Was frustrated at lack of feel at tire limits, so tried a cheap kit like this to get LFE wheel slip data to my butt. Instant lap time improvements for me, even
Source 50 watts Amplifier for bass shaker control box on m.alibaba.com
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Amazon.com: Dayton Audio BSA-200 200 Watt Bridgeable Stereo Bass Shaker and Subwoofer Amplifier with Remote - 110 WPC RMS at 2 Ohms, 230 Watts RMS at 4 Ohms Bridged : Electronics