My question is, what is the ideal QTC in a sealed enclosure for 100% SQ with SPL not being a factor. Some say .707, others say .5. Also, are there any formulas to figure out the QTC of my enclosure. I don't want to use a box building program since they are not accurate. I am pretty sure I seen a formula to figure out the QTC, but can't remember where. Thanks, Dave Last edited by FaintReality at Sep 21 2002, 03:20 PM
The actual formula is: Qtc = Qts X (Square Root((Vas / Vb) + 1)) Most box programs get it right, some don't.
I used this formula: You substitute any Qtc between 0.50 and 1.50 in place of 0.70 in both equations (both must have same value) to experiment with enclosure size. For Vas, use ft^3 not liters. Find alpha: X = (0.70 / Qts)^2 - 1 Then calculate enclosure volume: Vb = Vas / X After reading and speaking with Dan, I have decided to go with a QTC of .577 to achieve the best transient response, and it will make the best of my 500w rms to each Brahma (JL 500/1 amp for each 10" Brahma). With all this stated, I substituted the .70 with .577 in the equation. I got a final Vb value of .69ft^3 to achieve a QTC of .577. Is this correct? 10" Brahma QTS=0.41 10" Brahma Vas=.678ft^3
I found an online calculator which gave me an enclosure volume of .691ft^3 to achieve a QTC of .577, so the formula I posted above was correct. With this in mind, I am assuming I would have to subtract 3L (0.1059ft^3) for driver displacement and for any bracing correct? The .691ft^3 is what I want to achieve once the speaker and all bracing is enclosed in the enclosure? So, for example, if I didn't use any bracing, I would want an internal volume of .80ft^3 so that once the speaker is mounted in the enclosure I would have an internal volume of .69ft^3? Thanks, Dave Last edited by FaintReality at Sep 19 2002, 02:07 AM
lol man i really need to do some studying up on exactly what all these T/S specs mean..... i have a few down, but man