I know I can simply replace the speakers. I don't know anything about the specifics of what the head unit can and can't drive. I've had the vehicle for 5yrs now and the audio is starting to be a bit worn an distorted. I'm going to flat out admit I haven't built a system out since I was in high school over 20yrs ago. I'd take it to a shop to have done. In the past I had a Jeep Grand Cherokee that was extremely hard for the shop to upgrade the system on. That was in 2015 so I'm hoping practices and technology have changed since then. I have a 2017 Land Rover Discovery TD6 HSE with the Meridian sound system (oddly I've never seen the sub so I don't know if it has one). If I wanted to replace all the speakers what do I go with for a better sound system? Which brands to stay away from and which really work well together?