Hi all,

I've lurked around the forum for a while and I've finally decided to post. I bought my hummer new in 2006, basically as plain as you can get (cloth seats, stock stereo, no nav, etc.)

I've been thinking about upgrading my stereo, I've put up with the crappy GM stock speakers for a while and its time for a change. I'm a fairly mechanical person, do all my own wrenching but I'm not familiar with stereos at all and I had a couple questions.

1. Why doesn't the system sound "good"? is it the amp? is it the Mid range speakers? in other words, can I improve the sound by just changing the front door mid range speakers?

2. If I change the amp does the radio head unit need to be changed also?

3. How would adding a small sub woofer affect this? would it need a separate amp?

this one might be a dumb question but I have the rear entertainment package, I can plug in my phone to play music through the surround sound on the dvd players but is this just a built in FM transmitter? it sounds pretty crappy.

any help with any of these would be appreciated. not new to online forums and I'm looking forward to joining this community!