Narrower noise bands produce single centre pitch rather than edge pitches

Evidence

However, at a centre frequency of 3 kHz, pitch matches no longer occur at the spectral edges but are distributed throughout the pass band. This tendency is more often seen with a bandwidth of 200 Hz, as displayed in Fig. 5.15c. Only at the 300-Hz centre frequency do two pitches corresponding to the spectral edges show up. With increasing centre frequency, however, the pitches correspond more and more to the centre of the noise band. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 743