Check the listing for details. Stetsom Digital Bass Restoration Processor Tremor Control 12.6V STT42. Color: Black, Condition: New, Made in Brazil. Listed at 149.99 USD. The Stetsom Tremor STT42 is perfect for bringing lost bass back to your music and taking your car audio system to the next level. Designed with advanced digital bass restoration technology, this processor analyzes your audio signal and reintroduces missing low frequencies for deeper, richer, and more powerful bass. Whether your music source is compressed or lacking punch, the Tremor STT42 restores impact and adds dynamic low-end energy without distortion. Fine-tune your sound using the Wide and Sweep controls to dial in the exact bass range you want, then adjust bass level on the fly with the included dash-mounted Tremor Control. Compact, easy to install, and highly effective, this processor delivers a more immersive and exciting listening experience from the driver’s seat.