One-Decibel JND Reference

Return the nominal 1 dB level-difference reference with the psychophysical conditions required before it can be called a just-noticeable difference.

Description

A just-noticeable level difference depends on stimulus, listener and psychophysical method.

A just-noticeable level difference depends on stimulus, listener and psychophysical method. One dB is only a nominal reference increment.^[1]

Return the nominal 1 dB level-difference reference with the psychophysical conditions required before it can be called a just-noticeable difference.

When to use One-Decibel JND Reference

Use this tool to return the nominal 1 dB level-difference reference with the psychophysical conditions required before it can be called a just-noticeable difference.

Choose a supported reference topic, run an input-free reference with an empty object, or prepare the measured values and caller-supplied test records requested. Keep acoustic metrics, frequency, units and test conditions consistent.

How to use One-Decibel JND Reference and understand its results

Choose a supported reference topic, run an input-free reference with an empty object, or prepare the measured values and caller-supplied test records requested. Keep acoustic metrics, frequency, units and test conditions consistent.
Run the reference with an empty object {}. No input values or topic selection are required.
Read interpretation, nominalDifferenceDecibels, reference, requiredContext, universalJustNoticeableDifference. 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
(none)	Run the reference with an empty object {}.	No values required	Not applicable

Run with an empty object. Return fixed increment, interpretation, research reference and required-context list.

nominalDifference=1dB; universalJustNoticeableDifference=false

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
interpretation	Interpretation	string
nominalDifferenceDecibels	Nominal level difference (dB)	number
reference	Reference	string
requiredContext	Required JND context	list of string
universalJustNoticeableDifference	Universal JND	boolean

json

{
  "input": {},
  "output": {
    "interpretation": "A 1 dB difference is a reference increment, not a generally detectable or universally just-noticeable level difference.",
    "nominalDifferenceDecibels": 1,
    "reference": "Johnson et al., Journal of the Acoustical Society of America 93, 983-991 (1993), doi:10.1121/1.405404; Stillman et al., same volume, 425-434 (1993), doi:10.1121/1.405622.",
    "requiredContext": [
      "stimulus type, spectrum, and bandwidth",
      "frequency and presentation level relative to threshold",
      "masking and listening conditions",
      "listener population and hearing status",
      "psychophysical procedure and response criterion"
    ],
    "universalJustNoticeableDifference": false
  }
}

Limitations and assumptions

No audibility test, hearing diagnosis or generally detectable difference is established.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use Roughness 70 Hz Reference: Return the documented 70 Hz maximum of the 1-asp roughness reference while distinguishing that demonstration from a universal prediction. For a complementary task, use Speech SNR Screen: Calculate speech-to-noise level difference and compare it with an explicit caller-supplied minimum.

References

One-Decibel JND Reference — tool.io

Similar or alternative tools

Roughness 70 Hz Reference
Return the documented 70 Hz maximum of the 1-asp roughness reference while distinguishing that demonstration from a universal prediction.
Speech SNR Screen
Calculate speech-to-noise level difference and compare it with an explicit caller-supplied minimum.