stereo wiring question

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
I replaced head unit, bypassed the factory amp (ran new wires from HU to speaker lines from amp, following this guide), installed new speakers in doors, and everything sounds ok...but, I wasn't expecting the tweeters in the front pillars to work...they are putting out sound. presumably there was a crossover in the front to split sound between tweeters and the door speakers. I guess I figured this was built into the amp, but maybe not? Are there passive crossovers after the speaker leads from the amp output? I basically want to ensure I'm not sending the full signal to the tweeters OR a reduced signal (mids/lows) to the doors (as they are full range speakers). Any guidance/insights appreciated!
 

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
any help here? also, what's the best option for routing a power cable through the firewall for an amp? ideally passenger side. i see a clearish tube by the factory amp by the glove box...could i just drill through there?

thanks!
 

K-rover

Well-known member
Jan 15, 2010
2,163
62
Raleigh, NC
There's a black grommet just to the right of the blower motor under the glove box.

Can't help with the amp. I bypassed the factory amp all together...
 

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
Thanks for reply! I bypassed the amp as well...i was just surprised to still get sound from the tweeters in the pillar oncw i rewired direct from HU to the cables that went into the amp. Do you? Gonna go look for that grommet...tho i don't know what a blower motor looks like :/
 

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
sheesh...I can NOT find this grommet or another way through the dash. Should I be able to see this without removing anything more than the glovebox?
 

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
where should I see it from engine bay? do I need to remove washer fluid reservoir to access? so frustrated this is holding me up...ugg
 

logan_gibson

Well-known member
Dec 20, 2016
258
47
Alabama
I was talking about the two I circled here.
Not sure about the one you selected, but I can check it when I get home.

Yes, you will need to remove the bottle to access the holes.

1605557449296.png
 

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
I was talking about the two I circled here.
Not sure about the one you selected, but I can check it when I get home.

Yes, you will need to remove the bottle to access the holes.

View attachment 60057
Ah, gotcha...not sure your circles came thru on first pic. I was *just* able to squeeze power cable thru w/o removing water bottle! Def not the "1 inch opening" I've heard others mention, and with no gasket around the wire this may not be very smart, but we'll see (that's what fuses are for, right?)! Thank you again for the help!!
 

logan_gibson

Well-known member
Dec 20, 2016
258
47
Alabama
You can get a bulk pack of grommets that will fit that hole and wire.

Lowes also has some in their specialty parts bins with the bolts.
I would highly recommend putting a grommet in, or at least coating the hole in some silicone/etc.


* I didn't circle them in the first picture, my mistake. Would've been easier to explain If I would have done that.
 

mc9735

Active member
Apr 29, 2017
41
3
Chattanooga
Gotcha - I will at least do the silicone. Were you able to check that other "question mark" spot - is that a gasket/pass thru?