Don't confuse speakers with noise reduction systems though.
If you have a noice problem, then a circuit is needed to handle that - for those I don't have much experience - my mobile operation is FM. But there are a couple of speakers that are supposed to be OK.
As to external speakers in general, it's hard to give advice since preferences tend to vary so much. I will say that while I think matching speakers look nice in the lineup, they are not always superior, and are often quite expensive, although some do come with noice cancelling functions.
My personal fave speakers are 5" full range with big magnets - they seem to work great for communication use and don't require large amounts of drive to be audible. For my mobile, I use an MFJ "Clear Speech" $13. speaker, for me the secret is that the speaker is attached to the driver's headrest so it's right at my ear - takes very little volume even with window open.
You pays your money and takes your chances: The contents of this posting are personal opinions. Persons trying to find motive, plot, logic, truth or beauty will be punshed severely under law.