TABLE 1.

Subjective responses in the post-experiment subjective test.

Response	None	Fm: formant modification						PFm: pitch + formant modification
	0	200	100	50	−50	−100	−200	100	50	25	−25	−50	−100
“none”	40	9	22	31	36	22	9	0	6	24	34	17	0
“pitch”	0	5	6	3	0	5	6	15	18	8	2	14	19
“timbre	0	12	11	6	3	7	11	0	6	7	4	4	2
“pitch + timbre”	0	14	1	0	1	6	14	25	10	1	0	5	19

The numbers represent the numbers of participants who perceived the altered auditory feedback (AF) as only F0-shifted, only formant-shifted, both F0- and formant-shifted, and absent altogether (did not identify any acoustical modification). “none”: participants who did not identify any acoustical modification; “pitch”: participants who perceived the altered AF as only F0-shifted; “timbre”: participants who perceived the altered AF as only formant-shifted; “pitch + timbre”: participants who perceived the altered AF as both F0- and formant-shifted.