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Audio Basics for Online Course Design

DavidAnderson's avatar
11 years ago

A great way to create an engaging learning experience for your audience is to include audio narration with your explanatory text and visuals. You could narrate the entire course, use audio just for character scenarios, or include first-person accounts from learners or Subject Matter Experts (SMEs)

And now it’s easier than ever to add audio to your online courses. High-quality microphones and recording software are readily available to everyone. In fact, both Windows and Mac computers ship with studio-quality recording apps preloaded. And if you don’t want to record audio in a third-party software suite, many content creation apps include their own audio recording tools. 

But even with easy access to high-quality microphones and recording apps, it can be tricky to make professional-quality audio if you’ve never done it before. Don’t worry, though; we’ve got you covered! By following these tips and tricks, you’ll be creating audio like the pros in no time.

Write a Narration Script

The first step to recording high-quality audio has nothing to do with audio equipment or software at all. Good narration starts with a script. 

To create a narration script, move the note text out of your course file, or wherever you’ve been compiling it, and into a table-formatted document. This way you can quickly see and read the text that needs to be recorded as well as make any changes on the fly (without losing your place). 

A narration script can take many forms, as long as it has these three main components:

  • Slide number: Slide numbers let you know which text goes with which slide. It’s also helpful for naming your audio files after recording.
  • Narration script: This is the actual text you’re recording. 
  • Narration notes: These notes provide direction for the narrator on how to read the script, including pronunciation guides, tips for emphasis, and narration pacing.

Here’s an example of what that might look like:

Slide #

Script

Notes

Slide 1

Sooner or later, everyone gets a flat tire. And chances are it won’t happen at a good time. I can hear some of you saying, “Why should I learn to change my tire? I have roadside assistance.”

Use a firm but friendly tone here. Pitch your voice a bit for the quote but avoid making it sound whiny. 

 

For more tips on writing effective audio narration scripts, check out this article: More Than a Dozen Tips for Writing Awesome Audio Narration Scripts.

Choose the Right Microphone

Now that you have your narration script, it’s time to take a look at your microphone. Whenever possible, you want to avoid using the microphone that’s built into your computer. Not only is it not made for capturing audio narration, but it can pick up mechanical noise from your computer. The same goes for microphones embedded in your earphones. They’re fine for phone calls and meetings, but shouldn't be relied on for professional recordings. 

For crisp, clear narration, invest in an external microphone. You don’t have to buy the most expensive one on the shelf, but with audio equipment, you really do get what you pay for. If you’re recording audio on a regular basis and want high-quality results, be prepared to invest at least $100.

There are many different types of microphones out there, but the two most common are omnidirectional and unidirectional. Each has its strengths and weaknesses. Deciding which one is right for you depends on what you’re looking to record. 

Omnidirectional

Unidirectional

An omnidirectional microphone picks up sound from all directions. 


It’s great for capturing:

  • Ambient sounds 
  • Outdoor sounds
  • On-the-scene sounds
  • People speaking in a large room 

It works best for situations where you don’t have a specific or target audio source or when you need to capture a scene or an environment’s audio profile.

A unidirectional microphone records audio sounds only from one direction (typically, the front), so it's usually the best type to use for audio narration. 


These do a better job of minimizing ambient or background sounds that might distract from the actual spoken words. 


The best ones come with enhanced pick-up algorithms that focus specifically on the narrator’s voice. 

 

Keeping all this in mind, many popular USB microphones can do double duty as omnidirectional and unidirectional microphones. Some let you control the mode manually with software, while others will automatically shift between modes if they detect multiple speakers. 

Consider Buying a Windscreen or a Pop Filter

With omnidirectional and unidirectional microphones, you have two main options to sharpen the quality of sound you capture. Let’s take a quick look at these helpful accessories.

Windscreens

Pop Filters

Windscreens filter the most sound and can reduce background ambient noise. You can generally find a windscreen for $20 or less.

