they affect the upper highs only most of the time, only once have i had a set of speakers that didnt suffer from the grills. logically speaking, that makes sense because cloth is a good absorber of sound, high sounds suffer worst from environmental obstructions, ive never had an issue with bass and grill cloths, just highs. and yea, veiled is a good word for it, its almost like putting a piece of cardboard in front of it. this is one of the things that deterred me from keeping and using my KEF sattelites is because without the grills they sound fantastic, with them, flat, but the grills are metal covered in cloth like hot-dog bun shaped things and if you take them off it looks like half your speaker is missing