What's the 2008 Cadillac CTS speaker size?

The 2008 Cadillac CTS is equipped with 6 3/4 inch front door speakers; 5 1/4" rear door amplifiers, one rear deck subwoofer and front pillar tweeters. The CTS Sedan equipped with a 3.6 liter 6-cylinder engine also comes standard with steering wheel mounted Audio and cruise controls; satellite radio; an AM/FM stereo; a diversity antenna and 8 total speakers. All trims also feature Bose Premium sound and rear 12 volt power outlets. Other standard amenities include front seatback storage; a leather steering wheel; simulated wood-trimmed doors, a leather and wood trimmed shift knob and front reading lights. The CTS offers 18 miles per gallon in the city and up to 26 miles per gallon on the highway.