Cause of audial equipnents in night
Answers
Audio-visual is, of course, a combination of two words: audio referring to that which we can hear, and visual referring to that which we can see. The basic frame of reference here limits our application of the term to a speaker and his audience, although they are not necessarily in the physical presence of one another, as in the case of a motion picture or television presentation.
The term "aids," used in reference to the speaker, rules out his physical presence (visual) and unrecorded voice (audio). These are the essential elements which make him a speaker, and therefore cannot aid him (his voice cannot aid his voice).
Further, the uncontrollable physical surroundings are not audio-visual aids in themselves, although they can have a definite audio or visual effect and should therefore be considered, if possible, when preparing a presentation. These include such things as distracting street noises (a hindrance) or a soundproofed room (an aid); or a beautiful mural behind the speaker (a distraction), purple and orange walls (a hindrance), or a paneled, modern meeting room with indirect lighting (an aid).
Handouts, especially maps, charts or tables, make good visual aids. The audience, particularly a large one, can get a finer appreciation of details which cannot be enlarged in a suitable manner. However, the audience is left in a position to continue studying such material, both before and after the speaker refers to it, and thus he cannot "control" its use.
We are left, then, with audio-visual aids which the speaker can control, and which are suitable for use with audiences of widely varying sizes.
Audio-Visual Aids
The term "audio-visual aids" is commonly misapplied. The aids themselves must be something either audible or visual, or both. The common types of audible aids are the spoken word, recognizable sound effects, and music. The most frequently used visual aids are people, pictures, cartoons, graphics, maps, the printed word, and three-dimensional models. When we talk about a motion picture projector or a blackboard, we are talking about the means of presenting the aids, and not the aids themselves.
Audio-visual materials can be divided into those which present the aids in their original form, and those which reproduce the original form.
In the following paragraphs, we will briefly define the most common means of display which make sights and sounds useable in the speaker-audience situation outlined above. They will be discussed in further detail in later chapters.
Visual Aid Display Equipment
Animation. Movement may be given to different types of visual aids. The materials necessary to do so fall in this section, but since they are usually improvised they cannot be specifically defined. Examples are given later in this report.
Blackboard. Black, green or other colored slate or composition board, or a specially painted surface which will "take" erasable white or colored chalk.
Bulletin Board. Flat board of cork, composition or other wood or material to which visual aids may be attached with pins, tacks or staples.
Easel or A-frame. Any type of frame which will hold flat-surfaced visual aids of any given size; characterized by the artist's easel, which is similar in structure to the letter "A," with a third leg used as a brace.
Feltboard. Any stiff, flat board covered with wool, felt or flannel. A variety of visual aids, usually cutouts of objects or strips of cardboard lettered with key words, with sandpaper or other abrasive backing, will adhere to the board. The same effect can be achieved by backing the visual aids with two-sided cellophane or masking tape, and covering the board with a piece of acetate; or by using strips of Velcro.
Flash Cards. A series of stiff cards, usually small enough to be held in the hands, each of which is imprinted with one or more key words.
Flip Charts. A series of visual aids on flexible paper, fastened together at the top and mounted on a frame in such a manner that they can be flipped or folded back. The frame usually resembles a football goal post, with the charts fastened to the crosspiece.