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Showing posts from December, 2015

100W Subwoofer Amplifier Circuit

Subwoofer Amplifier Circuit DesignAudio Filter Design: Here we designed a Sallen Key low pass filter using OPAMP LM7332. The cut off frequency was assumed to be 200Hz and the Quality factor is assumed to be 0.707.  Also assuming the number of poles to be equal to 1 and value of C1 to be equal to 0.1uF, value of C2 can be calculated to be 0.1uF.  Assuming R1 and R2 to be same, the value can be found by substituting known values in the equation R1 = R2 = Q/(2*pi*fc*C2) This gives a value of 5.6K for each resistor. Here we select 6K resistors as R1 and R2. Since we want a closed loop gain filter, we do not require resistors at the non inverting terminal, which is shorted to the output terminal. Pre Amplifier Design: The preamplifier is based on class A operation of transistor 2N222A.  Since the required output power is 100W and load resistor is 4 Ohms, here we require a supply voltage of 30V.  Assuming the collector quiescent current to be 1mA and collector quiescent voltage to be half of supp…

How to match subwoofers and amplifiers

The secret to great bass is making sure your subwoofers and amp are evenly matched and will properly work together. And this article will help you figure out how to do just that — match amplifiers and subwoofers. We cover the important basics of power-matching, impedance, and planning for the number of subs you want, and we approach the situation from both sides of the system: Part A: You have the subs, which amp should you get?Part B: You have the amp, which subs should you get? Start with either part you want, but they're both worth a read. Part A
You have the subs, which amp should you get?The subs need to be the same
Multiple subs wired together must be the same coil type and impedance. If they’re not, the power won’t divide evenly between them, and some subs would probably be over-powered while others get under-powered. If you want to run different types of subs in a system, each type needs to have its own separate amp. Step 1: How much power? Find out the “watts RMS” rating of …