Good speakers, Here's what I'm trying to achieve. Options

[RabidTRD]

So I want decent bass, but I don't want to run subs... I've never liked the amount of space they take up and I don't want THAT much bass.

What I am looking to do is replace all of the speakers. All work fine and I have the GT model with the 6 speaker stereo and amp. I have a SONY XPLOD head unit that does 52x4 watts (208 total) with rear or sub selectable out. So what I want to do is put speakers in the rear that are decent on bass, use those primarily for the bass and then replace the tweeters to higher quality ones, and replace the door speakers with something to give me my mid range.

What are good brands that I can check out that wont rape me in cost, but be effective in the area's I'm looking. Does anyone here have any experience with high bass speakers that aren't subs? Could I run an 8" sub in place of a rear speaker and wire it the same as the speakers?

Thanks in advance for any advice.

[RabidTRD]

The GT-S I have came with a factory amp which the SONY is running through right now. At it's current point because of the rear selectable sub (aka I can already change my rear speakers into subs) I have enough bass to shake all of my mirrors and vibrate my house. That's with the factory speakers and the head unit at 21 volume.

It's not a cheap SONY head unit that you get at Walmart. This was one that they sold at Circuit City and was one of the first to ever offer iPod direct connect. I can control my iPod directly from the head unit. It's old, but it's clear, powerful, and never has any issues. I'm planning on upgrading to the new version of it because this one has a green faceplate and I'm doing a red interior theme.