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Definition
20-80 Hz
First and second octaves. Power, boom and fullness. Lowest notes of the piano, tuba, bass. Sounds in these octaves need not occur often to maintain a sense of fullness. |
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80-320 Hz
3rd and 4th octaves. Most lower notes of various instruments. Establish a balance in musical structure. Too many in this range makes it sound boomy. Too few make it thin. Upper bass frequencies provide a foundation. Bass control on home stereo systems. |
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Term
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Definition
320-2,560 Hz
5th, 6th and 7th octaves. Gives sound intensity. Contains the fundamental and the rich lower harmonics and overtones of most sound sources. Too much 6th octave however is heard as a hornlike quality. Too much 7th is tinny. Extended listening to midrange sounds can be fatiguing. |
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Definition
2,560-5,120 Hz
8th octave. We are most sensitive to frequencies in the 8th octave. The lower part of this range (3,000-3,500Hz) if emphasized, improve speech. The upper part (above 3,500 Hz) contains pitches that give sound definition, clarity and realism. Sounds in this region (also up to 6,000 Hz) are perceived as being nearby so it is also known as the presence range. |
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Definition
5,120-20,000 Hz
9th and 10th octaves. Only 2 percent of the total power output of the sound frequency spectrum. But they give the sound qualities of brilliance and sparkle. Increasing at 5,000 Hz gives the impression that there has been an increase in loudness of midrange frequencies. Reducing around 5,000 Hz makes it sound distant. Too much emphasis above 6,000 Hz makes sound hissy and brings out electronic and record noise. Too little above 6,000 Hz dulls sound. |
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Term
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Definition
| Narrowcasting. Know your audience. Know how to reach them. This is more important than the product. |
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Definition
Age 18-20
Age 21-24
Age 25-34
Age 35-44
Age 45-49
Age 50-54
Age 55-64
Age 65-74
Age 75+
Makes generalizations about groups of people. |
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Term
| Physical-acoustic wave properties |
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Definition
Sound is a longitudinal wave. Compression, rarefaction. The molecules don't move at the speed of sound. They wave does, pushing the molecules against each other.
A wave has 3 parts
Dynamic Sound Envelope
Attack is usually between 5 and 25 milliseconds (1000ms per second). This is taking at rest air molecules and exciting them. We usually see a fairly strong attack.
Sustain is the body of the sound. It is the sound as we recognize it. There is internal dynamics within sustain. It is when the harmonics and overtones within the sound. It loses energy but becomes more colorful.
Decay is when the wave has lost 60% of it’s energy. |
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Term
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Definition
These characteristics allow one waveform to be distinguished from another. The most fundamental are amplitude and frequency.
Amplitude- distance above or below centerline of a waveform. Greater the distance from the centerline, the more intense the pressure variation, electrical signal level or physical displacement will be within a medium (air).
Frequency- the rate at which an acoustic generator, electrical signal or vibrating mass repeats within a cycle of positive and negative amplitude. As the rate of vibration increases, so does the pitch and frequency. Hz is the measure of cycles in one second.
Velocity- at 68 degrees sound travels approximately 1130 ft/sec. Sound's speed is temperature dependent and increases at a rate of 1.1 ft/sec for each Fahrenheit degree increase in temperature.
Wavelength= Velocity/Frequency (W=V/f). < my question. does temperature change the frequency of a sound and therefore its pitch? |
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Term
| Waveform Characteristics Pt. 2 |
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Definition
Phase- Whenever 2 or more waveforms arrive at a single location out of phase (sync), their relative signal levels will be added together to create a combined amplitude level at that one point in time. Whenever 2 waveforms having the same frequency, shape, and peak amplitude are completely in phase (no time difference) the newly combined waveform will have the same frequency, phase and shape but will double in amplitude. If the same 2 waves are combined completely out of phase (phase difference of 180 degrees) they will cancel each other out which results in zero amplitude.
Harmonic content- the factor that helps us differentiate between instrumental "voicings" is the presence of frequencies (called partials) that exist in addition to the fundamental pitch that's being played. Partials which are higher than the fundamental frequency are called upper partials or overtones. Overtone frequencies that are whole-number multiples of the fundamental frequency are called harmonics.
Envelope- Characteristic variations in level that occur in time over the duration of a played note. |
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Term
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Definition
| Square waves, triangle, waves and sawtooth waves. Contain a consistent harmonic structure. One cycle of a square wave looks exactly like the next. They are symmetrical about the zero line. |
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Definition
| Don't necessarily repeat and often are not symmetrical about the zero line. Created by any naturally occurring sound (music or speech). While complex waves are not repetitive in nature, all sounds can be mathematically broken down as being an ever-changing combination of individual sine wave. |
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Term
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Definition
our ears do not hear linearly. We don’t hear all frequencies the same.
1. Our ears are most sensitive to midrange frequencies relative to bass and treble frequencies.
2. As volume increases bass and treble frequencies appear to get louder relative to midrange frequencies. |
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Term
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Definition
| In order for the desired frequency bandwidth to be faithfully encoded in the digital domain, the selected sample rate must be at least twice as high as the highest frequency to be recorded. |
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Term
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Definition
| Used to translate the voltage levels of a continuous analog signal into binary digits (bits). th e most common binary word length for audio is 16-bit (16 0s and 1s). There are also profession systems with 20 and 24 bit resolution. |
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Term
| Least Significant Bit (LSB) |
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Definition
| The final and smallest numeric value within a digital word. This is where errors are most likely to accumulate with lower bit-depth. |
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Definition
| Mic, input, gain, fader, master fader, output, computer. |
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Term
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Definition
| Computer, output, master fader, track fader, gain, mic input, mic. |
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Term
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Definition
| Input and output are equal. |
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Term
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Definition
| Operating signal strength for all electronics. Comes from telephone company. |
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Term
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Definition
| A lower level signal that needs to be boosted to line level by gain stage electronics. |
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Term
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Definition
| Gain is active and the faders are passive. |
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Term
| Three systems found in production audio consoles |
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Definition
Input- brings the signal to line level.
Output
Monitor |
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Term
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Definition
| 1/10th of a bell. Expresses differences in intensities between two levels. |
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Term
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Definition
Negative infinity is the noise floor. Other side of it is distortion, clip, saturation point or overload.
The area above 0vu and below clip is called head room. The greater the signal to noise ratio the greater the fidelity. You can have different degrees of head room. The only way to tell when you have clipped is to physically hear distortion (you can see the red but not be distorting). The peak meter should light up 10-15% of the time if you have exhausted the circuit. |
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Term
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Definition
| From unity to where the signal peaks. -15vu in digital to clipping and 0vu to clipping in analog. |
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Term
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Definition
| 55 parts signal to 1 parts noise. |
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Term
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Definition
Analog is forgiving (especially when it comes to clip). Analog sounds like film looks. If manipulated, you get generation loss.
Digital is an abstraction. Digital is not forgiving and is unusable once it distorts. Digital distortion never sounds good. Redbook audio (consumer standards) sounds like video looks. Digital is a good storage medium, non destructive editing, ultimate manipulation of the data, can make clones easily. In analog you get generation loss from this. Analog is the perfect acquisition format and digital is the best storage format. |
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Term
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Definition
| Displays the signal level strength. Absolute is digital and absolute is analog. |
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