i've changes input to 100 watts, but it's all the same
yep, looking at rear port, but front is also at 0!
I entered another driver, where the graph was visible. maybe this doesn't work with self entered drivers?
my main concers was that 8 mm was a bit small for a port > any comments on this?
yep, looking at rear port, but front is also at 0!
I entered another driver, where the graph was visible. maybe this doesn't work with self entered drivers?
my main concers was that 8 mm was a bit small for a port > any comments on this?
The standard answer is to keep it under 5% of the speed of sound - 17 meters/sec. You may be able to double this with flared ports.
This results in rather long ports in some circumstances. 1/4 the driver (frame) diameter seems to work with relatively low excursion drivers. For longer excursion drivers, you will want to use 1/3 to 1/2 of the frame diameter for best results.
This results in rather long ports in some circumstances. 1/4 the driver (frame) diameter seems to work with relatively low excursion drivers. For longer excursion drivers, you will want to use 1/3 to 1/2 of the frame diameter for best results.
7 m/s at 1watt? wow, that is a small port. I've had port noise using a 3" diameter piece of PVC with the edges sanded round at 20 m/s.
57 m/s is far too high. If you double the vent area, and double the length of the port, that will come down to 28.5m/s. Still too high unless you have some serious flares.
Have you checked the xmax graphs to see if this driver will actually move far enough to create an air velocity of 57 m/s? You may be suprised to find that you don't have 70 watts of power handling at low frequencies (especially with only 6mm of xmax).
Dan
57 m/s is far too high. If you double the vent area, and double the length of the port, that will come down to 28.5m/s. Still too high unless you have some serious flares.
Have you checked the xmax graphs to see if this driver will actually move far enough to create an air velocity of 57 m/s? You may be suprised to find that you don't have 70 watts of power handling at low frequencies (especially with only 6mm of xmax).
Dan
just did a simulation with the original design of the HATT III by Tony Gee.
using a 5 liter cabinet, the seas L12RCY/P and a vent of 3.36 cm by 13,8 cm long at 57 Hz
result by 1watt is 7,14 m/s and at 50 watts 50,4 m/s
when doing a rectangular port of 11,6 by 1 cm, I get 5,46 and 38,6 m/s
since the original design by Tony has been built several times, and because I'm getting "better" values, I presume I'm overlooking sth. Still a noob here!
using a 5 liter cabinet, the seas L12RCY/P and a vent of 3.36 cm by 13,8 cm long at 57 Hz
result by 1watt is 7,14 m/s and at 50 watts 50,4 m/s
when doing a rectangular port of 11,6 by 1 cm, I get 5,46 and 38,6 m/s
since the original design by Tony has been built several times, and because I'm getting "better" values, I presume I'm overlooking sth. Still a noob here!
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