Antelope Audio A4-1B Opto-Valve Analog Compressor with Plugin Integration

The A4-1B is a single-channel optical tube compressor that combines vintage analog warmth with modern digital precision. Featuring an all-analog signal path with premium tubes and transformers, it offers DAW integration, motorized controls, and advanced filtering for unmatched studio flexibility.

Key Features

• Analog Circuitry: Purely analog opto-tube compression with transformers and premium tubes
• DAW Integration: Plugin-based control (VST3, AU, AAX) with instant recall and automation
• Motorized Controls: Real-time knob automation synced with DAW
• Side-Chain Filters: High-pass, low-pass, band-pass, and de-esser
• Auto-Calibration: Ensures consistent opto-cell response and stereo linking
• Compression Range: Ratio 2:1–10:1, Threshold Off to −40 dBu, Attack 0.5–300 ms, Release 50 ms–10 s, Makeup Gain up to +30 dB
• Signal Handling: Up to +24 dBu with noise below −80 dBu
• Power: Universal auto-voltage PSU (95–245 V, 50–60 Hz)

Technical Specifications

• Weight: 4.4 kg (9.7 lbs)
• Dimensions (W×H×D): 48.3 cm × 8.8 cm × 25.2 cm (19″ × 3.47″ × 9.92″)
• Box Weight: 6.5 kg (14.3 lbs)
• Box Dimensions: 64.0 cm × 14.0 cm × 35.0 cm (25.2″ × 5.51″ × 13.8″)
• Compression: Ratio 2:1–10:1, Threshold Off to −40 dBu, Attack 0.5–300 ms, Release 50 ms–10 s
• Gain: Makeup gain up to +30 dB
• Signal Handling: +24 dBu max I/O, Noise < −80 dBu
• Filters: High-pass, Low-pass, Band-pass, De-esser
• Power: 95–245 V AC, 50–60 Hz

Available Editions

• A4-1B Member’s Edition: Includes A4-1B Opto-Valve Compressor, 1-year access to A4-1B Plugin, 1-year access to Synergy Core Native
• A4-1B Complete Edition: Includes A4-1B Opto-Valve Compressor, 2-year access to Synergy Core Native, Perpetual access to A4-1B Plugin
• A4-1B Ultimate Edition: Includes A4-1B Opto-Valve Compressor, 5-year access to Synergy Core Native, Perpetual access to A4-1B Plugin

What's Included

• A4-1B analog compressor unit
• Power cable
• USB-C to USB-C cable
• Getting started leaflet
• DAW plugin license (depending on edition)