2 – Introducing the TASCAM
Used on a vocal track, this setting will compress only hot peaks in the voice, while gating out the room sounds, mike stand sounds, and breath noises in the track. Precisely what gets compressed and gated is a function of the compressor and gate threshold settings.
The graph below shows a dynamic expander. In this application, the gate threshold and ratio are set to gently expand the program material at a 1 to 1.5 ratio. The compressor ratio is set to 1 to 1. The setting is useful for repairing
COMPRESSOR
THRESHOLD
GATE THRESHOLD
LOUDER
OUTPUT |
|
LEVEL | 1 TO 1.5 EXPANSION RATIO |
|
LOUDER
INPUT LEVEL
Hard Knee/Soft Knee
The graphs shown above have what are described as “hard knees” in their gain curves. This means that as the signal passes through the threshold, the gain reduction it receives will begin abruptly. In settings where the compression or expansion ratios have high values, the abrupt change can be heard and often sounds artificial.
To make it possible to create settings where the dynamic effects are more natural sounding, the
COMPRESSOR THRESHOLD
SOFT KNEES
KNEE = 100
GATE THRESHOLD
OUTPUT
LEVEL
Attack and Release Times
The attack time of a compressor is how long it takes for the compressor to react once the input level has met or exceeded the threshold level. With a fast attack time, the signal is brought under control almost immediately, whereas a slower attack time will allow the start of
a transient or a percussive sound to pass through uncompressed before the processor begins to react.
For sounds without percussive attacks (voices, synth pads, etc.), a fairly short attack time is usually used to ensure even compression. For instruments with percussive attacks (drums and guitars, for example), a slower attack time is typically used to preserve the attack transients and, hence, the characteristic nature of the instruments.
The illustration below shows the effect of various the attack times.
UNCOMPRESSED INPUT | COMPRESSED | COMPRESSED |
| 1 mSEC ATTACK | 10 mSEC ATTACK |
The release time of a compressor is the time it takes for the gain to return to normal after the input level drops below the threshold. A fast release time is used on rapidly varying signals to avoid affecting subsequent transients. However, setting too quick a release time can cause undesirable artifacts with some signals. On the other hand, while slower release times can give a smoother effect, if the release time is too long, the compressor will not accurately track level changes in the input. Slow release times may also result in audible level changes known as “pumping.”
INPUT LEVEL
12 TASCAM