How to improve bookshelf loudspeaker sound

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 My audience on my youtube channel asked me how to find a crossover network capacitance and inductance so I will make it here


The speaker I made crossover network is a microlab b77. The speaker lacked the woofer's crossover network, no absorbent so I fixed it for cleaner sound and changed the tweeter's high pass filter to a better one.

Step 1

Change the old capacitor to a metalized polypropylene capacitor (very clean sound). The capacitor value is 4 uf and the speaker is 8 ohms so the crossover frequency =1/6.28x8x4 = 0.004976 x 1,000,000 = 4976 Hz (x1,000,000 come from Farad to microfarad)

If you want to find crossover frequency C= 0.1590/(R x F) x 1,000,000 for uf


Step 2

Find induction for the woofer.

L = .1592 x 4(woofer resistance)/4976(Hz) =1270 micro Henry x1000 = 0.127 mH but I has 0.1 mH so the crossover point may change a little but not much. If you want the complete sound you may find 0.127 mH

Speaker crossover diagram.


Step3

Add absorbent to the speaker cabinet.

The absorbent lower standing wave in the speaker cabinet. It also improves bass response.


See the sound test video here.



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