I am planning to make a speaker enclosure with a vent. It appears that the length and diameter of the vent varies widely across different calculators. And WinISD seems to suggest that having a port any size will have the same effects, which is probably a feature of the free version. Is it reasonable to use the Butterworth B4 Ported results, given the smaller volume of the enclosure required? It is of course needs the adjustment for the volume occupied by the vent.
Code:
Ported Box
Vas = 1.88 lts
fs = 105 Hz
Qts = 0.59
D = 75 mm
Dimensions
Vb = 0.23 ft3 = 6.59 lts
= L x W x H
f3 = 60.46 Hz
fb = 105 Hz
Dv = 1 in = 2.5 cm
Lv = 0.02 in = 0.02 cm
Vb: Speaker Box Internal Volume
f3: 3dB Cutoff Frequency
fb: Enclosure Resonant Frequency
Dv: Port Diameter
Lv: Port Length
Note: Port volume (inside the port) does not count toward speaker volume.
Code:
Butterworth B4 Ported
Vas = 1.88 lts
fs = 105 Hz
Qts = 0.59
D = 75 mm
Dimensions
Vb = 0.13 ft3 = 3.76 lts
= L x W x H
f3 = 72.04 Hz
fb = 105 Hz
Dv = 1 in = 2.5 cm
Lv = 0.7 in = 1.7 cm
Vb: Speaker Box Internal Volume
f3: 3dB Cutoff Frequency
fb: Enclosure Resonant Frequency
Dv: Port Diameter
Lv: Port Length
Note: Port volume (inside the port) does not count toward speaker volume.
port diameter and lenght should be adjusted in winISD so the velocity is low enough (below 17) to avoid coughing. That is why you can adjust it. If the port diameter is to small, the air pushed trough it will make noises you don't want, so making it bigger (or use more than one port of the same lenght) can bring that air velocity down.
Thanks. I looked at the chart. It appears that it only slightly 17m/s at around 65.59 Hz (17.3m/s to be exact). Would this be a concern? I suppose then I can take the measure of 2.5 inches in diameter and 2.41 inches as length as my vent?
"the measure of 2.5 inches in diameter and 2.41 inches as length as my vent"
Those numbers are not showing in the information you posted B4 box is 1 inch port X .7 inch length? Where did those numbers come from?
Those numbers are not showing in the information you posted B4 box is 1 inch port X .7 inch length? Where did those numbers come from?
Hi - Just wondering if I am doing it correctly?
Driver
https://i.ibb.co/S76r0D9/SPL.jpg
https://i.ibb.co/RNqnXfg/Air-Velocity.jpg
Driver
https://i.ibb.co/S76r0D9/SPL.jpg
https://i.ibb.co/RNqnXfg/Air-Velocity.jpg
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