ART Pro Audio Pro VLA III Two Channel Multivoice Tube Opto Compressor

The ART Pro VLA III is a two-channel tube optical compressor that brings variable levelling amplifier topology to project studios and tracking rooms. Each channel features a 12AX7 vacuum tube gain stage driving an opto-attenuator for smooth, program-dependent compression with ten user-selectable voice characters per channel. The all-analogue signal path offers up to 20dB of gain reduction with attack times from 10ms to 60ms and release times from 50ms to 5 seconds, while true hard-wire bypass switching preserves signal integrity when processing is disengaged.

Balanced XLR and TRS connectors handle input and output duties across a frequency response of 20Hz to 30kHz with total harmonic distortion below 0.5 percent. The ten compression voices span clean VCA-style levelling to full tube saturation, each engineered around different opto-cell time constants and tube gain staging. Front-panel metering displays gain reduction via a 10-segment LED ladder, while independent threshold, ratio, attack, release, and output gain controls provide detailed shaping of dynamics. Stereo-link capability synchronises both channels for cohesive bus compression or mix-down applications.

Housed in a single rack-space steel chassis, the unit operates on standard mains power with an internal toroidal transformer for low electromagnetic interference. The combination of tube warmth and optical smoothness addresses vocals, bass, drums, and full-mix material where transparent gain control with harmonic character is required. Each channel operates independently or linked, allowing simultaneous processing of stereo sources or parallel compression techniques across separate programme material with consistent tonal response.

Features

• Dual-channel tube optical compressor with 12AX7 vacuum tube gain stages
• Ten user-selectable compression voices per channel for tonal variation
• Up to 20dB of gain reduction with 10-segment LED metering
• Attack times from 10ms to 60ms, release from 50ms to 5 seconds
• Frequency response of 20Hz to 30kHz with THD below 0.5 percent
• Balanced XLR and TRS inputs and outputs on each channel
• Stereo-link mode synchronises both channels for cohesive bus processing
• True hard-wire bypass switching with single rack-space steel construction