Table 1.

Formant Fi and bandwidth Bi values, in hertz, of ‘reference’ stimuli /a/, /e/, /ə/, /ɤ/, /i/, /ɨ/, /ɯ/, /u/, /ʊ/, /ʉ/, /ʌ/, and /y/ synthesized for the perceptual experiment. F0=112Hz and duration is 600ms for all stimuli. Prototypical values are based on the monophthong oral vowels of the world’s languages, reported in UPSID (UCLA Phonological Segments Inventory Database, Maddieson, 1986).

Vowel	F1	F2	F3	F4	F5	B1	B2	B3	B4	B5
/i/	247	2062	3372	3896	4528	78	13	61	154	340
/y/	236	1756	2122	3410	4159	88	40	19	19	30
/ɨ/	252	1521	2139	3191	3898	103	24	20	20	28
/ʉ/	262	1257	1915	2906	3806	90	30	16	17	31
/ɯ/	296	1048	2119	3469	3984	80	18	16	19	19
/u/	258	705	2002	3175	3647	97	31	15	17	26
/ʊ/	340	1059	2069	3311	3932	67	18	16	20	21
/e/	364	1922	2509	3548	4154	48	40	148	67	145
/ /	376	1374	2012	3036	3866	57	26	21	21	40
/ɤ/	392	1062	2014	3192	3908	56	19	17	21	24
/ʌ/	546	1146	1998	3080	3627	39	55	31	31	120
/a/	734	1185	2241	3716	4169	38	45	55	137	118