Richard; I queried Louis about this question and here is the Summary:
The frequency response for the Type 1 is 60 to 18KHz sealed; and 48 to 18KHz vented.
The frequency response for the Type 2 is 50Hz to 18KHz sealed; and 38Hz to 18KHz vented.
The frequency response for the Type 3 sub is 27Hz to 150 variable and sealed only.
The frequency response for the Type 4 with the sub built-in is 27-18KHz. Louis would keep the upper section of the type 4 sealed.
I hope this helps you determine which model fits your room/system.
Cheers, Hank, Super 5 owner.