Fender Rumble 40, Black/Silver - The all-new Rumble Series is a mighty leap forward in the evolution of portable bass amps. Re-engineered from the ground up, new Rumble amps are lighter and louder than ever, with even more power and a classic Fender vibe. A newly developed foot-switchable overdrive circuit and versatile three-button voicing palette deliver powerful tones ideal for any gig.