Why You Need The Retro Instruments 176 Tube Limiting Amplifier: Designed to provide the character of vintage tube compression in the modern recording studio  Modeled after the superb UA 176 limiter with added features and conveniences. Provides one of the most desirable compression signatures in recording history Easy stereo strapping of two or more units XLR input and output connections Four settings of compression ratio Precision Knob scales for easy recallability Authentic variable-mu tube design 115/230V AC Mains  Vintage Design for modern recording Retro Instruments is changing the way the world sounds by creating classic style audio gear for modern recording. Retro products keep what made the originals the best of the best, updating vintage design with modern features to improve functionality - creating unique and innovative gear that sounds, looks, and feels vintage and state-of-the-art in equal measure.