Audio speaker repair is a task that will eventually befall every audiophile or musician. Blown speakers, accidental and environmental damage, are a regular part of life for delicate speaker components, but there are several repair options. Some can be taken on with a bit of mechanical skill, but more serious repairs should be entrusted to professionals specializing in more advanced speaker work.
Why Speakers Fail
Aside from accidental and environmental damage, the main reason speakers fail, or "blow" as it is commonly known, is failure of the internal voice coil. Voice coil failures occur when an amplifier produces too much power for the speaker to handle, or the amplifier malfunctions in some way. In both cases, excess voltage has reached the voice coil, causing it to burn out.
Speaker and Amplifier Matching
Speaker handling capacity is measured in fixed wattage and ohm ratings. Typical ohm ratings for speakers is either 4, 8, or 16 ohms, with wattage ratings anywhere from single digits to several hundred or more. It is important to note that speaker manufacturers may assign several wattage ratings, including RMS, peak, and continuous. RMS stands for "root means square" and is the most reliable and realistic power handling measurement, followed by continuous wattage. Peak power handling is the speaker's ability to handle increased wattage for short periods of time, and should not be used as a guideline for use.
Amplifier power output is measured in various wattages and ohm ratings, in order to accommodate speakers of different ohm ratings. Wattage increases as ohm loads decrease, meaning that an amplifier rated at 300 watts at 8 ohms, will produce somewhere in the area of 450+ watts (50 percent or more), when a 4 ohm speaker is attached. Speaker and amplifier ratings must always be investigated before pairing components.
Repairing Blown Speakers
Blown speakers, especially vintage or high-end units, can be repaired by re-coning. A job best left to professionals, re-coning involves the removal and replacement of all speaker parts except the magnet and basket structure.
Replacement of blown speakers is sometimes an easier, and more cost-effective option, and one that can be undertaken by anyone with a bit of mechanical skill. Replacing a speaker involves removal of the old unit, and popping in a new one- a matter of removing four screws and reconnecting two wires. If exact replacements cannot be found, it is usually best to replace speakers in pairs or sets, to avoid uneven sonic output. Be sure to purchase speakers with wattage and ohm ratings that are compatible with your amplifier.
Repairing Tears and Holes
Small tears and holes in the diaphragm or speaker surround are easily repaired with a dab of silicone sealer, which has been aloud to cure and set properly. Large tears and holes will require a re-cone, or speaker replacement.
Tags: wattage ratings, accidental environmental, accidental environmental damage, environmental damage, involves removal, mechanical skill, power handling
