Frequency sweep
Before you start: Start at low device volume. A sweep can move through frequencies your device reproduces unevenly. Stop for discomfort or rattling and never boost volume to chase an inaudible frequency.
Frequency sweep controls
Run a logarithmic sine sweep between two chosen frequencies and record whether the path changes or drops out.
Loading audio controls.
Move continuously between two frequencies and record repeatable dropouts, abrupt changes or channel differences.
Interpretation: A repeated audible change can locate where in the selected digital range the complete playback path behaves differently.
Limit: An uncalibrated acoustic sweep cannot prove flat frequency response or identify which component created the change.
Safety and privacy: No sound starts automatically. Signals and analysis stay in your browser by default. Browser dBFS is not physical SPL.
How to use this test
- Choose a bounded range: Start with a moderate range and avoid raising device volume when an edge frequency is inaudible.
- Listen for repeatable changes: Note a dropout, buzz or abrupt level change only if it occurs at the same part of repeated sweeps.
- Change one path element: Repeat the identical sweep after one controlled cable, device or output change.
Choose the signal level: New references start at -40 dBFS peak. Select up to 0 in 5 dB steps, then press Play. This is WaveLocus's selectable range, not an industry standard or a physical-volume measurement. Zero is full-scale digital output; lower device volume before playback.
Reference and scope: REW documents -12 dBFS RMS within a measurement procedure that includes physical level-setting. That average-level convention differs from this page's peak control. It is not a universal listening recommendation. REW measurement-level procedure.
What is a frequency sweep test?
A frequency sweep test plays a tone that moves continuously from a selected starting frequency to an ending frequency. This tool uses a logarithmic sine sweep: the pitch changes while the source amplitude stays constant.
Use it to listen for changes across a range, rather than holding one pitch with the audio tone generator. An audible change is a listening observation, not a measured frequency-response curve.
How to interpret your frequency sweep results
The sweep changes smoothly: This is a listening observation, not proof of flat frequency response. Digital amplitude and perceived loudness are different.
You hear a dropout, abrupt change or rattle: Stop if uncomfortable. Repeat briefly with the same settings, then change one connection or output. A sweep cannot identify the faulty part by itself.
Source: REW level-setting procedure.
Frequently asked questions
What is a frequency sweep test used for?
It plays a changing reference between two selected frequencies. Record repeatable dropouts, buzzing or rattling, then change one setting or connection and repeat the same sweep.
Does a sweep measure frequency response?
Listening alone does not provide calibrated frequency response, hearing thresholds or a diagnosis of the faulty component. The room, playback path and listener all influence what is heard.
Can I adjust the channels while the sweep plays?
With Both selected, the independent left and right gains can be reduced during playback. Keep those gains unchanged when comparing repeated sweeps. Changing the route, range or duration stops the current playback.