PA Speakers and Powered Speaker Systems

Powered, passive or installed: how the speaker gets its power

A powered speaker has a built-in amplifier, so it needs only AC power and a signal. A passive speaker needs an external amplifier with matching power and impedance. Installed models include ceiling speakers, horn speakers for outdoors and IP speakers that join a network for paging and announcements. Match the type to the job: portable events favor powered boxes, while a fixed building system favors ceiling or horn speakers wired to a central amplifier.

Watts, driver size, coverage and replacement drivers

Prefer continuous (RMS) watts over peak figures, and note sensitivity in dB, since a more sensitive speaker plays louder from the same power. Driver size sets bass depth: a 12 or 15 inch woofer moves more air than a 6 inch one. A coverage angle, such as 130 degrees, tells you how widely the sound spreads. When replacing a woofer, match diameter, mounting pattern, impedance and power rating exactly, or it will not fit or may fail.

Questions about PA Speakers and Powered Speaker Systems

Should I buy active or passive PA speakers?

Active speakers are simpler: plug in and power up. Passive speakers let you choose the amplifier and suit fixed installs or custom rigs, but you must match power and impedance. For portable use, active speakers are the easier choice.

What is a 70 V or 100 V speaker?

It is a constant-voltage design for long speaker lines in buildings. Each speaker connects through a transformer with selectable power taps, so many can share one amplifier output. It needs a matching constant-voltage amplifier.

Why will a replacement woofer not fit my speaker?

Mounting hole pattern, cutout diameter, depth, impedance and power can all differ. A driver with different specifications also changes how the cabinet sounds. Compare the full specification sheet with the original before buying.