

Not to miller the thread, but what type of adhesive do you recommend to attach the cloth to grill frame? Im thinking of re-doing mine (manuf. says $400. for new ) but unsure of best adhesive. The frames are metal.

@Wino- A thin bead, from a hot-melt glue gun. Work fast, as the glue cools quickly. Trim excess material with an X-ACTO #1. Done correctly; it's a whole lot neater than any other method.