Dead, Blown or Miswired: Diagnosing a Silent Speaker
A speaker goes quiet and the diagnosis people reach for first is also the most expensive one: a dead, irreplaceable driver, headed for the bin. Sometimes that is exactly right. Just as often the driver itself is completely healthy and the fault is a loose connector, a balance control nudged to one side months ago, or a torn cone that buzzes under a real song instead of staying silent the way a genuinely dead speaker would. The three failures — dead, blown and miswired — can sound similar enough from the listening chair that guessing wrong means buying a replacement for a fault a five-minute cable swap would have found.
Three faults, one symptom
"No sound from that speaker" covers three different failures, and they call for different fixes. A dead driver has an open circuit somewhere between the amplifier and the voice coil — a snapped internal lead, a corroded connector, or a coil that has genuinely burned through — so no signal reaches the cone at all. A blown driver is receiving the signal and trying to move; something in its moving assembly is damaged, most often a torn cone or surround, or a voice coil that has rubbed against the magnet gap after physical or thermal damage. A miswired speaker is completely healthy on both counts — it is receiving a clean signal and its coil is intact — but something upstream makes it sound wrong or absent anyway: reversed polarity, swapped channels, a balance control, or a mono toggle left on. Only one of the three is actually broken hardware.
What isolates the driver from the wiring: swap it
Before opening a cabinet or reaching for a meter, move the problem instead of guessing at it. Take the cable feeding the silent speaker and connect it to a channel or output you know is working, or take a speaker you know is good and connect it to the suspect channel. If the fault follows the speaker to the new channel, the driver is at fault — dead or blown. If the channel stays silent with a known-good speaker attached, the cause is upstream: the cable, the connector, the amplifier output, or a control set to mute that side. This single swap sorts "driver problem" from "everything else" before you touch a screwdriver, and it costs nothing but a few minutes.
The one instrument that actually helps: a multimeter and DC resistance
A cable swap tells you whether the fault travels with the driver. A multimeter tells you whether the driver itself is open. Set a multimeter to resistance, disconnect the speaker from the amplifier, and touch the probes to its two terminals. What you read tells you which of the three faults you are looking at, and it is a low-current reading from the meter's own internal battery — nowhere near enough current to move the cone the way a direct battery connection would, which is why this check is safe on any driver, tweeters included, unlike a deliberate DC jolt. This applies to a conventional dynamic driver — the voice-coil-and-magnet design behind most laptop, phone, desktop and headphone drivers — and the numbers below are two manufacturers' own figures for that design.
| Multimeter reading | What it means |
|---|---|
| On a guitar or pro-audio cone driver, below the rated impedance but not by much — roughly 5-8 Ω on an 8 Ω driver, about double that on a 16 Ω one, per Celestion's own figures for its speakers | Healthy, for that product line. If the speaker is still silent, the fault is upstream, not in the driver. |
| On a car-audio cone driver, a DC resistance clearly under the rated figure — a 4 Ω-rated driver commonly reads about 3.4 Ω, per Kicker's own technical paper | Also healthy: different manufacturer, different market, same shape — rated impedance is an AC figure and DC resistance reads lower. Not a fault on its own. |
| Infinite, or "OL" on the display | An open circuit. The coil's own circuit is broken — a snapped internal lead or a burned-out winding. This is a dead driver. |
| Roughly normal resistance, but the speaker distorts or won't move cleanly by hand | The coil circuit is intact; the fault is mechanical. This is a blown driver, not a dead one. |
Neither manufacturer measured a laptop, phone or earbud driver, so take the exact ohm figures above as what a conventional dynamic cone driver does, not a universal number — a planar-magnetic or balanced-armature driver, common in higher-end IEMs, is built on a different principle and will not sit in these ranges at all. What does carry across every driver design is the shape of the two real faults: a reading near zero ohms, or one that pegs at infinite or "OL", means a shorted or broken coil regardless of the driver's rated impedance.
Celestion's own troubleshooting guidance for its drivers adds a second, no-meter-needed check: a healthy cone "should move freely for a few millimetres" when pressed gently by hand, springing back to centre with no scraping or grinding sound. A grinding or scraping sensation as the cone moves is the coil rubbing against the magnet gap — a mechanical fault a resistance reading alone will not always catch, since a rubbing coil can still read close to normal until it shorts.
What a blown driver actually sounds like
True, total silence at every volume and every frequency is far more often a dead driver or a dead channel than a blown one. A blown driver has usually not stopped moving; it has stopped moving correctly, and a damaged mover rarely stays quiet. Celestion's own repair notes describe a torn cone as something that "will lead to rapid failure" and that shows up first as buzzing rather than silence — a small tear rattling against itself on certain notes, loudest exactly where the cone excursion is greatest. A voice coil that has started rubbing produces a scratching or grinding texture layered on top of the intended sound, again worst at the frequencies and volumes that move the cone furthest. If a speaker plays cleanly at low volume and only distorts, buzzes or crackles as you push it louder, that is the signature of a blown driver, not a dead one.
This site's own left/right speaker test is built for exactly this comparison: it plays the same steady tone into one channel at a time, so you can listen for a clean tone, a distorted one, or nothing at all with the source held constant — removing the variable a piece of music introduces, where panning and mix choices make one side sound different from the other even when both speakers are fine.
Ruling out miswiring before you blame the hardware
A speaker that is neither dead nor blown can still seem broken. Software and settings are the fastest thing to check and the easiest to forget: a left/right balance control nudged off-centre quietly favours one side until someone finds it again, and a "mono audio" accessibility toggle — present in both Windows and macOS — folds both channels down to identical content, which can make a real channel fault invisible or an imaginary one appear. Reversed polarity is a wiring fault rather than a setting: connect a speaker's leads backwards relative to its pair, and instead of silence you get a specific, recognisable sound — a thin, hollow image with no solid centre, because the two speakers are now pushing air in opposite directions on the same signal instead of together. None of this shows up on a resistance meter, because nothing about the driver is actually damaged.
Putting it together
Start with the cable swap: it separates the driver from everything else in under a minute. If the fault stays with the speaker, a multimeter across its terminals tells you dead (open circuit) from blown (normal resistance, damaged movement) in one reading, and a gentle press on the cone catches the rubbing-coil case a meter alone can miss. If the driver reads clean and moves cleanly, look upstream — balance controls, a mono toggle, or reversed leads — before assuming anything is broken at all. If it is only one side of a pair of earbuds or headphones rather than a room speaker, why is one earbud quieter covers a narrower, more common version of this same question. And once you have confirmed a speaker's driver is genuinely healthy, speaker placement and room acoustics covers how a speaker that measures fine can still sound weak or hollow simply because of where it sits in the room.
The resistance ranges above come from Celestion's own troubleshooting guidance for its guitar and pro-audio speakers, and from a Kicker (Stillwater Designs) technical paper on its car-audio drivers; both are linked at the figure they support and scoped to the product each one measured.