-20 oct BANDWIDTH 5 10 1 0.5 2 ATTACK ms Hz 3.15k 20k FREQUENCY PEQ 20 640 Auto 2s 1s 10 5 RELEASE 25 125 Auto 500 ms 25 50 500 250 50 125 n:1 100 1 1.
IMPORTANT SAFETY INSTRUCTIONS 1. Read these instructions. 2. Keep these instructions. 3. Heed all warnings. 4. Follow all instructions. 5. Do not use this apparatus near water. 6. Clean only with a dry cloth. 7. Do not block any ventilation openings. Install in accordance with manufacturer’s instructions. 8. Do not install near any heat sources such as radiators, registers, stoves, or other apparatus (including amplifiers) that produce heat. 9.
INSTRUCTIONS DE SÉCURITÉ 1. Lisez ces instructions. 2. Gardez précieusement ces instructions. 3. Respectez les avertissements. 4. Suivez toutes les instructions. 5. Ne pas utiliser près d’une source d’eau. 6. Ne nettoyer qu’avec un chiffon doux. 7. N’obstruer aucune évacuation d’air. Effectuez l’installation en suivant les instructions du fabricant. 8. Ne pas disposer près d’une source de chaleur, c-à-d tout appareil produisant de la chaleur sans exception. 9. Ne pas modifier le cordon d’alimentation.
OPERATORS MANUAL C4 QUAD COMPRESSOR / LIMITER -12 -6 -3 -1 TH 18 12 8 2 Reduction dB 0 4 2 1 1 LINK MASTER -20 dBr -10 0 -30 1.5 +10 -40 +20 1 dBu COMP THRESHOLD 250 25 500 ms -6 10 -12 RATIO 100 50 n:1 5 125 500 25 ms Auto RELEASE -30 Hard Soft KNEE 1 125 dBu +22 +10 1 COMP THRESHOLD 24 dB 250 25 500 ms 125 Headroom 4 2 10 -12 500 +6 oct 10 BANDWIDTH 20 Hz 20k FREQUENCY PEQ dB GAIN 0.
Dynamics 101 Revisited Compression A compressor, when the input signal reaches the level set by the threshold control, begins turning down the signal by an amount set by the ratio control. Modern compressors make the loud signals quieter, but do not make the quiet parts louder. (However, by keeping the loud signals under control, you can turn up the output level, which will make the quiet parts louder along with the rest of the signal.
Dynamic EQ Dynamic EQ differs from the forms of compression listed above in that it dynamically controls the boost/cut of a parametric filter rather than broadband frequency gain. The basic dynamic EQ uses a bandpass filter in the side-chain with variable center frequency and bandwidth. The side-chain detector is sensitive only to the passband frequencies.
Dynamic EQ Applications Auto-Correct Microphone Proximity Effect Use Dynamic EQ to automatically correct for timbre changes due to the low frequency boost caused by the proximity effect of cardioid microphones (see Figure 6), which occurs when a singer/speaker does not remain a consistent distance from the microphone. Two opposite applications share this problem: 1.
Peak Limiting A limiter is just a compressor with a really high ratio, right? Well…not exactly. Although the two devices use similar terminology (Threshold, Attack, Release, and so on), they serve two completely different purposes and therefore operate in different manners. Fundamentally, a compressor uses an rms detector to keep the average level of a signal under control, while a limiter uses a peak detector to act on the instantaneous level of the signal. Compare Figure 2 to Figure 7.
Making Connections Front Panel Controls The C4 features auto balanced/unbalanced XLR and ¼" TRS input and output jacks, permitting connection to virtually any mixing console. Side-chain inputs are also auto balanced/unbalanced, on ¼" TRS only. Dynamics processors typically connect using a mixing console’s insert points (send/return), although they can be used in-line, such as when compressing or limiting an overall mix, for example.
MASTER / SLAVE Stereo Link 1 2 3 SLAVE MASTER LINK MASTER When channels are Linked • Bypassing the Master channel does not automatically bypass the Slave channel. Channel ACTIVE / BYPASS switches are the only controls which do not follow the Master channel, making it possible to bypass each channel individually. 4 LINK SLAVE The MASTER / SLAVE switches link channels 1 & 2, or channels 3 & 4 for stereo operation.
COMPressor THRESHOLD, RATIO and GAIN -20 -10 -30 0 +10 -40 0 2 1.5 +20 1 dBu COMP THRESHOLD n:1 ATTACK, RELEASE and KNEE 100 5 -6 +6 50 250 10 -12 +12 25 500 RATIO dB GAIN ms 125 500 1s 50 ATTACK 2s 25 ms RELEASE Auto Hard Soft KNEE Auto The threshold, like crossing through a doorway, is the beginning point of gain adjustment. When the input signal is below the threshold, a compressor acts like a straight wire.
SIDE-CHAIN Parametric EQ +10 +9 +8 2 +7 1 +6 0 640 5 125 3.15k +5 +4 O u t p u t d B u 0.5 Threshold +3 +2 +1 Soft -1 -2 20 Hz 20k FREQUENCY PEQ -12 dB +12 GAIN The Side-chain PEQ filter operates in one of two ways, depending on whether the channel is operating in Compressor mode or Dynamic EQ mode. -3 -4 10 dB span -5 10 BANDWIDTH Hard 0 oct -6 -7 -8 -9 -10 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +10 Input dBu Figure 15.
LIMIT THRESHOLD and Headroom Meter LIMIT 3 -20 -10 -30 6 0 12 +10 -40 dBu +22 Tips and Tricks -20 LIMIT THRESHOLD Headroom In addition to the Compressor / De-esser, each channel of the C4 features an independent, brick-wall Limiter with an instantaneous attack time, fixed 25 ms hold time and a fixed 6 dB/second release rate. The C4’s limiter uses oversampling in order to ensure high frequency transients are properly detected and acted upon.
ATTACK RELEASE RATIO KNEE Vocals Medium to Fast Medium to Slow 2:1 to 4:1 Soft Clicky Bass Fast Fast 4:1 or higher Hard Mushy Bass Medium to Slow Medium to Slow 4:1 Hard Slow 4:1 or higher (more sustain) Hard Raging Electric Guitar Fast Acoustic Guitar Medium to Slow Medium to Slow 4:1 Medium Brassy Horns Fast Fast 5:1 or higher Hard Drums (kick, snare) Fast Fast 4:1 Hard Drums (cymbals) Fast Slow 2:1 to 10:1 Hard Table 1.
-20 -20 n:1 2 -20 BANDWIDTH 10 0.5 oct 5 1 2 ATTACK 20k 3.15k ms Hz 20k 3.15k FREQUENCY PEQ 20 640 Auto 2s 1s 10 5 RELEASE 25 125 Auto 500 ms 25 50 500 250 50 125 n:1 2 100 1 1.
