TABLE III.

Effects of Vowel Level on Maximum d’ for F2 Changes in Quiet.

Vowel Level	2nd Formant	High SR	Medium SR	Low SR
43 dB SPL	2000	3.99	4.84	5.65
	1900	3.22	3.91	5.07
	1800	1.89	2.27	4.64
	1750	0.97	1.17	2.61
	1725	0.52	0.70	0.25
	1710	0.40	0.55	0.25
63 dB SPL	2000	1.99	2.98	3.77
	1900	1.61	2.41	3.05
	1800	0.96	1.43	1.78
	1750	0.48	0.73	0.92
	1725	0.23	0.36	0.53
	1710	0.17	0.27	0.41
83 dB SPL	2000	1.08	1.77	3.09
	1900	0.88	1.44	2.50
	1800	0.52	0.85	1.47
	1750	0.26	0.43	0.75
	1725	0.12	0.20	0.40
	1710	0.09	0.15	0.31