pioneer hu give good signal from 45-70% of total volumn.

It is normal to turn your volumn knob. Same as your gas pedal when you want to speed.

No matter your hu is from 0-10 or 0-60 or 0-100, it still give you the min and max at the same. It's a matter of how many step it has.

So, crank it hard.....

hearing lose can be solve by regular check up and compensation from the missing frequency. You still can get a standard from the sound if you know how much you loss. So this is not an excuse.