TABLE I.
The range of frequencies of significant standing wave effects (≥ fλ/4) estimated based on average ear-canal (EC) lengths for different species (as summarized in Rosowski, 1994; Qi et al., 2006; Ravicz et al., 2007). These estimates are calculated assuming the ear canal is left intact and the OAE probe is sealed near the ear canal entrance.
| Species | EC length (mm) | Standing waves effects (kHz) |
|---|---|---|
| Human (adult) | 25–30 | ≥ 3.4–2.8 |
| Human (newborn) | 13–23 | ≥ 6.5–3.7 |
| Chinchilla | 30 | ≥ 2.8 |
| Cat | 15 | ≥ 5.6 |
| Ferret | 10–12 | ≥ 8.6–7.1 |
| Guinea pig | 9 | ≥ 9.5 |
| Gerbil | 4a | ≥ 21.3 |
| Mouse | 6 | ≥ 14.3 |
a
Length of the bony ear canal (i.e., excluding cartilaginous part).