I have an 04 Navigator with premium factory sound (yeah right). For now I was wondering if I could get away with using the factory speakers with the Z1. Does anyone know the impedance on the factory speakers? I don't want to fry this baby. On another note, I have not been able to find a store that carries the guide speaker (CD-TS37-GP). Is this for the voice nav? Is anyone using something else?

Thanks.

I have an 03 Aviator and I did. It worked ok, I still replaced the speakers with some boston acoustics. I'm pretty sure all stock car speakers are 4ohm, so are the after market ones too. I believe you will be fine. Changing mine out was probably unnecessary. They sounded ok too, but the new BA reall crank. I kept the stock sub and amp and in the Aviator (yours is probably the same) I needed a 5v turn on for the sub amp, not 12v so I needed to put in a 7805 with a couple caps for the 5V hookup. Just an FYI.

thanks ducatiboy. I saw the pics you posted for your Aviator - very, very nice. I will be adding an amp for the new 12" Infinity Kappa sub I'm adding, and later I want replace the rest of the speakers. Haven't heard any BA speakers yet so I'll have to give them a listen. I didn't think BA made 5x7 or 6x8 component speakers. What did you put up front?

I got these, 4 of them and replaced all the door speakers:

http://www.crutchfield.com/S-L1fGeFvzhG ... 0&I=065S85

And I kept the sub. My cousin doesn't think I'much of an audiophile cause I think Sat radio sounds pretty good (he says it's so bad it hurts his ears to listen to it) and I can't tell the difference between my $2K stereo at my house and his $30K stereo at his. But I think these sound pretty good.

Crank up the head unit and sub and play something like Pink Floyd the Division Bell and I think it sounds really nice. Very clear and loud enough for me. It might not rattle my neighbor's windows but I think it sounds great.