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What's the difference between active subwoofer and passive subwoofer?

An active subwoofer is powered by a built in amplifier. A passive subwoofer is powered by an external receiver or amp.

Google can be your friend.

An active subwoofer has it's own amplifier, either one built into the subwoofer cabinet, or an external one supplied with the purchase. A passive subwoofer requires a separate amplifier which you must purchase yourself.

EDIT: I hate guys with faster fingers than mine.

Here you go....


1) Passive and powered subwoofers
-PASSIVE SUBWOOFERS: Passive subs may be mono or stereo and contain no amplification. A mono passive subwoofer contains two woofers or a single woofer with a dual voice coil. A passive low pass filter feeds the woofer(s). Some passive subs contain a passive high-pass for output to the main speakers.

Considering a passive subwoofer? They can cost less and can be worthwhile if they are designed to be used with the speakers you already have. But it is difficult to adjust a passive sub's output or crossover without sonic problems. They will blend properly only with speakers they were designed to work with. Passive subs draw power from your system and bass requires a lot of power. Unless your amp/receiver has plenty of reserve power you might well run out of power when adding a passive sub. Consider passive subs only if;

A) They are offered as an option by the manufacturer of your main speakers.

B) You really know your stuff (or have competent help) and know that your Playwright Model 1901 speakers are similar enough to the Zoomtite Model Y that the Zoomtite Model SUB is designed to go with.

C) You just need to add some inexpensive bass punch to a pair of small speakers and you're not very picky. Powered subwoofers cost more, but offer far better value.

D) You have an extra amplifier and the ability to bi-amplify to the passive subs.

-POWERED SUBWOOFERS: Also referred to as active subwoofers. Powered subs have their own amplification and an active low-pass crossover to feed the woofer(s). Powered subs can also utilize various circuits for equalization, self-protection and distortion reduction. They may also have active or passive high-pass outputs. Powered subs can be adjusted to match your system. On a powered sub you can adjust the output level and crossover frequency to match a wide range of speakers. Powered subwoofers have their own amplification so instead of drawing power from your system they increase your total system power. By designing the amplifier, enclosure and driver (woofer) together, the manufacturer can optimize the performance of all three. As a result, powered subwoofers usually offer higher performance, smaller size, better value and greater reliability than passive subs.

o-k that's what I thought, I was looking at all the extra wiring you have to do on the passive sub- did not want to get into all that work.