can anyone help me about my project??

im creating a portable mp3 speaker by using a Mobile speaker(motorola v3) and a old headphone jack and im not satisfy on the loudness of it. so, can anyone teach me how to make this much more louder like in motorola cellphones??

evrytime i plug it to my computer speaker the loudness is same as mobile speaker.but if i plug it to the mp3 player the loudness is too low.

help me pls..

More information needed -

Does your MP3 player have a headphone jack?

If the answer to the 1st question is "Yes", are you plugging it into the headphone jack on your MP3 player?

I answered on the other website:
1) The cheap tiny "speaker" produces awful sound quality. It is really just the driver from over-the-ears headphones.
2) A power amplifier will make it louder but will blow it up.
3) Today a newspaper ad shows a mini cube speaker with built-in amplifier for only $5.99 each. It is small so it will also sound bad but not as bad as yours.

Hint: The videos you posted on the other website demonstrate the awful sound from your tiny "speaker".