A-Weighting Correction Lookup
Standardnominal A weightingtransfercorrectiondB fromactualpositivefrequency,not fullspectrumweightedLeq or calibratedinstrumenttolerance. Actual matched calibration,units,edition,geometry/measurement and model applicability independently established;not hearing/structural safety,compliance or universal perceptual prediction.
Description
A weighting applies a nominal frequency-dependent correction commonly used in sound-level reporting.
A weighting applies a nominal frequency-dependent correction commonly used in sound-level reporting.1
This calculator evaluates the declared curve at one positive frequency, without integrating a spectrum or establishing a calibrated instrument’s tolerance.
When to use A-Weighting Correction Lookup
Use this tool to apply the stated a-weighting correction lookup operation with an explicit input and unit basis.
How to use A-Weighting Correction Lookup and how it works
- Establish the measurement basis and units described above.
- Enter actualFrequencyHz and run the tool.
- Read result.value using the output meanings below.
- If input is rejected, correct the stated type, range, ordering or alignment issue and rerun; review successful results under the declared convention.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualFrequencyHz | Frequency Hz. Units, ordering and applicable branch are specified in the algorithm. | number | required; finite; strictly positive; further conditions in the algorithm |
Require positive frequency f in hertz. Evaluate the A transfer ratio with constants 20.6,107.7,737.9 and 12194 Hz, then return 20log10(ratio)+2 dB. Nonfinite arithmetic is rejected.
A(f) = 20log10(12194² f⁴/((f²+20.6²)(f²+12194²)sqrt((f²+107.7²)(f²+737.9²)))) + 2 dB Apply the declared units, ordering and branch conditions.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the declared output fields. | object |
| result.value | Nominal frequency-weighting correction in dB for one frequency. | number |
{
"input": {
"actualFrequencyHz": 100
},
"output": {
"result": {
"value": -19.144954291317546
}
}
}Limitations and assumptions
The output applies the declared operation to the values you supply. Establish the measurement basis, units, coefficients and any caller-selected rules before interpreting it. The tool does not independently collect or verify observations or decide whether a model or reference applies.
Supply explicit required fields with the documented types and dense aligned arrays. Unknown fields, wrong types and nonfinite numbers are rejected. Branch-specific constraints are explained above. A returned boolean, signed difference or tied result follows the stated convention; an input error instead means the required input contract was not satisfied. Very large inputs or outputs may be rejected by shared resource limits.
Alternative or Complementary methods
For a related operation, use C-Weighting Correction Lookup. C weighting describes a nominal frequency-dependent adjustment to sound levels.
For a related operation, use Measurement Time Weighting Lookup. Sound-level meter time weighting smooths a changing squared-pressure signal over a nominal response time.
References
-
A-Weighting Correction Lookup — tool.io
Similar or alternative tools
- C-Weighting Correction Lookup
C weighting describes a nominal frequency-dependent adjustment to sound levels.
- Measurement Time Weighting Lookup
Sound-level meter time weighting smooths a changing squared-pressure signal over a nominal response time.