What size are the factory speaker? Are those correct? What people are installing and do you need an adapter for the speaker? Thinking to put these but wasn't sure if fit or any good 1. Front Driver/Passenger: 6.5" 2. Rear Speakers: 6 x 9"
So, what's wrong with the factory speakers? They sound great to me, and they are phased in a way that centers the image for the driver.
Depends. Do you have JBL? Past Gen3's have been 6x9 front and 6.5" rear for non-JBL and 6.5 front & rear for JBL. JBL is harder to upgrade beyond just speakers but it's possible. Metra has new adapters (that didn't exist a year ago when I first tried to upgrade my speakers) that actually fit the speaker mounting holes on 2012-up Prius.
