What is the difference between pink noise and white noise?

White noise has equal energy per Hz, so it sounds bright and hissy. Pink noise has equal energy per octave (-3 dB/octave slope), matching how our ears and RTAs analyze sound. Pink noise sounds balanced across all frequencies. Use pink noise for speaker testing and RTA measurements. Use white noise for testing electronics and digital systems.

Why is pink noise used for sound system equalization?

Pink noise has equal energy in each octave band, which matches how real-time analyzers (RTAs) display frequency content. When pink noise produces a flat RTA response, the system has uniform energy distribution across all octave bands. White noise would show a rising response on an RTA because higher octaves contain more Hz.

What is a log sine sweep and when should I use it?

A log sine sweep (Farina method) plays a tone that rises exponentially from a low frequency to a high frequency over a set duration. It is used for impulse response measurements because it provides excellent signal-to-noise ratio and separates harmonic distortion from the linear response. Use sweeps for RT60, STI, and detailed room analysis.

What is MLS and when is it better than a sweep?

MLS (Maximum Length Sequence) is a pseudo-random binary signal used for impulse response measurement. Its advantage over sweeps is that it sounds like noise, making it less disruptive in occupied spaces. Its disadvantage is lower immunity to time-variance (moving people, changing HVAC). Use MLS when a sweep would be too conspicuous.

What is brown noise and what is it used for?

Brown noise (also called Brownian or red noise) has a -6 dB/octave slope, meaning even more low-frequency emphasis than pink noise. It sounds like a deep rumble. It is used for testing subwoofer response, masking low-frequency environmental noise, and simulating traffic noise in environmental acoustics studies.

How loud should I play pink noise for system testing?

For RTA measurements, play pink noise at a level 10-15 dB above the ambient noise floor. In a typical venue with 40 dBA ambient noise, target 55-60 dBA at the measurement position. For transfer function measurements, the reference signal level matters less because coherence indicates measurement quality regardless of absolute level.

Can I use the noise generator for speaker burn-in?

Yes. Pink noise at moderate levels (75-85 dBA) is commonly used for speaker burn-in and break-in. The equal energy per octave exercises all frequency ranges uniformly. SonaVyx can generate continuous pink noise for extended periods. Most manufacturers recommend 24-48 hours of pink noise for new speaker break-in.

Is the generated noise truly random?

SonaVyx uses the WebAudio API random number generator for noise signals and deterministic algorithms for sweeps and MLS. The noise is pseudo-random with sufficient randomness for all audio measurement applications. MLS sequences are deterministic by design, using verified primitive polynomials for maximal-length LFSR generation.

What is the difference between pink noise and white noise?

White noise has equal energy per Hz, so it sounds bright and hissy. Pink noise has equal energy per octave (-3 dB/octave slope), matching how our ears and RTAs analyze sound. Pink noise sounds balanced across all frequencies. Use pink noise for speaker testing and RTA measurements. Use white noise for testing electronics and digital systems.

Why is pink noise used for sound system equalization?

Pink noise has equal energy in each octave band, which matches how real-time analyzers (RTAs) display frequency content. When pink noise produces a flat RTA response, the system has uniform energy distribution across all octave bands. White noise would show a rising response on an RTA because higher octaves contain more Hz.

What is a log sine sweep and when should I use it?

A log sine sweep (Farina method) plays a tone that rises exponentially from a low frequency to a high frequency over a set duration. It is used for impulse response measurements because it provides excellent signal-to-noise ratio and separates harmonic distortion from the linear response. Use sweeps for RT60, STI, and detailed room analysis.

What is MLS and when is it better than a sweep?

MLS (Maximum Length Sequence) is a pseudo-random binary signal used for impulse response measurement. Its advantage over sweeps is that it sounds like noise, making it less disruptive in occupied spaces. Its disadvantage is lower immunity to time-variance (moving people, changing HVAC). Use MLS when a sweep would be too conspicuous.

What is brown noise and what is it used for?

Brown noise (also called Brownian or red noise) has a -6 dB/octave slope, meaning even more low-frequency emphasis than pink noise. It sounds like a deep rumble. It is used for testing subwoofer response, masking low-frequency environmental noise, and simulating traffic noise in environmental acoustics studies.

How loud should I play pink noise for system testing?

For RTA measurements, play pink noise at a level 10-15 dB above the ambient noise floor. In a typical venue with 40 dBA ambient noise, target 55-60 dBA at the measurement position. For transfer function measurements, the reference signal level matters less because coherence indicates measurement quality regardless of absolute level.

Can I use the noise generator for speaker burn-in?

Yes. Pink noise at moderate levels (75-85 dBA) is commonly used for speaker burn-in and break-in. The equal energy per octave exercises all frequency ranges uniformly. SonaVyx can generate continuous pink noise for extended periods. Most manufacturers recommend 24-48 hours of pink noise for new speaker break-in.

