Replacing with aftermarket speaker:
1. Check the ohm rating on the back of the factory speaker (usually, if it's the only one on the channel, it will be 4 ohm; if it's one of two speakers on the channel wired in parallel, it will be 8-ohm)
2. measure the mounting hole spacing and depth of the original speaker, as well as the available space (if any) behind the original speaker
3. shopping for replacement, look for the matching ohm rating, the same diameter, as close as you can get to the same hole spacing, and no greater depth unless there is additional space behind.
4. if the OEM speaker is plastic'd into a unique mounting, you can usually disassemble the mounting to the point where you can insert a good speaker where the original speaker was, then reassemble (PITA, but I've done it on my S70). Somewhere here on the board there are instructions on disassembly of the plastic speaker surrounds.
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We have met the enemy and they is us. [Pogo] S70 T5 cop car : Rough Rider suspension, Walmart fog lights, eBay speakers, ambiance by Pall Mall, trim by Le Duc d'Tape, 8-channel THD by OEM amps