The Noise command lets you generate random noise in a variety of colors. (Traditionally, color is used to describethe spectral composition of noise. Each color has its own characteristics.) Generating noise is useful for creating soothing sounds like waterfalls (perfect for use with the Binaural Auto-Panner function of Adobe Audition) and for generating signals that can be used to check out the frequency response of a speaker, microphone, or other audiosystem component.
- Place the cursor where you want to insert the noise. Or, if you want to replace part of the existing waveform, select the desired range of audio data.
- Choose Effects > Generate > Noise.
- Set options as desired, and click OK.
Specifies a color for the noise:
- Brown noise - Has a spectral frequency of 1/f2, which means, in layman’s terms, that the noise has much more low-frequency content. Its sounds are thunder- and waterfall-like. Brown noise is so called because, when viewed, the wave follows a Brownian motion curve. That is, the next sample in the waveform is equal to the previous sample, plus a small random amount. When graphed, this waveform looks like a mountain range.
- Pink noise - Has a spectral frequency of 1/f and is found mostly in nature. It is the most natural sounding of the noises. By equalizing the sounds, you can generate rainfall, waterfalls, wind, rushing river, and other natural sounds. Pink noise is exactly between brown and white noise (hence, some people used to call it tan noise). It is neither random nor predictable; it is fractal-like when viewed. When zoomed in, the pattern looks identical to when zoomed
out, except at a lower amplitude.
- White noise - Has a spectral frequency of 1, meaning that equal proportions of all frequencies are present. Because the human ear is more susceptible to high frequencies, white noise sounds very hissy. Adobe Audition generates white noise by choosing random values for each sample.
Specifies a style for the noise:
- Spatial Stereo - Generates noise by using three unique noise sources and spatially encoding them to seem as if one comes from the left, one from the center, and one from the right. When you listen to the result with stereo headphones, your mind perceives sound coming from all around. To specify the distance from center of the left and right noise sources, enter a delay value in microseconds. About 900 to 1000 microseconds correspond to the maximum delay perceivable. A delay of zero is identical to monaural noise, where left and right channels are the same.
- Independent Channels - Generates noise by using two unique noise sources, one for each channel. The left channel’s noise is completely independent of the right channel’s noise.
- Mono - Generates noise by using a single noise source, with the left and right channels set equally to that source.
- Inverse - Generates noise by using a single noise source (similar to the Mono option). However, the left channel’s noise is exactly inverse of the right channel’s noise. When you listen to the result with stereo headphones, your mind perceives sound coming from within your head instead of from somewhere externally.
Specifies the intensity of the noise on a scale of 2 to 40. At higher intensities, the noise becomes more erratic and sounds harsher and louder.
Adds a constant DC (Direct Current) amplitude to the tone, centering the waveform by shifting it up or down by the specified percentage.
Choose Effects > Generate > Tones to create a simple waveform using several amplitude‑ and frequency‑related settings. Generated tones are great starting points for sound effects.
Transitions tones from settings on Start tab to those on End tab. (Waveform remains constant.)
Modulates pitch of the base frequency over a user‑defined range. For example, a 100 Hz setting modulates the original frequency from 50 Hz below to 50 Hz above.
Specifies how many times per second the frequency modulates, producing a warbling, vibrato effect.
Choose one of the following:
- Sine and Inverse Sine produce the fundamental frequency. A Type setting of 1.00 produces pure tones; lower settings produce more square waves; higher settings more triangular.
- Triangle/Sawtooth produces a true triangle waveform with only odd harmonics at a Type setting of 50%. Settings above and below that percentage produce Sawtooth waveforms with both odd and even harmonics.
- Square produces only odd harmonics. A true square wave occurs with a Type setting of 50%. Settings above and below adjust the duty cycle of the waveform between a flat peak at 100% and a flat trough at 0%. (The outer extremes produce only an audible click.)
Adds up to five overtones to the fundamental frequency (Base Frequency). Below the sliders, enter either a specific frequency for each overtone, or specify a multiplier of the fundamental. Then, use the Amplitude sliders to mix overtones in proportion to one another.
Specifies the length of the generated tone in the format currently specified for the time ruler. Right-click the numbers to choose a separate time format for Generate Tones.
Start Phase At
Specifies the starting location in the waveform cycle. If set to 0°, waves will start at the zero-crossing point. If set to 90°, the wave will start at full amplitude (generating a noticeable click).
2nd Channel Phase Difference
Adjusts the relative phase of stereo channels. A value of zero places the channels completely in phase and 180 places them completely out of phase.
Dynamically changes the relative phase between the two channels of a stereo audio file over time. For example, if you enter 1 Hz, the phase difference will cycle through 360° each second.
Adds a Direct Current offset, shifting the center of the waveform up or down by the specified percentage. Use this adjustment to calibrate audio hardware or simulate hardware-induced offset.
With Selected Audio
Choose from the following:
- Replace: Swaps existing audio with generated tones.
- Modulate: Ring modulates, or multiplies, existing audio with current tone settings. This option is great for adding special effects.
- Demodulate: Ring demodulates existing audio with current tone settings. Use this option to create unique effects or revert audio previously processed with the Modulate option to its original state.
- Overlap: Mixes the generated tones with existing audio.
Adobe Audition is a powerful application for recording and mixing audio, podcasting, and sound effect design.