Categories of effects

Hi, My name is Pamela García. I’m from Guatemala, Guatemala. I’m going to write a lesson about the effect categories, from Introduction to Musical Production, week three, of coursera.org.

The effects are divided on three cateories:

• Dynamic Effects
• Delay Effects
• Filter Effects

The Dynamic effects are related to the amplitud.  They help us to adjust the volume of our tracks, such as:

• Compressors:  reduces the volume of loud sound or amplifies quiet sounds.

• Limiters:  Compression and limiting are not different in process but in degree and perceived effect. A limiter is a compressor with a high ratio and, generally, a fast attack time.

• Expanders:  The expander is a compressor in reverse. There are two types of expander. In some, signals above the threshold remain at unity gain whereas signals below the threshold are reduced in gain, whereas in others the signal above the threshold also has the gain increased.

• Noise Gates:  attenuate signals above a threshold, noise gates attenuate signals which register below the threshold.

The Delay effects are related to the propagation.  They help us to adjust our sense of space in our tracks, such as:

• Reverbs:  is the persistence of sound in a particular space after the original sound is produced. A reverberation is created when a sound is produced in an enclosed space causing a large number of echoes to build up and then slowly decay as the sound is absorbed by the walls and air.

• Delays: it records an input signal to an audio storage medium, and then plays it back after a period of time.

• Phasers:  is an audio signal processing technique used to filter a signal by creating a series of peaks and troughs in the frequency spectrum. The position of the peaks and troughs is typically modulated so that they vary over time, creating a sweeping effect.

• Flangers:  is an audio effect produced by mixing two identical signals together, with one signal delayed by a small and gradually changing period, usually smaller than 20 milliseconds.

• Choruses:  it occurs when individual sounds with roughly the same timbre and nearly (but never exactly) the same pitch converge and are perceived as one.

The Filter effects are related to the timber of the sound.  They helps us to adjust the high and lows of our tracks, such as:

• High Pass Filter:  is an electronic filter that passes high-frequency signals but attenuates(reduces the amplitude of) signals with frequencies lower than the cutoff frequency. The actual amount of attenuation for each frequency varies from filter to filter.

• Low Pass Filter:  is an electronic filter that passes low-frequency signals and attenuates (reduces the amplitude of) signals with frequencies higher than the cutoff frequency. The actual amount of attenuation for each frequency varies from filter to filter.

• Band Pass Filter:  is a combination of a low-pass and a high-pass. is a device that passes frequencies within a certain range and rejects (attenuates) frequencies outside that range.

• Parametric EQ:  are multi-band variable equalizers which allow users to control the three primary parameters: amplitude, center frequency and bandwidth. The amplitude of each band can be controlled, and the center frequency can be shifted, and bandwidth ("Q") can be widened or narrowed. Parametric equalizers are capable of making much more precise adjustments to sound than other equalizers.

• Graphic EQ:  the input signal is sent to a bank of filters. Each filter passes the portion of the signal present in its own frequency range or band. The amplitude passed by each filter is adjusted using a slide control to boost or cut frequency components passed by that filter. The vertical position of each slider thus indicates the gain applied at that frequency band, so that the knobs resemble a graph of the equalizer's response plotted versus frequency.