The Ampeg SVP Pro Bass Preamp is a high-quality amplifier head designed specifically for bass guitars. Made by Ampeg in the United States, CIRCA 2000+ this preamp offers one channel of sound and utilizes vacuum tube technology. fully functional and in excellent shape. It is made for performance and is part of the SVP Pro product line. One of the best for shaping your own sound. If you can find one it may sell for well over $1000.