I know this is weird, but here it is:

When I installed my new headunit (Alpine IDA-x305) and speakers (Polk DB651) on my MY03, I was thinking why does it still sound like crap. The sound didn't improve very much, or at least I thought so.

So today, I was playing some music with some bass, and my co-worker opened the door while the car was still on with the stereo on, and the sound quality improved by 10x.. I asked him to open and close the door, and yes, it did sound better. I tried my door, and it sounded better with the door open as well.

I thought maybe it had something to do with the extra volume of space (don't ask) since the door was open so we tried opening the windows, but it still sounded like crap, but once the door was open, it sounded better again.

I'm pretty sure it is not just in my head.. I think? The improvement is mostly with the bass. It is also more evident in certain songs. In some songs, I couldn't tell the difference, but on certain songs, the improvement was very significant.

I'm thinking there is some lose wires, ground, etc. going on somewhere.. or maybe I'm just crazy.

Any thoughts?

UPDATE: It turns out, the speakers were out of phase. I switched the driver's side speaker wires. They sound 10x better now. Thanks!

 

Maybe because the speaker isn't firing into your leg?

 

Speakers out of phase.

 

Even if the door is only slightly open, it made a difference so I don't think that's it?

 

So the fault is with speaker harness connection or with the Alpine harness? I guess I need to check both.

Thanks for the tip!

 

It turns out, the speakers were out of phase. I switched the driver's side speaker wires. They sound 10x better now. Thanks!