CSS3 Aural Properties

Aural properties defines the aural rendering of a document.

Aural Style Sheets

Aural style sheets are the part of CSS that uses a combination of speech synthesis and sound effects to make a web document more accessible to visually impaired and screen readers.

Aural presentation can be used:

• by blind people
• in the automobiles
• in devices like home entertainment
• industrial and medical documentation systems
• to help users learning to read or who have difficulty reading

When using aural properties, the canvas consists of a three-dimensional physical space (sound surrounds) and a temporal space (one may specify sounds before, during, and after other sounds). The CSS properties also allow you to vary the quality of synthesized speech (voice type, frequency, inflection, etc.).

An example of an aural style sheet:

Example :

h1, h2, h3, h4, h5, h6 {
    voice-family: male;
    stress: 20;
    richness: 90;
    cue-before: url("pop.au");
}
p {
    azimuth: center-left;
}
quotes {
    volume: x-soft;
}

This will direct the speech synthesizer to speak headers in a very rich male voice (a kind of "audio font").Before speaking the headers; a sound sample will be played from the given URL. 

Paragraphs will appear to come from front left (if the sound system is capable of spatial audio). And quotes will be very soft.