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Alright, so I am in the process of making a passive subwoofer, using two TB W5-1138sm drivers. I have never before made a low pass filter, let alone designed one, but I was curious if somebody could help me design/build a 350hz low pass filter.
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1.) Break in driver
2.) Measure T/S parameters -OR- use factory spec, which is not ideal
3.) Model in Unibox
4.) Export the Freq. and Impedance plots
5.) Import into Passive Crossover Designer
6.) Start modeling a textbook 2nd electrical filter @ 350-Hz
7.) You may have to flatten the impedance curve to get the filter to work correctly.
Here is my exercise, it was harder then I though it was going to be. Also, I haven't updated the thread yet, but I am a little disappointed with my passive sub. There is a sensitivity difference between my main computer speakers and the passive sub.
A small plate amp will solve all of these issues.
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You can either use PCD to determine the textbook values (only as starting points, the textbook values will probably not work) or you can use this website, use only the values from the woofer section. Keep in mind, the resistance is the resistance at 350 Hz, which Unibox will tell you.
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THANK YOU! I'm sorry it took so long to reply. i had to find another version of Excel to install....oh well. I followed your direction, after a couple of hours of wrapping my head around everything, I ordered the parts needed. Thanks for your help again!Comment
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Quick question. I had to get multiple caps of different sizes, do I run them in series, or in parallel with each other?Comment
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Typically parallel. Just add the individual values to get the final value.Comment
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Thank you a bunch. I read your subwoofer thread; that thing is insane. I find it incredible that it has more output subsonic than mine has peak.Comment
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