Using pink noise for speaker level checks

Pink noise is a useful starting point for comparing speaker levels because each octave carries similar energy. That makes it more practical than a single sine frequency when the question is whether two speaker positions behave similarly across a broad range.

SignalProof can provide the repeatable noise source. Your external meter, or a meter app on a second device, provides the reading. SignalProof does not measure microphone audio.

Before you start

Use one playback device, one speaker route, and one meter for the complete comparison. Start at a conservative level. If the sound is uncomfortable, stop and lower the output before continuing.

Choose a quiet period and write down the background reading before playing pink noise. A changing air conditioner, open door, conversation, or moving microphone can make a small difference look more meaningful than it is.

What to keep consistent

• the phone or speaker playing the signal
• system volume
• distance from source to meter
• meter weighting and time setting
• room state, including open doors, windows, curtains, and people in the space

Changing any of these can change the result.

Speaker-to-speaker workflow

1. Select pink noise in SignalProof and choose the channel or speaker route you want to test.
2. Set a conservative dBFS level and keep the iPhone system volume fixed.
3. Put the meter at the listening position and keep its orientation unchanged.
4. Record the meter weighting and time setting.
5. Play the signal, allow the reading to settle, and write down the result.
6. Change only the speaker or channel being compared, then repeat from the same meter position.

If you move the phone, meter, furniture, or listening position between runs, record that change instead of treating the readings as a controlled comparison.

What to compare

For stereo speakers, compare the left and right channels at the same listening position. For a surround system, use its own speaker-routing controls or built-in test signals to isolate individual speakers; an iPhone stereo/Bluetooth route does not select center or rear speakers separately. The practical goal is usually consistency between readings, not proof of an absolute calibrated output level.

For a window or door comparison, play the same noise from the same position, then measure the other side before and after the change.

Copyable run sheet

Setting	Run A	Run B
Signal	Pink noise	Pink noise
SignalProof dBFS level	Record value	Same value
iPhone system volume	Record value	Same value
Output route or speaker	Record route	Record route
Source-to-meter distance	Record distance	Same distance
Meter weighting and time setting	Record settings	Same settings
Room state	Record doors, windows, HVAC, people	Record any change
Meter result	Record reading	Record reading

This sheet is intentionally a context record, not a calibration certificate. A useful comparison explains what stayed fixed and what changed.

How to interpret the difference

Start with repeatability. If repeating Run A produces noticeably different readings without an intentional setup change, investigate the room state, output route, volume, meter placement, and background noise before drawing a conclusion from Run B.

A consistent difference can support a practical adjustment, such as bringing two channels closer together. It does not prove the absolute accuracy of the phone, speaker, room, or meter.

What not to claim

Do not treat the result as a certified building acoustic rating, professional calibration certificate, or hearing safety diagnosis. SignalProof helps make the source repeatable so the measurement workflow has less guesswork.

Save and compare in SignalProof 1.1.0

Enter the readings from your separate meter and save a local session with the setup notes. Local readings and a single-session PDF are free. Lifetime Pro adds comparisons between meter records, CSV/PDF comparison exports, and reading-record tags.

Keep separate runs for the baseline and the changed setup. A difference is only interpretable when the signal, meter settings and conditions are documented. See why dBFS is different from an acoustic meter reading.