Well for one thing...Originally posted by Earl K
You and I went through this a couple of forums ago. What TS numbers were/are wrong. I remember you reporting that JBL said to measure it yourself,,, etc. The numbers I use seem to give the appropriate curves for this class of speaker. Here's a pdf of a 2 cu' , 50 Hz tuning I did quite a while ago ( ignore the date stamp ) . How does this curve compare to what you see with your tuning-prediction software?
regards <. Earl K
Given a value for Fs of 35 Hz, Mms of 0.055 kilograms, and Sd of 0.090 square meters, Vas SHOULD be ~427.7 liters instead of 274.7.
This is given by:
Vas = (2 * pi * Fs)^2*Mms)^-1 * p0 * c^2 * Sd^2 * 10^3
Where Vas is in liters
Mms is in kilograms
p0 is 1.18 kilogram/cubic meter (mean density of air)
c is 345 meters/second (speed of sound)
Sd is in square meters
I think using 427.7 instead of 274.7 jacks up the reference efficiency though... I'd have to work through it...