To some a speaker is “just a speaker”, but for others, a speaker has a truly integral part to play in their audio set-up. All speakers fall into one of two categories, Active or Passive. What's the difference? Which one do you need?
An Active Speaker has an amplifier and electronic crossover (circuits that direct the incoming audio signals toward the drivers. High frequencies are sent to the “tweeter” and low frequencies are sent to the “woofer”.) built into the enclosure. The built-in amplifier is fed by a low level signal from the AV controller (pre-amplifier) which in turn drives the speaker from inside the box. An active speaker has many more inputs than a passive model, and allows you to connect your device or instrument directly into it to produce sound. The active speaker is still required to be powered, so you will need to have a power point handy also.
rear of an active speaker
A Passive Speaker does not have an amplifier built in to the enclosure, and needs to be connected with normal speaker wire to an external receiver/amplifier to drive the speakers and hear the audio. All you will find at the rear of the speaker are the inputs for your RCA audio cables. Below is a typical Home Theatre scenario.
rear of passive speaker
The decision to use an active or a passive speaker, as with many decisions in audio set ups is subjective and quite a personal one. The function of your speakers will contribute to your decision. If you need to have a mobile set up, you might choose an active speaker. This means you need only plug into the speaker from your mixer, laptop, instrument or other device, without needing to cable up an external amplifier. You can have less gear to transport using an active speaker set up.
Because an active speaker has an amplifier built in, they are quite popular with those who need to move their set up from place to place. You can just hook it up to your instrument, plug in the speaker and go. It’s a great portable set up option if you’re a DJ, spruiker or similar. One of the downsides to lugging around a set of active speakers is that they tend to be a bit heavier than passive speakers due to all the additional components internally. Still, it may be better than transporting an external amplifier and the various extra cables you may need to get your set-up going.
Passive speakers tend to be popular for more permanent scenarios such as home theatre / Hi-Fi Surround Sound set ups. This option tends to be more flexible when numerous speakers form part of the set-up. Each component is customisable, as you can choose what to pair your speakers with. You can choose the model of amplifier, front speakers, centre speaker, rears and subwoofer that suit your preferences.
Subwoofers
The majority of subwoofers are active speakers. Connected to a line-out from an external receiver, the low bass notes are amplified by the subwoofer itself. The difference between a subwoofer and other active speakers is that a subwoofer is made especially for low bass notes and is not suitable as a stand-alone active speaker. They cannot reproduce the higher frequencies other active speakers can.
