The Tube-Tech CL-1B Compressor

tube tech cl 1b compressor

The Tube-Tech CL-1B has earned a legendary reputation in recording studios for its smooth, musical (whatever that means!) compression and unmistakable analog sound. Loved by engineers for its ability to make vocals sit perfectly in a mix, the CL-1B represents the modern evolution of classic optical compression.

History of the Tube-Tech CL-1B Compressor

The Tube-Tech CL-1B is a modern classic born from a passion for vintage tube technology and the desire for musical, transparent compression. Designed and built in Denmark by Lydkraft, the CL-1B quickly became a studio favorite due to its simple controls, tube tone, and reliable performance. It draws from the spirit of the classic Teletronix LA-2A but introduces its own distinctive sound and functionality.

What inspired the design of the Tube-Tech CL-1B?

The CL-1B was inspired by vintage optical compressors such as the LA-2A, known for their smooth gain reduction and natural response. However, Lydkraft’s founder, John G. Petersen, aimed to refine that concept with higher precision, more flexibility, and a quieter noise floor. The result was an optical compressor with variable attack and release controls, something not found on earlier designs, making it more adaptable to different sources and genres.

How does the Tube-Tech CL-1B achieve its signature sound?

At its core, the CL-1B uses an opto-cell to control gain reduction, where a light source and a photoresistor work together to create a smooth, program-dependent compression curve. The unit’s all-tube signal path, combined with custom-wound transformers, delivers harmonics and subtle saturation. This combination gives the CL-1B its trademark clarity and depth—qualities that translate beautifully to vocals, bass, and acoustic instruments.

When was the Tube-Tech CL-1B first released?

The CL-1B was introduced in the mid-1980s, at a time when solid-state compressors dominated the market. Its hand-built construction, tube topology, and optical circuit made it a standout piece of gear that bridged vintage sound with modern reliability. Over the years, it became a fixture in high-end studios and mastering rooms around the world.

Why did the Tube-Tech CL-1B become so popular in modern recording?

Its popularity comes from a balance of character and control. The CL-1B adds subtle harmonic color without overwhelming the source, while its variable controls allow engineers to fine-tune the compression envelope. It performs equally well on lead vocals, bass guitars, or entire mixes, offering a polished sound with minimal effort.

  • 1985: Tube-Tech CL-1B released.
  • 1990s: Gains global recognition in professional studios for vocal and bass applications.
  • 2000s: Updates to internal components improve reliability and consistency.
  • 2010s: Widely emulated in digital plugin form by major software developers.
  • Today: Still hand-built in Denmark, maintaining its status as a studio staple.

Software Emulations

  • Softube Tube-Tech Compressor Collection
  • UAD Tube-Tech CL 1B Compressor

Tips and Techniques

  • Use Gentle Ratios for Natural Vocal Compression

    Set the ratio around 2:1 and adjust the threshold so the gain reduction hovers around 3 to 5 dB. This approach retains natural dynamics while subtly controlling peaks, adding smoothness without squashing the life out of the performance.

  • Set a Medium Attack for Smooth Transients

    Start with an attack of around 3 to 5 milliseconds. This lets initial transients pass through before the compressor clamps down, preserving the punch and clarity of the source while still adding body and warmth.

  • Dial in Slow Release for Vocal Sustain

    Try a release setting between 200 and 400 milliseconds. A slower release allows the compressor to breathe with the performance, creating a natural, sustained vocal presence that sits well in the mix.

  • Use the CL-1B on Bass for Even Dynamics

    Set the ratio to 4:1 and use a medium attack with a slow release. This setup evens out low-end fluctuations that helps the bass lock tightly with the kick drum, giving the mix a solid foundation.

  • Try the CL-1B on Acoustic Guitar

    Use a low ratio (around 2:1) with a fast attack and medium release. This smooths strumming dynamics and enhances the guitar’s body without dulling its brightness, resulting in a more balanced performance.

  • Spice Up Vocals with Tube Harmonics

    Drive the input slightly higher while compensating with output gain. This introduces gentle tube saturation that adds fullness and weight, particularly effective for thinner vocal recordings.

  • Use Multiple Stages of Light Compression

    Instead of heavy compression on one insert, apply two CL-1Bs or a CL-1B followed by another gentle compressor. Each stage handles a small amount of reduction, preserving tone while maintaining consistent control.