Well I have a method that will make every sound lounder e.g. tapping the keyboard produces a lound sound in my ears. I think if other people try this they can have better hearing. I don't know where this will go, but I will put it here.
This is simple to do, but it takes about half an hour. First get a cup and fill it with water. Now look at the cup and follow these simple rules:
. Don't move
. Don't think
. Don't get distracted this means no t.v. on
. Let go of everything i.e. don't care about nothing
. The place should be quiet
Now here comes the improtant bit. Whilst looking at the glass keep on blinking really hard, this means blink with your face i.e. screw up your eyes like a angry person to close them. Now keep on doing this for about ten minautes, your muscles will become tired and will hurt when this happening keep on doing it. Also do blinking randomly like sometimes fast and sometimes slow.

Note: I don't know if you need to blink really hard or just blink normally, tomorrow if my hearing is normal I will try blinking normally to produce effect.

Now can someone else try this and say if your hearing gets lounder.

P.S. Make sure you try this more then once. Also the biggest sign it is working is you have a big vibrating feeling in your ear.