Frequency
1000 Hz
Right air
20 dB
Left air (masked)
55 dB
Air–bone gap L
30 dB
Speech sounds lost
4 of 24
Drag or arrow-key across the plot to move the frequency probe. Letters dim as they fall below the better ear.
Tessitura / Threshold
Case Study 07 · Pure-tone air & bone conduction
A single chart carries the whole story: two ears plotted against frequency and hearing level, the speech banana laid over them, and the exact letters that fall out of reach.
Frequency
1000 Hz
Right air
20 dB
Left air (masked)
55 dB
Air–bone gap L
30 dB
Speech sounds lost
4 of 24
Drag or arrow-key across the plot to move the frequency probe. Letters dim as they fall below the better ear.
Every value the symbols encode, in decibels hearing level. NR = no response at the audiometer limit.
| Transducer | 125 | 250 | 500 | 750 | 1k | 1.5k | 2k | 3k | 4k | 6k | 8k |
|---|
Each phoneme plotted at its dominant band and typical level at one metre. Struck-through entries fall below the better ear.
Recorded for reproducibility. Method and equipment as delivered in booth B.
| Item | Setting | Note |
|---|---|---|
| Method | Modified Hughson–Westlake | 5 dB up, 10 dB down |
| Transducer | Insert, ER-3A | Reduces crossover risk |
| Masking noise | Narrowband, 40–70 dB EM | Plateau method |
| Bone oscillator | Mastoid placement | Forehead re-check at 1k |
| Ambient | 18 dBA | Within ANSI S3.1 limits |