Amazon.com: CQRobot Speaker 5 Watt 8 Ohm Compatible with Arduino Motherboard, JST-PH2.0 Interface. It is Ideal for a Variety of Small Electronic Projects. : Electronics
Amazon.com: Sound Storm EV4.400 Evolution 400 Watt, 4 Channel, 2 to 8 Ohm Stable Class A/B, Full Range Car Amplifier : Electronics
Amazon.com: Pyramid 10 Inch Car Subwoofer Speaker - 500 Watt High Powered Car Audio Sound Component Speaker System w/ 2 Inch High-Temperature Kapton Voice Coil, 85.6 dB, 8 Ohm, 60 oz Magnet - Pyramid PW1048USX : Electronics
Amazon.com: PRV AUDIO 8 Inch Shallow Midrange Buller Speaker 8MR400B-4 Slim, 4 Ohm, Shallow Mount Car Slim Speakers, 400 Watts Program Power 1.5 in Voice Coil, 200 Watts RMS, Compact for Doors (Single) : Electronics
Sound Ordnance™ B-8PTD 125-watt compact powered subwoofer at Crutchfield
Amazon.com: Skar Audio FSX65-4 6.5" 300 Watt 4 Ohm Pro Audio Midrange Loudspeaker, Each : Electronics