What happens if one speaker has reversed polarity?

When one speaker is reversed relative to another, they cancel at frequencies where their coverage overlaps. At the crossover frequency, cancellation can exceed 30 dB. Low frequencies are most affected because they are omnidirectional. The stereo image collapses, bass disappears at center seating, and the system sounds thin and hollow.

How does SonaVyx detect reversed polarity?

SonaVyx computes the cross-correlation between the electrical reference signal and the acoustic measurement. The sign of the correlation peak indicates polarity. A positive peak means the acoustic output matches the electrical input polarity (correct). A negative peak means the speaker cone moves in the opposite direction (reversed).

Can polarity be reversed inside a processor or amplifier?

Yes. Many digital processors, crossovers, and amplifiers have polarity invert switches. A signal can be inverted at any point in the chain: the mixer output, the processor crossover, the amplifier, or the speaker cable. Only one inversion in the chain is needed to reverse polarity. SonaVyx detects the net result regardless of where the inversion occurs.

Is polarity the same as phase?

No. Polarity is a simple flip: the signal is either normal or inverted (180 degrees at all frequencies simultaneously). Phase is frequency-dependent: different frequencies can have different phase shifts. A polarity reversal shows as 180 degrees across all frequencies. Phase issues from time delays show as a frequency-dependent slope in the phase plot.

Should I check polarity before or after time alignment?

Always check polarity first. If polarity is reversed, time alignment will attempt to compensate for the resulting cancellation by adjusting delay, producing incorrect results. The correct sequence is: 1) verify polarity, 2) correct any reversals, 3) then perform time alignment using the delay finder.

How do I check polarity on a subwoofer?

Use the same cross-correlation method with pink noise. Position the microphone at the crossover region where the sub and main speaker coverage overlaps. Check the sub polarity against the main speaker. If reversed, toggle the sub polarity switch. Then verify by measuring both together: correct polarity produces a smooth transition through crossover.

Can I check polarity with music instead of pink noise?

Yes, if the music has sufficient broadband content. Dense mixes with bass, midrange, and high-frequency content work well. Isolated instruments or vocals may not provide enough bandwidth for reliable detection. Pink noise is preferred because it provides equal energy per octave, ensuring consistent results across the full frequency range.

What is absolute polarity and does it matter?

Absolute polarity means the speaker cone moves outward when a positive voltage is applied. Some audiophiles claim absolute polarity is audible on transient-heavy material. For live sound, relative polarity between speakers is far more important than absolute polarity. SonaVyx measures relative polarity against your reference signal.

What happens if one speaker has reversed polarity?

When one speaker is reversed relative to another, they cancel at frequencies where their coverage overlaps. At the crossover frequency, cancellation can exceed 30 dB. Low frequencies are most affected because they are omnidirectional. The stereo image collapses, bass disappears at center seating, and the system sounds thin and hollow.

How does SonaVyx detect reversed polarity?

SonaVyx computes the cross-correlation between the electrical reference signal and the acoustic measurement. The sign of the correlation peak indicates polarity. A positive peak means the acoustic output matches the electrical input polarity (correct). A negative peak means the speaker cone moves in the opposite direction (reversed).

Can polarity be reversed inside a processor or amplifier?

Yes. Many digital processors, crossovers, and amplifiers have polarity invert switches. A signal can be inverted at any point in the chain: the mixer output, the processor crossover, the amplifier, or the speaker cable. Only one inversion in the chain is needed to reverse polarity. SonaVyx detects the net result regardless of where the inversion occurs.

Is polarity the same as phase?

No. Polarity is a simple flip: the signal is either normal or inverted (180 degrees at all frequencies simultaneously). Phase is frequency-dependent: different frequencies can have different phase shifts. A polarity reversal shows as 180 degrees across all frequencies. Phase issues from time delays show as a frequency-dependent slope in the phase plot.

Should I check polarity before or after time alignment?

Always check polarity first. If polarity is reversed, time alignment will attempt to compensate for the resulting cancellation by adjusting delay, producing incorrect results. The correct sequence is: 1) verify polarity, 2) correct any reversals, 3) then perform time alignment using the delay finder.

How do I check polarity on a subwoofer?

Use the same cross-correlation method with pink noise. Position the microphone at the crossover region where the sub and main speaker coverage overlaps. Check the sub polarity against the main speaker. If reversed, toggle the sub polarity switch. Then verify by measuring both together: correct polarity produces a smooth transition through crossover.

Can I check polarity with music instead of pink noise?

Yes, if the music has sufficient broadband content. Dense mixes with bass, midrange, and high-frequency content work well. Isolated instruments or vocals may not provide enough bandwidth for reliable detection. Pink noise is preferred because it provides equal energy per octave, ensuring consistent results across the full frequency range.

