a3 1997 1.6 sport - Horrible Noise through speakers

[seanseansean]

Hi I have installed and amp & sub into my car,

Getting horrible noise through the speakers, whining and you can hear the alternator through the system when you accelerate.

Got the ground wire into where the "standard" sub was and the live directly from the battery,

Can anyone give me tips on how to clean up this interference?

Thanks