Chameleon Labs 7721 Stereo VCA compressor
The Chameleon Labs 7721 Stereo VCA compressor is a powerful analog processor designed to make tracks and stereo bus sound more compact and powerful.
When designing the Chameleon Labs 7721 Stereo VCA compressor, the engineering team began with a blank slate and conducted a thorough evaluation of the details involved in creating a bus compressor for modern studios. By utilizing a voltage control amplifier (VCA) topology for detection and voltage control and designing a low-noise and transparent circuit, an acoustic “glue” was created that can consistently deliver punch and loudness to the signal.
The 7721 offers a classic range of adjustable settings, as well as controls that are exclusive to esoteric compressors. These include:
- Soft Knee / Hard Knee – This feature enables users to switch between a softer arriving compression effect and a faster arriving, limiting type effect.
- Peak / RMS – The Peak and RMS detection schemes are distinctly different. Peak detection engages the compressor by monitoring peak or instantaneous voltage signals, while RMS engages by looking at the average energy in the signal and comparing it to the threshold setting. These distinct modes of operation provide excellent solutions for specific problems.
- High Pass Filter – This filter allows users to filter out low frequencies and avoid pumping effects. It is particularly helpful when using the sidechain to more precisely control which frequencies are being compressed.
- Classic Controls – The Threshold / Attack / Release / Ratio controls provide a nice starting place for master transparency, with low ratios offering transparency, 4:1 providing more color, and higher ratios offering a tougher sound full of character. The Attack and Release controls can be used to respond to the tempo and feel of a track.
- Blend – This control allows users to blend, or mix, the original uncompressed signal with the compressed signal, providing another tool to achieve their desired objective.
- VU Meter – The Input, Outputs, and Gain Reduction levels can be monitored via the VU meter.
Features:
- Stereo compressor with VCA-based signal detection
- Super low noise, IC based input section
- Side chain input allows a separate source to be used as the compression trigger
- IC based, ultra-low noise output stage
- VU meter for Input / Output Level and Gain Reduction monitoring
- Super low noise internal power supply
- Selectable high pass filter
- Threshold, Attack, Release and Ratio controls
- Selectable detection type: Peak or RMS
- Selectable compression types: Soft or Hard Knee
- Blend control allows you to mix the compressed audio signal with the original signal
- Fully Balanced Output Stage
- Internal Universal Power Supply
Specifications:
- Impendances: Input >10kΩ / Output <50 Ω
- Input Connectors (XLR (f)) 50 kΩ, Side Chain Input (XLR (f)) 50 kΩ, Output (XLR (m)) 200 Ω
- Noise: better than -100dBu Input Terminated with 600 Ω, compressor ON and Output Gain set to 0dB
- SNR: 116dB at maximum output
- Frequency Response: 20Hz – 20kHz +/- 0.25dB
- Headroom: > 20dB output level
- Dynamic Range: 100 dB per AES17 Standard
- Common Mode Rejection: 100Hz – 10kHz >90dB
- Threshold: Applied between -15dB and +15dB
- Attack time in milli seconds – .1 / .3 / 1 / 3 / 10 / 30
- Release time in seconds – .1 / .3 / .6 / 1.2 / 1.5
- Compression ratio selection 1.5 / 2 / 4 / 8 / 10
- High Pass Filter: 60, 90, 130 or 200 Hz high pass filter applied to Side Chain detection signal
- Output Gain: -60dB to +20dB Output Level control
- PSU: 100V – 240V (50/60Hz), Switch mode PSU, fully shielded 3 amp peak output capability, quiescent consumption 0.5 Watts
Dimensions & Weight:
- Unboxed dimensions: Depth 29,5 cm, Width 48 cm, Height 4,4 cm (1HE)
- Unboxed weight: 5 kg
- Boxed dimensions: Depth 42,2 cm, Width 54 cm, Height 14,8 cm
- Shipping weight: 6,9 kg