Antelope Audio A4-1B Analog Automated Opto Valve Compressor (Complete)

The Antelope Audio A4‐1B is a next‐generation analog compressor that fuses the classic warmth of an opto‐valve design with cutting‐edge modern workflow features.

Built to capture the musicality and smooth response of vintage optical tube units, it delivers expressive, transparent compression that enhances vocals, bass, keys and percussion with unmistakable analog character. Its pristine signal path and carefully tuned response make it equally at home on subtle dynamic control or rich, harmonically enhanced gain reduction.

Inside the A4‐1B, every element reflects Antelope Audio's uncompromising approach to analog engineering. Custom UK‐made transformers provide punchy low end, detailed highs and beautifully rich harmonics, while hand‐selected premium tubes give the unit its signature warmth and musicality. A modern, highly stable power supply with automatic voltage adaptation ensures cleaner operation, reduced noise and long‐term reliability.

What truly sets the A4‐1B apart is its unique hybrid workflow. Proprietary motorised potentiometers allow instant preset recall, remote operation and seamless DAW automation via the included VST3, AU and AAX plugin.

If you're ready to elevate your productions with authentic analog tone and next‐level workflow, the A4‐1B is an exceptional choice.

Features

• Authentic opto‐tube compression with a 100 percent analog signal path
• Custom UK transformers and premium tubes for warm, musical tone
• Continuously variable ratio, attack and release controls
• Automatic calibration for long‐term precision and stereo linking
• Modern PSU for stability, low noise and tube longevity
• Remote control via A4‐1B plugin (VST3, AU, AAX) with instant recall
• Proprietary motorised pots mirroring every hardware/software change
• Sidechain filters including low‐pass, high‐pass, band‐pass and de‐essing mode
• DAW automation for threshold, ratio, attack, release and gain
• Frequency response: 20 Hz to 20 kHz within 1 dB
• Max input/output level: +24 dBu
• Includes A4‐1B unit, power cable, USB‐C cable and documentation