Tube-Tech CL 1B Optical Tube Compressor

The Tube-Tech CL 1B is a classic tube-based optical compressor with huge analog sound and a surprising level of versatility. It's all-tube design delivers warm, harmonically rich compression, while custom transformers ensure a clean signal path with plenty of headroom to handle the most dynamic tracks. A unique sidechain circuit with two busses provides options for stereo linking and parallel compression using multiple CL 1B units. Familiar and easy-to-use controls let you quickly dial in various settings, from smooth compression for your vocal chain to aggressive, distorted pumping for stereo drum busses. The CL 1B's musical-sounding compression and versatility have made it an iconic studio tool, and now you can bring that legendary sound to your studio.

ALL-TUBE DESIGN

The CL 1B employs a tube-based push-pull amplifier stage that imparts smooth, natural harmonics to any signal passing through it. At low levels, you'll hear a slight added warmth, while pushing it harder brings out a more saturated sound. Simply fine-tune the level you send to the input, let the tube circuitry flavor your tracks with its signature warmth, and adjust the output level as needed. This CL 1B's tube-based design tamps down the brittle tones that solid-state compressors don't, so all your vocals and instruments come out sounding rounder and smoother without losing any "punch".

CUSTOM INPUT AND OUTPUT TRANSFORMERS

On the in and out stages, the CL 1B uses custom-designed transformers with a static screen between primary and secondary wirings. Both transformer stages are balanced and fully floating to reject noise while preserving low-frequency weight. No matter what signal you send through the unit, these premium transformers deliver high headroom and ultra-clean amplification before the audio even reaches the gain-reduction element. The result is a transparent signal path that sets the stage for the tubes to work their magic on your tracks.

EASY-TO-USE CONTROLS

Dialing in the CL 1B is intuitive thanks to its straightforward front-panel layout. Individual knobs for Ratio, Threshold, Attack, and Release let you tailor the compressor's response to bring out the best in any signal. The Attack and Release behavior can be set to fixed, manual, or combined time-control modes to suit any source from classical strings to rock drums. The clickless bypass switch engages the compressor silently, while the clear VU meter displays your levels at a glance. The variable Gain knob offers up to 30 dB of additional volume to make up for heavy compression.

UNIQUE TWO-BUS SIDECHAIN CIRCUIT

The CL 1B’s unique sidechain circuit features two different busses, letting you link multiple units for stereo compression, parallel sidechain processing, or complex control groups of multiple compressors. By connecting units via the rear-panel TRS jacks and setting each unit’s dedicated bus selector switch to either Bus 1 or Bus 2, you create separate detector paths so one group can provide gentle stereo “glue” while the other drives aggressive parallel compression. This architecture goes far beyond simple stereo linking or external sidechaining, enabling countless creative possibilities.

AN INDUSTRY-STANDARD VOCAL COMPRESSOR

Introduced in 1991, the Danish-made Tube-Tech CL 1B quickly became the go-to compressor for vocals in studios all around the world. It's smooth, transparent optical compression tames dynamic peaks without introducing unwanted artifacts, helping any track sit perfectly in a mix. Whether you’re tracking drums, layering backing vocals, or polishing a stereo bus, this legendary Tube-Tech hardware compressor delivers musical tone with flexible control.

TUBE-TECH CL 1B FEATURES:

• All-tube design with push-pull amplifier
• Unique low-distortion gain-reduction element
• Two sidechain busses for interconnecting multiple compressors in stereo or parallel
• Custom output and input transformers with static shielding
• Continuously variable attack and release time
• Customizable attack and release behavior with three positions: fixed, manual, and hybrid
• Analog VU meter for monitoring input, compression, and output
• Gain range: +0 to +30 dB)
• Variable Threshold: 0 to -40 dBu)
• Frequency response @ -3 dB: 5 Hz to 25 kHz
• Low noise: < -75 dBu @30 dB gain
• Clickless bypass relay
• Vintage-inspired optical compression design from 1991