What's the average cost of installation a subwoofer on a 2005 impala or does it depend on the subwoofer I want?

They have a wide range of subwoofers from cost effective to competition. If your looking for adove average sound without a high price, I recommend power bass brand speakers. Mine were around 300 but I have a custom built box also 2 tens hit hard too.

Good Afternoon Ritchie.....Best thing to do is to call us @ (513) 471-5602 so we can discuss the details of your install so we can give you accurate pricing. Our store hours are M-F 9-7 and Saturday 9-6. Thank you.