How to Replace a PA or DJ Speaker Driver (10", 12", 15", 18")
A blown woofer does not mean you need a new cabinet. Replacing the driver is usually a 20-minute job with a screwdriver and a multimeter, as long as the new driver matches the old one in size, impedance and power. This guide walks through it.
1. Confirm the driver is actually blown
Unplug the cabinet from the amplifier first.
Remove the grille and the driver's mounting screws, lift the driver and disconnect its wires.
Measure across the terminals with a multimeter on the ohms setting. An 8-ohm driver typically reads about 5.5–7 ohms DC. An open circuit (no reading) means the voice coil is burned.
Push the cone gently with both hands. Scraping, rubbing or a cone that will not move means a damaged voice coil. A torn surround or spider is also a reason to replace.
If the driver tests fine, check the cable, the crossover and the amplifier before buying anything.
2. Measure the old driver
Measurement
Why it matters
Nominal size (10", 12", 15", 18")
Must match the cabinet cutout.
Bolt-hole circle and hole count
Lets you reuse the existing holes or T-nuts.
Mounting depth
The new magnet must clear the back panel and any bracing.
Impedance (ohms)
Keeps the load on your amplifier safe.
RMS power
Should be equal to or higher than the old driver's RMS rating.
3. Match impedance and power the right way
Use the same impedance as the original. Putting a 4-ohm driver where an 8-ohm one was can overload the amplifier, and a 16-ohm driver will play noticeably quieter. In a cabinet with two or more drivers wired together, every replacement must match, or the total load changes (see our impedance and wiring guide).
Compare RMS (continuous) power, not peak or "max" figures. Peak numbers on spec sheets are short bursts and are not useful for matching an amplifier.
4. Full-range, woofer or guitar speaker?
PA/DJ full-range or woofer drivers are built for low frequencies and high excursion, usually used with a horn on top for the highs.
Guitar speakers are voiced for guitar amps and roll off the highs on purpose. Use a guitar speaker in a guitar cabinet and a PA driver in a PA cabinet.
If the cabinet has a horn, use a crossover so the compression driver never sees bass (see choosing a PA horn and driver).
5. Install and test
Connect + to + and – to – (the red or marked terminal is positive). Reversed polarity on one driver in a multi-driver cabinet cancels bass.
Seat the gasket so the frame seals against the baffle; air leaks cause whistling and weak bass.
Tighten screws evenly in a star pattern, snug but not so tight that the frame warps.
Play music at low volume, listen for rattles, then raise the level gradually.
Replacement drivers we carry
All are 5 Core drivers, shipped free to the lower 48 states and DC. Check each product page for full specifications before you order.