Used Synergy OS Guitar Preamp in great condition, delivering boutique-level overdrive inspired by the legendary Dumble-style tone. This all-tube preamp module features dual channels with independent gain and volume controls, offering exceptional touch sensitivity and dynamic response. Designed for use with Synergy modular systems, it captures smooth cleans to rich, harmonic overdriven tones. Perfect for blues, jazz, and fusion players seeking expressive and articulate sound with premium tonal flexibility.