1- Concerning the placement of the horn in relation to the woofer. It occurs to me that high freq waves travel faster than low freq. In a radical example if one were 1/2 mile away theoretically you'd hear the horn before the woof and the sound would be "out of synch". In a home envioronment the distance between speakers and ears is so short that this becomes almost unnoticeable I assume. But for those who pursue perfection, like me, I assume there's an ideal compromise to have the waves hitting one's ear at the same time. Course there's still the diff between very high and very low in the music which will occur no matter how they're mounted. Does that make sense and is it worth pursuing? Is that why the HF drivers are sometimes connected in reverse to compensate? Perhaps the solution is to simply experiment with the placement of the horn until it sounds just sweet. Maybe I'm full of it here. Not being a true audiophile I'm treading in unfamiliar territory and some of you have forgotten more than I'll ever know. What about an electronic device which could be put in line with the HF driver to vary the time delay? One could then just adjust it for best sound. If such an animal exists.

2- Damping the interior of the woof enclosure. What's the purpose of doing this? The theory. It's nice to know something has to be put in there but why? There is all sorts of stuff one could use including, I imagine, stuffing the space with toilet paper or kleenex but there has to be one material which has been shown to do the best job. So what is it? I'm not going to spend all this time and money building these things only to put anything less than the best in there.

3- Grille cloth. Assuming it's 100% acoustically transparent then I would imagine the choice boils down to appearance alone. True?

Thanks in advance for cluing in an old man who's tired of chasing after windmills.