Diegetic sound is sound that comes from the setting of the film. Non-diegetic sound is sound that comes from our world, such as the soundtrack or scoring. Diegetic sound could include the voices of characters, utensils clattering in the background, or music coming from a piano being played on-screen. 

It's important to understand diegetic sound because it's what makes the world of your film feel real. Knowing how to use diegetic and non-diegetic sound in film will set your film in a specific time and place that the audience can recognize.

While non-diegetic sounds, like narration or the score, can help stylize your film and help your audience feel the emotion of the scenes you are showing, diegetic sound is what truly creates a film.

It's also important to understand that diegetic sound doesn't necessarily have to be captured live. Sometimes, you need to add sound effects or clean up your sound design in post-production. That can also include automated dialog replacement lines after the fact.

This all still counts as diegetic sound, since it's intended to be a part of the actual scene rather than the framing of the scene after the fact for the audience.

Essentially, if a character in the scene would be able to hear a sound (assuming that they aren't Deaf or hearing-impaired), then it's probably part of the scene's diegetic sound.

Ambient sound (AKA ambient audio, ambience, atmosphere, atmos or background noise) means the background sounds which are present in a scene or location. Common ambient sounds include wind, water, birds, crowds, office noises, traffic, etc.

Ambient sound is very important in video and film work. It performs a number of functions including:

• Providing audio continuity between shots.

• Preventing an unnatural silence when no other sound is present.

• Establishing or reinforcing the mood.

Synchronous sound represents the matching of sound to the movements that are taking place on the screen. For example, if you see a person moving across the screen, perhaps walking in water, then you might hear footsteps and you could also hear splashes as each step is taken.

These sounds would align with the appearance of each step, and so with each splash from the foot, the water sound would equally be aligned. Synchronous sounds correspond with what’s happening visibly on the screen.

ASYNCHRONOUS SOUND

Unlike synchronous sound, asynchronous sounds in film do not necessarily correspond with what you see on the film screen. Asynchronous sounds in film can still add value to the action being performed, but it’s likely an action that already took place (such as a previous sound) or the sound of an action that is about to occur on the screen.

For example, asynchronous sounds, although they are not precisely synchronized with the actions currently occurring on the screen, add value to the story and help to create a stronger sense of realism.

A film soundtrack is more a selection of songs chosen to be featured in a film. In most cases they are existing tracks that have been licensed by the film's producers; in rarer cases films feature original songs, written especially with the film's story in mind. 

Film scores are non-diegetic and cannot be heard by the characters on screen.

Sometimes, however, films will feature diegetic music. If a character is listening to music playing on a radio or if characters are singing or playing a musical instrument, then that music is diegetic.

Incidental music is music in a play, television program, radio program, video game, or some other presentation form that is not primarily musical. The term is less frequently applied to film music, with such music being referred to instead as the film score or soundtrack.

Incidental music is often background music, and is intended to add atmosphere to the action. It may take the form of something as simple as a low, ominous tone suggesting an impending startling event or to enhance the depiction of a story-advancing sequence. It may also include pieces such as overtures, music played during scene changes, or at the end of an act, immediately preceding an interlude, as was customary with several nineteenth-century plays. It may also be required in plays that have musicians performing on-stage.

A theme song is a work that represents the performance and is often played at the beginning or end of the performance. Elements of the theme may be incorporated into other incidental music used during the performance. In films, theme songs are often played during credit rolls. A love theme is a special theme song (often in various modified forms) that accompanies romantic scenes involving the protagonists of a performance.

Theme songs are among the works of incidental music that are most commonly released independently of the performance for which they were written, and occasionally become major successes in their own right.

A sound effect or combination of sound effects that are associated with a particular character, setting, situation or idea through the film. The sound motifs condition the audience emotionally for the intervention, arrival, or actions of a particular character. 

Foley is the word used to describe replacement sounds recorded in post-production. 

Foley artists can also enhance or replace an original sound - if a character’s footsteps were not loud enough they might record the sound of their own footsteps and have that audio inserted into the film instead. 

A sound effect is any sound, other than speech or music, which has been recorded specifically for the film.

Sound effects are usually tied to specific actions on-screen and recorded during post-production to enhance a scene.

A director might, for example, ask their sound designer to record high impact punching sounds to make a fist fight feel more exciting.

Voice-over (also known as off-camera or off-stage commentary) is a production technique where a voice—that is not part of the narrative (non-diegetic)—is used in a radio, television production, filmmaking, theatre, or other presentations. 

Mode of Address This is the tone and the written or spoken style of the media text and the way in which it communicates with the target audience 

Informal

Some texts for example magazines aimed at young teenage woman, adopt an informal register. They use slang, colloquial vocabulary and the personal pronoun to engage their target audience adn make them feel as if they are talking directly to them. The audience then feel as if they are part of the seemingly exclusive magazine.

Formal

Other texts, for example quality newspapers, will adopt a more formal style with more ocmplex vocabulary and writing style. This suggests that the target audience are more serious and sophisticated and want more detailed information. News anchors combine a formal mode of address with a serious code of expression, this encourages the audience to trust them and believe what they have to say.

This is where the subject of the text communicates directly with the audience.

Television presentners of a live television show- The effect is toi make the audience feel involved with the programme; it is as if they are talking directly to us at home.

News anchor engage in direct mode of address as they are dealing with serious and important matters.

Magazine cover models and celebrities often look directly out of the magazines, engaging seemingly in direct eye contact with the reader. Theyu draw the audience into the magazine, persuading us to purchase the text.

The term dialogue simply means the words that are spoken by the characters on screen.

The amount of dialogue in any given film can vary. An action film may have very little spoken dialogue but a character based drama may have a lot.

For film-makers it is important that dialogue is always well recorded and clearly audible.

It’s also important to never used dialogue if the story information being discussed can be shown visually.

This is often used at the start of a new scene, the music will come in quietly and increase in volume.

This is often used at the end of a new scene, the music will come slowly decrease in volume.

A sound bridge is an editing technique used to transition from one scene to another through sound. Sound bridges, also called an audio bridges, allow filmmakers to transition in or out of a scene by "bridging the gap" with audio. 

This is a technique used in music videos where the video clips are edited to match the beat of a song. This can also be used in other films/ tv programmes but should be used carefully.

Reverberation is created when a sound or signal is reflected causing numerous reflections to build up and then decay as the sound is absorbed by the surfaces of objects in the space – which could include furniture, people, and air 

Reverb is the same concept as an echo but with a smaller reflection time that often comes back within a second and conflates with the sound that hasn’t finished yet.  For example, If I were to say, “I would like to hear my echo,” and applied an echo effect through some software, I might say the entire sentence and then hear the entire sentence back.  However, if I said the same thing and applied a reverb effect, you could start hearing the effect before you get to the second word of the sentence.  This replicates what it sounds like to hear reflections of sounds from rooms with hard walls.  

Reverberation is created when a sound or signal is reflected causing numerous reflections to build up and then decay as the sound is absorbed by the surfaces of objects in the space – which could include furniture, people, and air 

The term distortion usually refers to a deviation from the original perfect form. In sound contexts this is a deviation from the perfect, desired sound curve. We recognize distortion from the bad speakers at drive-through restaurants or at bingo halls. 

Echo effects are one type of audio effect based on delaying a signal over time. In this case, listeners perceive an audible repetition of a signal after some duration of time. Listeners perceive distinct echoes when the time delay is relatively long.