College Life Project

November 26, 2009


Audio visual project brief  for HN Unit Audio & Video 1 DF66 34


The object of this exercise is to concentrate on the audio layers within a movie. To do this you are going to work with some still images and imagine the sounds that you would hear within the scene. In this case use three cards from the Mars Attacks bubblegum card set.

Pick card scenes that are going to allow you a lot of scope to create a densely layered soundtrack. Remember there are three basic layers in a soundtrack

Sound Effects
Music
Dialogue

Insert your choice of cards into a word document and write about what you think would be heard within the scene. This becomes your plan for sourcing and editing your audio sample files

As usual, create a project folder to keep all your files in and then create a project in Premier Pro. Create three scenes on the timeline each lasting approximately 20 seconds. Include titles and credits. Export your final movie in DV AVI format.

marsAttacksSoundExercise2002

Digital Audio Technology 1

September 21, 2009


Some useful concepts to help you to understand the technology behind working with digital audio.

Pulse Code Modulation

Pulse-code modulation (PCM) is a digital representation of an analog signal where the magnitude of the signal is sampled regularly at uniform intervals, then quantized to a series of symbols in a numeric (usually binary) code

Sampling

In signal processing, sampling is the reduction of a continuous signal to a discrete signal.

A common example is the conversion of a sound wave (a continuous-time signal) to a sequence of samples (a discrete-time signal).

Sample rate

When it is necessary to capture audio covering the entire 20–20,000 Hz range of human hearing, such as when recording music or many types of acoustic events, audio waveforms are typically sampled at 44.1 kHz (CD), 48 kHz (professional audio), or 96kHz. The approximately double-rate requirement is a consequence of the Nyquist theorem.

Quantization

Quantization can be thought of as mapping a signal with a continuous set of sample values to a set of discrete values.

Or,  its a way of approximating a very large range of values by a relatively small (“finite”) set of (“values which can still take on continuous range”) discrete symbols or integer values.  For example binary code in a computer.

For digital audio both of these steps (sampling and quantizing) are performed in analog-to-digital converters (ADC) with the quantization level specified in bits. This is known as resolution or bit depth of the sample.

The resolution of the converter indicates the number of discrete values it can produce over the range of analog values. The values are usually stored electronically in binary form, so the resolution is usually expressed in bits. In consequence, the number of discrete values available, or “levels”, is usually a power of two.

For example, an ADC with a resolution of 8 bits can encode an analog input to one in 256 different levels, since 28 = 256. The values can represent the ranges from 0 to 255.

Quantization introduces digital noise!  This is in addition to the noise that exists in all analog electrical circuits.

The Signal to Noise Ratio (SNR) is a ratio of the signal power to the noise power corrupting the signal.

There is a relationship between quantization noise and SNR that has direct effect on the qulity of the audio sample.

Online Remixing

March 30, 2009


YourSpins is a site that lets you remix existing artists work.  It uses a multitrack mixer where you can adjust volume levels and change instruments or sound effects

On Line audio mixing

March 30, 2009


There are a growing number of sites that let you upload, edit and mix audio samples and then save them for others to hear, a couple of examples are

Jamglue which seems very active at the moment, you need to join to create a mix.

Splice which seems simpler to work but has less users and appears a bit out of date

Rhythm Basics

March 16, 2009


Try this site for an explanation of rhythm and tempo

http://www.hoerl.com/Music/music3_rhythm.html

Music Catch

March 9, 2009


Nice game, whats your highest score?

http://www.kongregate.com/games/Reflexive/music-catch

Check out the other music games on kongregate

Hobnox Audiotool

March 9, 2009


Produce your own electronic music with the Hobnox Audiotool. All in your browser.

http://www.hobnox.com/audiotool.1046.en.html

Monkey Machine online

March 9, 2009


Try out this online drum machine.

http://www.rinki.net/pekka/monkey/#


Spend some time trying this online sequencer

http://www.zefrank.com/sequencer/