Spectra Sonics 610 Complimiter circa 1978

The 601 compressor/limiter module (right) was introduced in 1969. It was first implemented in the Spectra Model 610 Complimiter (below). It acts as a separate compressor and peak limiter, or it can perform both functions simultaneously. Today, the 601 is still the fastest, quietest, and most versatile analog compressor/limiter available. The 601 module is the heart and soul of each of our Complimiter models. Choose which Complimiter best suits your application:


The Model V610 is a major improvement on the 610 Complimiter, now 45 years after it's original release. The V610 has high resolution detented controls, as well as lower distortion, noise, and a +24dBu output. For tracking, mix buss, and mastering applications.


The Model 610 is the original Complimiter introduced in 1969. It utilizes the 601 compressor/limiter module, with a 101 Preamplifier for make-up gain. Two 610 Complimiters can be interconnected for stereo use via the 610 SI Accessory.

The Spectra  Model 611 Complimiter is a hand-built, discrete design utilizing custom transformer I/O that accepts a balanced line input, microphone input, or high-impedance ¼” input and is designed to be placed in FRONT of the mic preamp in your signal chain, thereby eliminating transient peaks as close to the source as possible. Removing peaks before the preamp allows the preamp to more accurately reproduce the source before the recording device.

Additionally, the compressor portion of the Model 611 Complimiter can be used to control the overall dynamic range – everything from evening out a bass track, to making a kick drum boom, or crushing a drum room mic. Plus, its small, portable extruded enclosure makes it easy to dial in sounds in the studio or control room alike. Perfect for producers and session musicians on the go.


  • Dramatic improvement in dynamic range and harmonic content

  • Reduced distortion due to the elimination of transient overload

  • Instantaneous control of dynamic range (compression function)

  • Unequaled Guitar/instrument sonic performance with either passive or active instruments pickups

  • No requirement for de-essing or high frequency equalization

  • Direct termination of microphones (phantom power required)