Speakers: Aftermarket, Ohms, Resistors, and More

Let’s talk Speakers – from Aftermarket to resistors and beyond

Door speakers, dash speakers, new replacement Polk/Infinity/Pioneer speakers, plus Volvo OEM amps and 20-watt 8-ohm resistors… Is your head spinning yet?

Making sense of how to upgrade or replace bad speakers.

kcodyjr » If indeed your front door and dash series are in “tandem”, or rather in series as you’ve described the behavior, the dash is completely flattening what little bass the door speakers can produce, and a good bite of the midrange as well.

From the factory, the front dash and doors are independently wired to the head unit, and indeed have their own separate pins. With the OEM amplifier in the car, the dash are still driven directly from the head unit, and the amp powers the other six. Hence, the front door speakers are actually 4-ohm.

If you’ve got an aftermarket head unit, or otherwise modified, all bets are off.

The rear speakers are wired in parallel and are supposed to sum to a four ohm load. The rear door is a 6-ohm and the rear deck seems to have a resistor in series from the factory – I haven’t taken testing equipment to it, so I’m not certain exactly.

I’ve replaced my four door speakers with four-ohm units, and did locate mounting plates to let me put any common aftermarket tweeter in the dash. I’ve got the part number listed in an 850 speaker replacement thread. It sounds very good with the 4×40 OE amp in the dash, but the rear door speakers are overwhelmed by the deck speakers when you’re sitting in the back.

My plan is to restore impedance balance by installing an aftermarket amp in the trunk to drive the rear deck, so the amp once again sees a 4-ohm impedance. I’ll choose the amp to filter out everything above 100Hz, effectively turning the factory rear deck speakers into near-sub woofers. No other cone will ever match the trunk as well as those originals, despite their primitiveness.

New speakers

Last Updated on August 9, 2022