200T EDC Speakers

Hi all

I am the proud new owner of a 2013 200T EDC in black. I love the ride, engine and gearbox but the only thing to let it down is the speakers. They sound terrible and there is almost no bass. I've done a lot of Googling but can't find a guide on upgrading them. Has any one replaced the speakers, if so did it improve the sound? Or, should I look to install an amp as well?

Thanks
Ash