Available as an assembled Module and as a DIY project.
This Module is currently available.
Outstanding VCA compressor with multi-channel operation capability and user configurable sidechain filters.
Specifications:
CONTROL RANGES:
Threshold : -30dBu to +20dBu
Attack : 100uS to 75ms (Also active in A1 or A2 Recovery mode).
Recovery : 75mS to 3S or A1: 50ms/5S or A2: 100mS/2S
Ratio : 0 to Limit (>10:1)
Gain makeup : -6dB to +18dB
Dry/Wet : Fully Dry (Uncompressed) through to fully Wet (Compressed).
Sidechain Filter switch : OUT or low pass filters F1 or F2. These can be user defined by jumpers.
Optional Sidechain and Dry path insert points.
Hard/Soft switch.
Feed forward/Feedback switch.
“L” switch providing “Sidechain Listen” facility or multichannel linking.
“Master “LED illuminated when a module is the “Master” of a group of modules.
Audio meter range : Signal present to +18dBu
Gain Reduction meter range : 1.5dB to 22dB
FREQUENCY RESPONSE:
+/- 0.5dB 20Hz to 20 kHz with no compression.
NOISE:
Measured true RMS, 20Hz to 20 kHz
Compressor OUT: -98dBu
Compressor IN (unity gain) -88dBu (with THAT4301 VCA).
With the BYPASS card option there is no noise contribution when the compressor is switched OUT.
THD&N:
Better than 0.05% at 1 kHz and +10dBu input with compressor OUT.
With the compressor IN the THD&N is similar with moderate degrees of compression but will increase depending on control settings and signal frequency.
MAXIMUM LEVELS:
Supply rails +/-16V
Maximum input level: +27dBu
Maximum output level (Compressor OUT): +27dBu into 200k load, +25dBu into 600ohm load.
Internal operating level -6dB. This is also the level at unbalanced insert points.
IMPEDANCES:
Input impedance (balanced): 24k ohms.
Output impedance (balanced): 75 ohms.
Unbalanced SIDECHAIN insert input impedance: 50k ohms.
Unbalanced SIDECHAIN insert output impedance: less than 75 ohms.
Unbalanced optional DRY insert input impedance: 50k ohms.
Unbalanced optional DRY insert output impedance: less than 75 ohms.
SLEW RATE:
Compressor OUT better than 7V/uS.
Compressor IN 2V/uS