Brilliance Ratio
Calculate (T2000 + T4000) / (T500 + T1000) from caller-supplied reverberation times; interpretation remains project-specific.
Description
A brilliance ratio compares high-frequency reverberation times with mid-frequency times.
A brilliance ratio compares high-frequency reverberation times with mid-frequency times. It describes spectral decay balance rather than loudness.1
The returned values include Ratio. The How section below explains the calculation, input rules and interpretation.
When to use Brilliance Ratio
Use Brilliance Ratio when you need to evaluate the supplied records under the calculation and evidence rules below. No decay fitting, frequency interpolation or universal preferred ratio is provided.
Choose the measured quantities, units, weighting and measurement basis before entering values. For a reference, select the exact topic. For a catalog lookup, prepare complete source-backed records; for a screen, select an applicable caller limit.
How to use Brilliance Ratio and understand its results
- Choose the measured quantities, units, weighting and measurement basis before entering values. For a reference, select the exact topic. For a catalog lookup, prepare complete source-backed records; for a screen, select an applicable caller limit.
- Enter rt2000Seconds, rt4000Seconds, rt500Seconds, rt1000Seconds using the field table and calculation rules, then run the tool.
- Read ratio. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| rt2000Seconds | RT 2000 (s) | number; minimum: 0 | Required |
| rt4000Seconds | RT 4000 (s) | number; minimum: 0 | Required |
| rt500Seconds | RT 500 (s) | number; minimum: 0 | Required |
| rt1000Seconds | RT 1000 (s) | number; minimum: 0 | Required |
Enter finite strictly positive reverberation times at 2000, 4000, 500 and 1000 Hz. Divide the sums; if the direct result is nonfinite, scale all times by their maximum and retry. Require a positive finite result.
ratio=(T2000+T4000)/(T500+T1000) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| ratio | Ratio | number; minimum: 0 |
{
"input": {
"rt2000Seconds": 1.6,
"rt4000Seconds": 1.4,
"rt500Seconds": 1.8,
"rt1000Seconds": 1.7
},
"output": {
"ratio": 0.8571428571428571
}
}Limitations and assumptions
No decay fitting, frequency interpolation or universal preferred ratio is provided.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing fields without a declared default, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Bass Ratio: A bass ratio compares low-frequency reverberation times with mid-frequency times. It describes spectral decay balance rather than bass sound level. For a complementary task, use EDT and Late-Decay Reference: EDT is derived from the initial 0 to -10 dB decay slope and extrapolated to a 60 dB decay time; it emphasizes the early subjective decay. This reference explains the selected concept and the evidence needed to interpret it.
References
-
Brilliance Ratio — tool.io
Similar or alternative tools
- Bass Ratio
A bass ratio compares low-frequency reverberation times with mid-frequency times. It describes spectral decay balance rather than bass sound level.
- EDT and Late-Decay Reference
EDT is derived from the initial 0 to -10 dB decay slope and extrapolated to a 60 dB decay time; it emphasizes the early subjective decay. This reference explains the selected concept and the evidence needed to interpret it.