The SLB300PRO is a new addition to the Yamaha lineup of Silent upright basses that achieves natural sound and resonance by using the SRT POWERED system to simulate studio-quality sound in which the body resonance of a double bass was implemented using high-quality microphones, all the while keeping a semi-solid body structure that emphasizes quietness and portability. The SRT system allows for 3 high-end microphone choices that emulate the sound of vintage high-end studio microphone, a classic dynamic studio microphone for clear, crisp signal, and another tube microphone with a rich deep funky feel and sound.