I have type r speakers, which come with a crossover and tweeters. I'm planning on mounting the tweeters in the door, and crossover in the boot. The speaker cable attached to the tweeter is really small, and it wont be long enough to reach to the boot, if I used a larger speaker cable to extend it to the crossover on the boot, would the larger cable affect the sound quality??

I also have 12 gauge speaker cable, and some slightly larger speaker cables lying around, if I used up all of the 12gauge speaker cable, and used some other slightly larger speaker cable, would this effect the sound??
thanks in advance!

 

It might make a minimal difference in sound, but I doubt it would be noticable.

However, if your crossovers are passive and not adjustable, you can mount them under the dash. They will be out of sight, protected from the elements, and wouldn't take up any trunk space. The cable runs would also be MUCH shorter to the door speakers.

Just a suggestion.