What is Audio?
When developing content for online learning, one of the crucial elements is having great audio. You can make a great video, but if the audio is poor, it can greatly detract from the learning experience. People have a greater tolerance for poor video than they do poor audio. In this section, you’ll learn about what audio is and how to create great audio to capture learner attention.
For our purposes, when discussing audio, it is usually in reference to the capture of sound. Audio is a term used in relation with computing and electronic devices for recording, processing, storing, and playing sound.
What we mean by sound, is that it is the audible portion of frequencies within the range of human hearing. There are also inaudible sounds that can be heard by animals or used in other applications for technology and medicine. To go a bit deeper, sound is a form of mechanical energy that travels through the air and substances and measured in hertz (Hz). Humans typically can only hear between 20 to 20,000 Hz.
Examples of Audio:
Next, we’ll provide some examples of poor and great audio.
Audio free from background noise:
- Audio that contains a lot of background noise makes it harder for students to concentrate on you and what you are saying. Subconsciously, the brain is trying to decipher all of the sounds and put them into context. This can quickly create fatigue and students will find it difficult to learn. Background noises include loud fans, A/C units, wind, other voices, and environmental noise.To understand what background noise is, try listening to the example of noisy audio below.
Now, listen to this example of clean audio, with no background noise. Can you hear the difference?
Audio free from distractions:
- If there are distracting noises in your audio it can immediately disrupt the learning experience. These include things like dogs barking, keyboard and mouse clicking, banging, ringing, etc.Here is an example of audio with distracting noises. Do you find it disruptive to learning?
Audio that is loud, but not too loud:
- When recording audio it is important to record at the proper volume to ensure students can hear you. It is also important the audio is not too loud to prevent distortion. Distortion refers to anything unexpected in the behaviour of a sound wave. This could mean you hear electonic interference, buzzing, or it just doesn’t sound correct, and therefore it is distorted in some way.When using the recording software, check that the recording volume levels are between -10dB to -6dB. It is also advised to keep your mouth 6 -12 inches away from the mic to prevent loud distortions in your recordings.Here is an example of voiceover audio in which a person recorded too closely to the mic, without checking the volume levels first. Can you hear the audio distortions?
Audio that captures the students attention:
- Once you have mastered some technical aspects of recording great audio, it is is equally important that you speak in an engaging way. Try to use inflection in your voice, and speak naturally with a quick, conversational pace (about 120-150 words per minute). You should communicate your passion for the subject matter using your voice. This, will keep learners engaged.
Audio that avoids errors:
- When you record your audio, it is important that you speak clearly and deliberately. You want learners to understand what you are talking about, and this will enable automatic captioning services to better distinguish what is being said.If you make a mistake – pause and start again. You can easily edit mistakes out using software to make it sound completely seamless.