[Elecraft] CW for those with Poor Hearing

[Harry Yingst via Elecraft]

While in the Navy I damaged my hearing from exposure to loud noises (Naval Aircraft)Since then I've always had a real struggle copying CW (but I'm stubborn and keep trying)

I was playing around with the pitch and found that the higher frequency toneshave a ringing to them but as I went lower in pitch the ringing faded quite a bit.
So I'm basically looking for tips to help me to be able to copy better.
Thank you