[Don Ro]

I grew up shooting at the age of 10...no ear protection.
Rode motorcycles with no helmet back then.
Hearing loss almost kept me out of the military.
Jet engines in the military.
Loud home music systems...loved loud and crystal clear head phones.
At 35 yrs. of age my ex g/f was an audiology Dr. who tested me for loss and recruitment.
These days (70 yrs. old) I don't like gatherings because I can't make out most of the conversations.
Watching movies on TV I use the closed caption feature.
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Recruitment causes your perception of sound to be exaggerated. Even though there is only a small increase in the noise levels, sound may seem much louder and it can distort and cause discomfort. Someone with recruitment can have problems only with specific sounds and frequencies or may have problems with all sound in general.

The theory of recruitment is that as the hair cells in your cochlea become ineffective, they "recruit" their (still working) neighbor hair cells to "hear" the frequency the damaged hair cell was supposed to hear, in addition to the frequency the still working hair cell was supposed to hear. This increases the signal from the still working hair cells.

The sounds reaching our brains appear to be much louder that normal. This is because the recruited hair cells still function in their original critical bands and also in the adjacent one(s) they have been recruited into.

The net effect is that people who have recruitment along with their hearing loss will experience an increasingly narrow range between the softest sound they can hear (caused by the hearing loss) and the loudest sound they can comfortably tolerate (caused by the recruitment).