Ive been learking around here for a month or so and ive been doing alot of reading. ive tryed to do the calculations myself and i think ive done ok but would some one go over them for me?
The sub im using is the vibe exact 8 inches.
T/S parameters from the vibe web site:
Qts: 0.475
Vas: 1.078 Ft3
fs: 37hz (sent about 5 emails to vibe to get this one.)
Xmax: 5mm
so my calculations are:
Vb: 1.909 Ft3
F3: 27.28 Hz
Fb: 30.37 Hz
Min port dia. 2.25 inches
port dia. hoping to use 2.5 inches
so vent length using 1 port will be 5.68 inches.
hope im right
many thanks
gav
You are porting this little sub. The box tuning (Fb) cannot be that much lower than the Fs of the sub. You have 37 Hz listed as Fs, so tune your enclosure so that the Fb hits at about that point, or just one or two Hz above or below it. You can go above it as much as you want, for example if you want to hit loud at 50 Hz (car freq.) tune your box there.
The Fs is the point of a speaker where it hits resonant frequency. This is considered the lowest Hz the speaker will play. This is not a problem if using a sealed box, but when porting it can be a problem if you have the box frequency (tuning freq. or Fb) too low. The speaker will over-excurt and be damaged.
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
No, not at all. But it might be about what you need to do for a 8" sub. Just try at around 40 Hz and see what it looks like, then at 50 Hz. Are you using a design program? If not, are you using a design calculator?
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.