Is the generated noise truly random?

SonaVyx uses the WebAudio API random number generator for noise signals and deterministic algorithms for sweeps and MLS. The noise is pseudo-random with sufficient randomness for all audio measurement applications. MLS sequences are deterministic by design, using verified primitive polynomials for maximal-length LFSR generation.

Pink Noise Generator Online

Pink noise is a broadband test signal with equal energy per octave, making it the standard reference for sound system equalization and RTA measurements. SonaVyx generates calibrated pink noise, white noise, brown noise, log sine sweeps, and MLS (Maximum Length Sequence) signals directly in your browser using the WebAudio API, with configurable level, bandwidth, and duration for professional audio testing.

Try It Now

Open the noise generator — pink noise, sweeps, and MLS test signals in your browser.

Open Tool

Technical Specifications

Parameter	Value	Standard
Signal Types	Pink, white, brown, sine sweep, MLS	AES-2id compliant
Sample Rate	44.1 / 48 kHz	Device native rate
Bit Depth	32-bit float (WebAudio)	IEEE 754
Pink Noise Spectrum	-3 dB/octave slope	Equal energy per octave
Sweep Range	20 Hz - 20 kHz (configurable)	Log sweep (Farina method)
MLS Orders	2 - 18 (131071 samples max)	LFSR-based generation
Level Control	-60 to 0 dBFS	Digital level
Output	Speaker / headphone / loopback	WebAudio destination

How to Use the Noise Generator

Select Signal Type

Choose pink noise for RTA and system EQ work, white noise for electronics testing, sine sweep for impulse response measurements, or MLS for environments where sweep artifacts are problematic. Each signal type has specific applications in audio measurement.

Set Level and Duration

Adjust the output level to a safe starting point (start at -20 dBFS). For continuous measurements, select continuous mode. For timed measurements, set the duration. For sweeps, choose the sweep length (2-20 seconds) — longer sweeps provide better signal-to-noise ratio.

Route to Your System

Play the test signal through your sound system by selecting the appropriate audio output. For loopback measurements, SonaVyx can route the generator signal internally to the reference channel while simultaneously outputting to the speakers.

Measure with RTA or Transfer Function

While the generator runs, switch to RTA mode to view the system frequency response, or use transfer function mode for magnitude, phase, and coherence measurements. SonaVyx correlates the known generator signal with the measured microphone signal for accurate analysis.

Understanding Test Signals for Audio

Test signals are the foundation of audio measurement. Each signal type has specific characteristics that make it suitable for different measurement tasks. The choice of test signal affects measurement accuracy, speed, signal-to-noise ratio, and the ability to reject interference from ambient noise or time-variant conditions.

Pink Noise: The RTA Standard

Pink noise has a power spectral density inversely proportional to frequency (1/f), producing a -3 dB/octave slope on an FFT analyzer. When viewed on an RTA with octave or fractional-octave band analysis, pink noise appears flat because each band integrates energy over a frequency range proportional to its center frequency. This makes pink noise the natural companion to RTA measurements for system equalization.

Logarithmic Sine Sweep: Maximum SNR

The log sine sweep, described by Angelo Farina in 2000, concentrates all test energy at one frequency at a time, producing the highest possible signal-to-noise ratio. A 10-second sweep typically achieves 30-40 dB better SNR than pink noise. The sweep also separates harmonic distortion components in the impulse response, allowing linear and nonlinear analysis from a single measurement.

MLS: Noise-Like Alternative

Maximum Length Sequences are deterministic binary signals that have noise-like spectral characteristics. Their primary advantage is that they sound like broadband noise, making them less intrusive than sweeps in occupied spaces such as theaters or churches during rehearsal. However, MLS measurements are sensitive to time-varying conditions and do not separate nonlinear distortion from the linear impulse response.

Noise Generator Comparison

Feature	SonaVyx	Smaart v9	REW	OSM
Pink noise generation	Yes (WebAudio)	Yes (built-in)	Yes (generator)	No (external)
Log sine sweep	Yes (Farina)	No (external)	Yes	No
MLS signal	Yes (order 2-18)	No	Yes	No
Brown noise	Yes	No	No	No
Browser-based	Yes	No	No	No
Internal loopback	Yes	Via ASIO	Via ASIO	Via OS
Price	Free	$898	Free	Free

Frequently Asked Questions

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Pink Noise (Glossary)

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Standards References

AES-2id:2023 — AES information document for room impulse response measurement (excitation signals)
IEC 60268-1:1985 — Sound system equipment: General (test signal specifications)
ISO 3382-1:2009 — Room acoustics: Reverberation time (excitation signal requirements)
IEC 61672-1:2013 — Sound level meters: Specifications (noise signal verification)