If the sound quality of your earphones is not good and you are having difficulty hearing what you are playing, you may need to make your earphones louder. You can amplify the sound of your earphones by using an amplifier adaptor and an audio device. Amplification is a relatively simple process and once done could vastly improve the quality of your listening experience.
Determine the size of your earphone jack. Most earphones come with 3.5mm jacks, however you need to know the exact size of yours; step two will be much easier if you know the size. If you're not sure of your earphone jack size you could go to your local electronics store and ask them to help you.
Buy an amplifier -- you can get one from any good electronics store. You must buy an amplifier that has a port compatible with your earphone jack so take your earphones with you when you buy the amplifier.
Connect your earphones to the amplifier.
Connect the amplifier jack to your audio device.
Play your audio device and test the volume.
If you are still unhappy with the sound you can adjust the amplifier volume to the level you want.
If you do need to adjust the amplifier volume, do it slowly so you don't harm your hearing with a sudden increase in volume.