Test pitches were limited to 100-3200 Hz for audibility

Evidence

Deviant intervals were always four semitones. Since standard pattern intervals were chosen from the set {1, 2, 3, 5, 6, 7 semitones}, depending on the condition (see Table 1 ), the difference between the standard and the deviant pitch interval was always 1, 2 or 3 semitones. The first tone of the first pattern always had a pitch of 450 Hz. To avoid the use of pitches which may not be clearly audible to everyone despite reporting normal hearing, all pitches were restricted to lie between 100 and 3200 Hz. — Dijk, Pim van, Physiology, Psychoacoustics and…, 5290