I couldn't deny that what he made was good or better than mine. As I am very much inclined to horn speaker system after I got the 604B, I am asking his advice for my system. It never happened before when I couldn't understand what he was trying to do.
Hi Sanhanul:

604B can work well but I found 604 to be a tricky speaker to tune for home use.

I think your friend taught you one of the lessons of horn systems: BIGGER IS BETTER!!

2 or 3 way with 12" or 15" woofer might be your next step!!

This is all pro gear, often designed for theaters, and sometimes adjustments must be made for small rooms. WE and Altec engineering is a very good start.

Have fun!

Joe Roberts