Chameleon Labs 7721 Stereo Compressor
Proudly made in Seattle, Washington, USA, the Chameleon Labs 7721 Stereo VCA compressor is a powerful analog processor designed to make your tracks sound more compact and powerful. When designing the 7721, Chameleon's engineers started with a clean sheet of paper and deeply evaluated the details associated with developing a bus compressor for the modern studio. Basing detection and voltage control on a voltage control amplifier (VCA) topology and designing a circuit that provides low noise and transparency, the team created an acoustic "glue" that is capable of consistently delivering punch and loudness to the signal.
Hear the 7721 bus compressor on drums and full mixes in zZounds' demo video:
Marcelo at Chameleon Labs takes you on a deep dive into the 7721 compressor's design:
The 7721 provides a classic set of adjustable settings as well as controls only available on esoteric compressors, including:
Soft Knee / Hard Knee:
Allows you to change between a softer-arriving compression effect and a faster-arriving, limiting type effect.
Peak / RMS:
This control allows you to choose between the Peak and RMS detection schemes that are quite different. Peak detection engages the compressor by monitoring peak or instantaneous voltage signals. RMS engages by looking at the average energy in the signal and comparing it to the threshold setting. Very different modes of operation that provide great solutions for specific problems.
High Pass Filter:
When the HPF is engaged, the compressor doesn't affect frequencies below the cutoff. When the Side Chain input is engaged, the filter is applied to Side Chain detection signal. If you decide to use a Side Chain signal as the compression trigger signal, you can use the High Pass Filter to high-pass the audio signal and avoid pumping effects.
Threshold / Attack / Release / Ratio - Low ratios provide a nice starting place for master transparency, 4:1 provides more color and higher ratios for a tougher sound full of character. Try using the Attack and Release controls to respond to tempo and feel of a track.
This control allows you to blend, or mix, the original uncompressed signal with the compressed signal providing another tool you can use to obtain your desired objective.
Monitor Input, Outputs and Gain Reduction levels.
- 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
- Proudly made in the USA in Seattle, Washington
zZounds is an authorized dealer of Chameleon Labs products.
Turn Unit On - VU Meter Light is ONCompression:
Insert compression circuit or bypassSide Chain:
Use Side Chain Input for triggeringCompression:
Soft or Hard knee compression typeDetection:
Peak or RMSHigh Pass Filter:
60, 90, 130 or 200 Hz high pass filter. When the HPF is engaged, the compressor doesn't affect frequencies below the cutoff. When the Side Chain input is engaged, the filter is applied to Side Chain detection signal.Threshold:
Applied between -15dB and +15dBAttack:
Attack time in milli seconds - .1 / .3 / 1 / 3 / 10 / 30Release:
Release time in seconds - .1 / .3 / .6 / 1.2 / 1.5Ratio:
Compression ratio selection 1.5 / 2 / 4 / 8 / 10Blend:
Full Dry equivalent to 0% compression, Full Wet equivalent to 100% compressionOutput Gain:
-60dB to +20dB Output Level controlVU Meter controls (L&R):
In - Input / Out - Output / GR - Gain ReductionInput (Female XLR):
50 kOhmSide Chain Input (Female XLR):
50 kOhmOutput (Male XLR):
200 OhmNoise Specification:
<-100dBu Input Terminated with 600 Ohm, compressor ON and Output Gain set to 0dBFrequency Response:
20Hz - 20kHz +/- 0.25dBHeadroom:
> 20dB output levelDynamic Range:
100 dB per AES17 StandardCommon Mode Rejection:
100Hz - 10kHz >90dBInput and Output Impedance:
>10kOhm / <50 OhmRed Input Gain:
Input OverloadRed Output Gain:
Output OverloadPower Supply:
100V - 240V (50/60Hz): Switch mode power supply, fully shielded 3-amp peak output capability, quiescent consumption 0.5 WattsMechanical:
1RU Steel enclosure, Aluminum front panel, Laser etched graphics, Milled aluminun knobs
- Weight, Dimensions, and Manufacturer Part Numbers
Manufacturer Part Number (MPN):