What does the F3 Fc and QTC stand for in jl's 12 w3v3-4 sub box specs?

Question

What does the F3 Fc and QTC stand for in jl's 12 w3v3-4 sub box specs?

Answer 1

The f3 is the 3 db down point this is 3 db down from 0db it is a reference point used for the freq response of a driver in a particular enclosure.

The QTC is the total damping of the sub and enclosure the acceptable range for this is .5 being the largest and 1.5 being the smallest the optimal range for car audio is .707 - 1.0 this giving you the best low freq extension and power handling

for more info on this go to www.orion.com the have a very informative section on enclosure design.

Answer 2

F3 is the 3db down point.  Fc is the resonant frequency of the system and QTC is the relative damping of the system (electrical and mechanical).

Answer 3

http://www.usenclosure.com/Enclosure%20F...