Probably the guy who is the BEST in the world concernig that speaker is Bill Miller of Miller Sound. I think he is out of Philly. If you respond to this, I will get the number from home tonight and send it to you. I heard a pair of RS1b's that he moded, ALL driver and the crossover, and it was one of the top 2 or 3 speakers I have ever heard, including things like the $70K Logans and the such. The RS1b with his changes was superior.
Mike
Mike