Any different speaker model will have different sound. If it's worse or better is up to you. If the speakers are working fine, no need to change them. I have a pair or nice Logitech 4.1 speakers I bought close to 20 years ago and they still sound fine. Speakers are not like computers, just because there is a newer model does not mean it's any better sounding. And if the others still sound and work properly there is no need to change them.