Specifications
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Sample Rate
The rate at which the data in an analog audio signal is measured to form a digital representation of the
sound wave. In a computer, it is impossible to work with an infinite amount of data, which is what would
be required if a continuous wave were to be represented digitally inside the machine, so at every possible
instant in time we would have the measured value of the waveform at that instant. For this reason, it is
necessary to sample sound wave data. Sampling means breaking a wave at various intervals and using
a single measured value to represent all the values in each interval. By dividing the waveform like this,
one second of audio can now be represented by a finite number of values. The sample rate is the
number of measurements taken per one second of audio.
SayTime
Accessory software that allows Simian to say the time of day. SayTime is customizable for your own
voices and the time statement can include a station header (WKRP News time is…). There is also a
macro command with the format SAYTIME.
SayTemp
Accessory software that allows Simian to actually speak the current temperature. SayTemp is
customizable for your own voices and the time statement can include a header (Current temperature in
Cincinnati is…).
Sectone
“Sectone” or “Sec Tone” is a broadcast term related to the use of magnetic tape cartridges or carts.
Sectone is short for secondary tone and indicates the point, or cue, near the end of a song where it’s OK
to begin playing the next event. It is the starting point of the “Segue”.
Segue
A transition between two audio segments. The segue length is the time during which two consecutive
audio segments overlap or are played simultaneously. The sectone setting determines the segue length.
Sound
When objects vibrate or collide, they produce an excitation of the molecules in the surrounding air. If the
resulting vibrations are within a certain frequency range, we sense it in our eardrums as a change in air
pressure. Our brain then interprets this as sound. Sound waves move in all directions outward from the
original disturbance like the ripples created from a stone dropped in a pool of water.
When sound is recorded through a microphone, the changes in air pressure cause the microphone's
diaphragm to move in a similar way to that of the eardrum. These minute movements are then converted
into changes in electrical signals. All sound cards generally produce sound in this way, only in reverse.
They create or play back sound waves. The changes in voltage are then amplified, causing the
loudspeaker to vibrate, which in turn cause air pressure changes which are interpreted by humans as
sound.
The frequency range of vibrations felt by humans is between 20 and 20,000 cycles per second. This
gives us the sensation of pitch, harmonics, tone and overtones. Frequency is measured in Hertz (Hz).
One Hertz is one wave repetition or cycle per second.
Sound Card
The expansion board in your PC that enables it to play or record digital audio files. The modern PC
sound card contains several hardware systems relating to the production and capture of audio. The main
systems capture and replay digital audio. Sound waves from these systems are produced by playing a
digitized (or sampled) sound.
The digital audio section of a sound card consists of a matched pair of digital-to-analogue (DAC) and
analogue-to-digital (ADC) converters and a programmable sample rate generator. The computer reads
the sample data to or from the converters.