Can I add higher volume if I am hearing impaired?

I am in my 60's and due to they type of work I did my hearing is compromised. Having an iphone and lisening to music in it current configuration is not a good fit for me. I need the ability to increase the volume beyond the iphones current limits. Is there a way to do this? I understand persons with good hearing could abuse the ability to increase sound volume beyond safe hearing limits.I also understand why Apple has set volume limits so they don't get law suit by not protecting people against themselves.

Hearing aids are not a good fit for the iphone. I know there are bluetooth hearing aids but they are outside my budget. I am asking the engineering department to find a way to let those of us with hearing issues address our sound volume, balance and even eq so we can have a confortable lisening volume. I would be willing to sign off my ability to hold Apple resonsible for any hearing impearment that might result from changes made to the current levels of sound reproduction.