What is absolute polarity and does it matter?

Absolute polarity means the speaker cone moves outward when a positive voltage is applied. Some audiophiles claim absolute polarity is audible on transient-heavy material. For live sound, relative polarity between speakers is far more important than absolute polarity. SonaVyx measures relative polarity against your reference signal.

Speaker Polarity Test & Checker

Speaker polarity indicates whether a loudspeaker cone moves outward (positive) or inward (negative) in response to a positive voltage. SonaVyx tests polarity using cross-correlation peak sign analysis per the transfer function measurement, returning a definitive +1 (correct) or -1 (reversed) result. Reversed polarity between speakers causes destructive interference and up to 30 dB of cancellation at crossover frequencies.

Try It Now

Open the polarity checker in transfer function mode — instant +1/-1 result.

Open Tool

Technical Specifications

Parameter	Value	Standard
Detection Method	Cross-correlation peak sign	Transfer function IR
Result	+1 (normal) or -1 (reversed)	Binary determination
Frequency Range	20 Hz - 20 kHz	Full bandwidth
Test Signal	Pink noise or impulse	Broadband required
Confidence Indicator	Coherence-based validation	AES-2id clause 6
Processing	Rust WASM (client-side)	Instant result

How to Test Speaker Polarity

Connect Reference Signal

Route the system output (pre-amplifier or processor output) as the reference channel. Connect your measurement microphone as the measurement channel. SonaVyx needs both signals to compute the cross-correlation.

Play Broadband Signal

Send pink noise or broadband music through the speaker under test. The signal must contain energy across a wide frequency range for reliable polarity detection. Avoid using sine tones or narrow-band signals.

Check the Result

SonaVyx computes the cross-correlation between the reference and measured signals. A positive peak indicates correct polarity (+1). A negative peak indicates reversed polarity (-1). The result appears within seconds of starting the measurement.

Verify and Correct

If polarity is reversed, check the speaker cable wiring (swap + and - at one end only), the amplifier polarity setting, or the processor polarity invert switch. Re-test after correction to confirm +1 polarity.

Understanding Speaker Polarity

Every loudspeaker has a defined positive and negative terminal. When a positive voltage is applied to the positive terminal, the cone should move outward. If the wiring is reversed at any point in the signal chain (mixer, processor, amplifier, or speaker cable), the cone moves inward instead. This reversal affects every frequency simultaneously, distinguishing polarity from phase.

Why Polarity Matters for Multi-Speaker Systems

In a single-speaker system, reversed polarity is rarely audible. In multi-speaker systems, polarity becomes critical. When two speakers are in opposite polarity, their outputs cancel at frequencies where coverage overlaps. At the crossover frequency between a subwoofer and main speaker, reversed polarity creates a deep null that no amount of EQ or delay adjustment can fix. The solution is always to correct the polarity first.

Common Causes of Reversed Polarity

The most common cause is miswired speaker cables, especially in permanent installations where cables are terminated on site. Digital processors often have per-output polarity switches that can be accidentally toggled. Some amplifier models invert polarity by design. And certain crossover topologies (like odd-order Butterworth) naturally invert one output. The only reliable way to verify is measurement.

Polarity in the Context of System Optimization

The standard system optimization workflow is: verify polarity, set delay alignment, adjust level matching, then apply EQ. Polarity must be the first check because all subsequent steps assume correct polarity. SonaVyx integrates polarity checking into the transfer function measurement mode, so you can verify polarity, check delay, and view the frequency response in a single measurement session.

Polarity Checker Comparison

Feature	SonaVyx	Smaart v9	REW	OSM
Polarity detection	Yes (auto)	Yes (IR visual)	Yes (IR visual)	Yes (IR)
Auto +1/-1 result	Yes	No (manual)	No (manual)	No (manual)
Coherence validation	Yes	Yes	Yes	Yes
Browser-based	Yes	No	No	No
Multi-speaker workflow	Guided	Manual	Manual	Manual
Price	Free	$898	Free	Free

Frequently Asked Questions

Related Tools & Resources

Delay Finder

Time-align speakers after polarity verification

Transfer Function

Full magnitude and phase measurement

Problem Detector

Automated polarity and phase problem detection

Polarity (Glossary)

Definition and technical explanation

Standards References

AES-2id:2023 — AES information document for room impulse response measurement (polarity from IR)
IEC 60268-5:2003 — Sound system equipment: Loudspeakers (polarity marking requirements)
AES-12id-2006 — AES information document for digital audio measurements: Signal polarity