Appendix A
Background characteristics of participants.
Subject #	Age of ID	Age Aided	Study Entry Age	Number of longitudinal samples	Circuit	Gender	Program
	(mos)	(mos)	(mos)		(L/R)
S1	37	38	38	9	WDRC	female	Private oral
S2	25	26	28	11	WDRC	female	Public oral
S3	20	21	32	19	WDRC	male	Public oral
S4	39	41	41	15	CL	female	Private oral
WDRC = Wide dynamic range compression; CL = compression limiting

Appendix B
Threshold values for left and right ears (250 – 8KHz) for participants.
Threshold (L/R)
Subject #	250	500	1000	2000	4000	8000	Four Frequency PTA (L/R)
S1	25/40	30/40	55/50	55/60	55/55	60/60	49/51
S2	35/20	45/45	55/50	65/60	55/60	70/65	55/54
S3	60/45	50/30	65/15	50/15	20/10	30/35	46/18
S4	25/35	25/25	20/15	50/40	55/65	60/65	38/36
Mean							47/40
L/R = left/right ears.