Understanding Sound
Course Description
Sound is different from most of the other things we deal with in broadcast and media. It is about vibrations in the world around us and for the large part we cannot see it. In this module we look at how we define, quantify and measure sound and how the measurements we make relate to us in real life. The module looks at pitch and frequency, amplitude and loudness, quality and how it can be analysed down into collections of individual elements. Following on from this, it also looks at how sound behaves in the world around us and how the rules that explain how waves behave can be applied to explain the world of acoustics.
Who Should Attend
This session provides key underpinning knowledge which will help anyone who deals with sound on a day to day basis. It should be essential learning for all operators and technical staff and could also be of benefit to most in production. The module starts from first principles and therefore assumes no prior knowledge.
Course Duration: 3 hours.
Course Outcomes
At the end of the course you will understand:
- how frequency and pitch are related and that the relationship is a non-linear one.
- the enormous range of amplitudes the ear can hear and how this too is linked to signals we measure in a non-linear way.
- what a dB is, how to use it and why it is useful to us in measuring very wide amplitude signals.
- the significance of loudness in audio safety and noise regulation.
- what harmonics are and how sound waves are constructed from them.
- how reflection and diffraction are important concepts in the design of acoustic spaces be it a concert hall, studio or living room.
Module Cost - £80
Introduction to Audio
In this session, we will look at how sound is turned into analogue, then digital audio signals and back again before we can listen to it. We will examine how this process occurs, is quantified and the potential limitations. On the analogue side we will examine the requirement for balanced cables and how analogue has now been reduced to little more than just microphones and loudspeakers. We look at the standards for digital audio and why this is now so prevalent in everything we do. We discuss the idea of Nyquist frequencies and sampling rates as well as the requirement for high bit rates and the implications of systems which work at lower specifications.
The session then looks at how we quantify audio and the use of test tones and metering devices. From the old VU to the modern loudness meter, we examine accuracy and the scales they use.
Moving on, we will look at stereo sound. This will include a variety of topics including how stereo relies on both phase and level, as well as looking at different ways in which it can be encoded. How measuring phase is important to stereo and in providing good mono compatibility.
Who Should Attend
This session provides key underpinning knowledge which will help anyone who deals with audio on a day to day basis. It should be essential learning for all operators and technical staff and could also be of benefit to many in production. Because audio is fundamentally about sound, we recommend that those attending have a good working knowledge of sound, so they should either attend the Understanding Sound module first, or demonstrate a similar level of knowledge.
Course Duration: 3 hours.
Course Outcomes
At the end of the course you will:
- understand the different dB scales used to measure audio signals and their relationship to one another.
- recognise different test signals and know how they are used.
- appreciate the differences between VU, PPM and digital peak metering.
- understand the importance of loudness measurement in public perception of audio.
- be able to recognise the different digital audio standards and where/why they are used.
- understand the basic concepts of stereo and importance of phase in both the creation of stereo and in providing mono compatibility.
- appreciate the difference between AB and MS stereo.
- recognise an MS stereo signal and understand why we might want to use it.
Module Cost - £80
Mixers, Mics and Loudspeakers
Following on from the sound and audio modules, this module provides an overview of the equipment we use for gathering and processing sound. The session starts by examining how loudspeaker and microphones work and are defined. It moves on to look at the way in which microphones are connected to a desk before looking at the facilities which a sound desk provides and how they are used.
Who Should Attend
This session provides key underpinning knowledge which will help anyone who deals with audio on a day to day basis. It should be essential learning for all operators and technical staff and could also be of benefit to many in production. Because audio is fundamentally about sound, we recommend that those attending should have either attended the Understanding Sound and Introduction to Audio modules first, or demonstrate a similar level of knowledge.
Course Duration: 3 hours.
Course Outcomes
At the end of the course you will:
- understand some of the basic design parameters and limitations of loudspeakers.
- be able to choose a microphone which is suitable for your needs according to its polar pattern.
- know how different microphones can be used to record stereo.
- understand the concept of balanced lines.
- understand the basic block schematic for an audio mixer, including how faders are calibrated and used, how routing is used and how Auxilliary mixes are created and used.
- know what EQ is and does, and the different types of filter you might see.
- know the tools which make up the dynamics family and in particular compressor limiters. What they do and how they are used.
Module Cost - £80
Multichannel Audio
In this module we examine how multichannel audio is used in video. It will look at how it can be created, and how and when it is likely to be used. It moves on to examine how we store, transport and deliver multichannel audio and in particular Dolby D and E. The session goes on to look at the importance of metadata in defining this. It ends by looking at the future of multi-channel and object oriented audio such as Dolby Atmos.
Who Should Attend
This session is an introduction to multichannel audio for those who will be working with it and need to understand it better. It is however, an intermediate level module and requires a good knowledge of audio before attending, including all the content outlined in the previous three audio modules..
Course Duration: 3 hours.
Course Outcomes
At the end of the course you will:
- have discussed microphones and techniques for gathering surround audio.
- understand what an LFE channel is and why it is not carrying sound content.
- appreciate the importance of metadata in defining a set of sound channels.
- know the difference between Dolby D and E and the alternatives which might be used instead.
- discuss how multichannel audio mixes can be developed from many mono or stereo sources to create multichannel mixes in post.
- appreciate the importance of object based audio in delivering flexible balance, language, dynamics or other user requirements.
Module Cost - £80
Audio Compression
In a world of digital radio, TV, streaming services and file based audio content, almost everything we hear will be compressed to one degree or another. In this module we start by looking at the data rates for uncompressed audio before examining how audio can be placed in a file and what the common audio codecs do to the audio and the need for compression.
We then move on to examine the ways in which data can be reduced, looking at various techniques, both lossy and lossless, before spending some time listening to the results of audio compression and learning to identify the artefacts caused by lossy codecs.
Who Should Attend
This session is for those that want to better understand the implications of using audio codecs. It assumes a good understanding of sound and audio and we would therefore recommend that those wishing to attend this module complete the Understanding Sound and Introduction to Audio modules before attempting this one.
Course Duration: 3 hours.
Course Outcomes
At the end of the course you will:
- understand the difference between a wrapper/container and a codec with respect to files and streams.
- know the data rates required for the delivery of different audio standards.
- understand the difference between lossy and lossless compression.
- appreciate how different compression techniques work and what they can deliver.
- have discussed many of the common codecs used in media production and delivery.
Module Cost - £80
Sound 'Lite'
(N.B. This course also appears in the A/V Archive Modules Section)
Course Description
This is a shortened version of our standard sound modules which reflects the fact that some people need to know about sound, but perhaps will not be first and foremost audio engineers. It covers the basic concepts of how sound works and from that, how we measure and control sound. It looks at audio signals, the formats, qualities and limitations along with metering and monitoring systems and a brief look at the issues associated with multichannel audio and stereo. Finally it surveys the more basic tools which technicians can use to enhance or improve audio quality.
Who Should Attend
This session provides key underpinning knowledge which will help anyone working with AV content to understand what they are dealing with and identify and correctly deal with content. There are no prerequisites for attending as it explains everything from beginner level.
Course Duration: 3 hours.
Course Outcomes
At the end of the course you will understand:
- the concepts of pitch, loudness and quality and how they relate to frequency, amplitude and waveform envelopes.
- be able to read and understand different audio meters and standards.
- know how to identify and line-up audio test tones.
- understand the additional issues related to handling multichannel audio.
- know the basic tools which can be used to enhance or improve audio quality
