176 Limiting Amplifier


The Retro Instruments 176 is based on a Bill Putnam classic, the UA 176. The 176 faithfully reproduces the sound of the 1960s original with new features for the modern recording studio. The Retro Instruments 176 provides one of the most desirable compression signatures in recording history.

Learn more about the Bill Putnam original.

  • Features
  • Authentic variable-mu tube design
  • Precision Knob scales for easy recallability
  • Continuously variable attack and release time
  • Four settings of compression ratio from soft compression to limiting (2:1, 4:1, 8:1, 12:1)
  • Wide-Range Sidechain Highpass Filter
  • Vocal Asymmetry Tool
  • Hard-wire Bypass Switch
  • Interstage Transformer Bypass Switch
  • High Quality VU Meter switchable between Input, Output and Gain Reduction
  • XLR input and output connections
  • IEC power connector
  • 115/230V AC Mains
  • Integral tube balance test
  • Easy stereo strapping of two or more units
  • Selected NOS tubes and components
  • Specifications
  • 20 dB of available gain reduction
  • Signal to noise ratio of greater than 76dB
  • Flat frequency response within 0.5dB from 20-20,000Hz
  • Harmonic Distortion of less than 1% from 0-15dB gain reduction


  • Seawell Studios
    Feb 10, 2021

    Retro Instruments 176 Review (THE best vocal compressor ever?)

    I think the Retro Instruments 176 is the best vocal compressor ever made! It combines the tone I love in a great vari mu compressor with the speed similar to a FET. It’s truly the best of both worlds to me. Check out this review and see if you agree!

    - Seawell Studios See more...
  • Vintage King Audio
    Jul 1, 2015

    Retro Instruments 176 Limiting Amplifier Overview by Sweetwater Marek Stycos from Audio Alchemist presents the Retro Instruments 176 tube limiting amplifier. The Retro 176 is a faithful re-creation of the Bill Putnam’s 176, which paved the way for the legendary 1176. The Retro 176 gives you precise dynamic control with a wide sonic range: use it to just clamp down on peaks, or push it hard to add energy, excitement and brightness. For drums and bass especially, this is an incredibly fat-sounding dynamics controller.

    176 SweetwaterSound-review

    - Marek Stycos See more...

What people are saying about the Retro Instruments 176

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