Understanding the method and principles of sound design and production

Unit 73: Sound for Computer Games

Exorcise 1

Researching Sound File Formats

The way in which a sound is formatted is a key part of getting sound to work how you want on a technical level, such as whether you want it to be mono, stereo or surround sound, and the overall quality of the sound as some of the file types will compress it. File formats that do not compress the sound tend to require greater hardware to run as they can take up massive amounts of memory making , often in games these file types are found in games for higher end consoles and certainly in triple A titles as they seek to generate the greatest possible sense of immersion. These file types involve things such as WAVs, AIFFs, AUs, SMPs and VOCs. These uncompressed file types are near perfect ways of conveying the sounds as they were recorded, losing no large amount of quality. Compressed file formats however require far less memory due to them being compressed and require less powerful hardware to run, and are often used in things like indie games as the people making them may not have the resources available for the higher quality of uncompressed file types. the largest draw back is the noticeable decrease in quality when using a compressed file type making the overall product seem to be a slightly more inferior product to those it may have to compete with in its market. Compressed file types include things like MP3s, RAs and VOXs.

Audio Sampling

1. How Resolution and Bit Depth Can Constrain a File Size

The bit depth of a file directly links to its resolution. The bit depth refers to the bits per sample, examples of where most people will experience is in things such as a CD at 16 bits per sample or Blu Ray disks at 24 bits per sample. Bit depth is mostly affects noise levels arising from quantization errrors. Bit depth however hardly ever comes into the context of lossy compression files like MP3s.

2. Key Word Definitions

Sample Rate - digital signal processing. The number of times an analog signal is measured (sampled) per second. The unit of sample rate is "samplesper second". This is often expressed in kiloHertz (kHz). For example, "CD quality" sound has a sample rate of 44 kHz.

Mono - sound played one way through all speakers with the effect ending up being that the same sound come from all sources

Stereo - sound that is directed through two or more speakers so that it seems to surround the listener and to come from more than one source; stereophonic sound.

Surround - Sound played through many speakers in key places to give the the effect that sound is coming from certain places to give the effect of a deeper sense of immersion to the listener

Exorcise 2

How Can The Following Information Limit The Recording Of Sound?

DSP-Digital Signal Processor: a digital signal processor is used to filter and/or compress analogue sound as it measures it. As the analogue signals are converted into digital the sound files often become compressed in this process before they are converted back to analogue. it is this compression that causes the limit in quality of sound.

RAM-Random Access Memory: RAM is a way of saying something's memory or storage. The more storage available the larger the file size that is usable, leading to greater quality. But if one did not have a decent amount of RAM it limits the size of the file usable meaning that compressed file types may need to be used leading to a lack of audio quality.

File Format: depending on your file format, it can hold so much information. This information is what leads to the general quality of the sound. With file types that compress the information, such as MP3 files, the quality is far inferior to those which don't compress the information.

Audio Output: depending on your audio output, it can be used to give the feeling of  sound coming from certain places that when synced up with the audio being played can give a far deeper sense of immersion. Mono is the term used when sound only comes out one way from a source, stereo is used by two sources (left and right) and is used to make a person believe that the sound is coming from one direction or another, surround sound is used by placing many sources around the listener and playing certain sounds from the individual sources giving a far greater effect than that which stereo attempts to accomplish

Audio recording system.

In what types of scenario may you use the following audio recording equipment?

multi-track recording - you would use multi-track recording for when you are use 4 or more music tracks at the same time and want to make the music sound better so you would have 4 or more different parts 1 being guitar 2 being drummer 3 being singer 4 being bass and you want to make them all fit together and make it sound a lot better.

Analogue - you would use analogue when you are using your voice to record you maybe singing or maybe you're just talking to someone either way your using analogue there to begin with you would be singing into a microphone so that it could go onto a computer.

Software sequencer - you would use a sound sequencer if your on your computer because it is a computer software and it lets you create sounds using your keyboard from different musical instruments so that you can create music from home without using a instrument.

DAT - the only time you will be using a .DAT file is when your are saving it into Data on your computer or on your hard drive so that it will be turned into data and that it will be easier to use and see.