Pop filters reduce popping sounds on “p” and “b” sounds by adding a layer of protection to the microphone. 

They also minimize unwanted breath sounds that happen when you exhale too close to the microphone. 

Most pop filters cost less than $20, though you can easily make your own. Just wrap nylon stockings around a clothes hanger and place it in front of the microphone before you start recording.

 

Again, if you're using a software-enhanced microphone, there may be virtual options for improving your sound and reducing unwanted noise. Check the settings before you begin recording and play with the different options to make sure they deliver the kind of audio output you’re looking for. 

Reduce Ambient Noise

While a good microphone and clever software can make your audio sound great, the direct audio input is only half the story. The other part of the equation is ambient noise. 

Build a Portable Studio Box

When you’re recording in a professional studio, the walls, floors, and overall room acoustics are specially insulated to cancel unwanted ambient noises. Since this type of setup is neither affordable nor portable for the average e-learning designer, many users build their own recording studio boxes.

With something as simple as foam seat cushions, you can put together a portable recording box that encases your microphone. It cancels out a large portion of ambient noise and gives you a quick bump in audio quality. Don’t have seat cushions or you’re stuck recording narration away from home? Use pillows!

For more information about portable studio boxes, check out this article: Record Better Audio with an Affordable Do-It-Yourself Sound Booth.

Silence Your Recording Space

It’s not possible to remove all sounds, but there are some things you can do to minimize ambient sounds. When possible, designate a particular room as your recording room and use it for your entire recording project. Your room’s layout, wall treatment, and furniture all affect the quality of your recordings. A carpeted room with furniture sounds different from an empty room with wood flooring.  

Here are some common ambient noises and tips for minimizing them:

  • Air conditioning: While it might not be ideal if it’s summer, you should still consider turning it off. Air conditioning is responsible for most of the noise in your office.
  • Computer: Computer fans and hard drives produce a lot of noise, so place your computer under your desk. The more distance you can put between your computer and your microphone, the quieter the room will be.
  • External devices: Disconnect unused computers, printers, and external hard drives. You’d be surprised at how much ambient noise idle electronics produce. The fewer devices you have running the better.
  • Hard surfaces: Even if you don’t have sound-dampening material on the walls like in a professional studio, you can make a big dent in ambient noise with carpet, window treatments, furniture, and any other materials that absorb sound. If you can’t make a portable studio box as described above, placing pillows around your laptop and microphone makes a huge impact. In fact, that’s what NPR correspondents do when they have to file reports from their hotel rooms!

Create a Consistent Environment

Even if you don’t have access to a professional recording studio, you can improve the quality of your narration by creating a consistent recording environment. Here are some tips that’ll help you do just that: 

  • Microphones: Use the same microphone each time you record. Microphones have personalities, and even if you always use a high-quality mic, you’ll notice a difference in the audio when listened to back-to-back if you don’t use the same one.

  • Capture your recording settings: Whether you’re sharing a recording setup with co-workers or going solo, you should always capture the important settings you use for your recordings for consistency. This includes input levels, microphone settings, and any other audio settings you’ve tweaked during recording. Take a screenshot or a picture of your settings before you close out of your project.
  • Microphone stands: Microphone stands come in both desktop and floor models. They help capture clean and consistent audio recordings by normalizing the distance between you and your microphone. Find the ideal distance by placing the mic stand in different positions, then note that in your recording settings.

Record Your Audio

Your room is set up and you’re ready to record, right? Almost! There are still a few things you should do before you jump into your first official take.

1. Check Your Mic Input Levels

This is one of the most important things you can do when recording. If the levels are too high, you’ll pick up cracks, pops, and other digital artifacts. If the levels are too low, it’ll be difficult to hear in the published course. 

A general rule of thumb is to keep your input levels between -12db and -6db. Since you’re recording digitally, you’ll find all audio recording programs make it easy to identify the ideal levels. Here’s what good input levels look like:

 

Notice how the levels are between -12 and -6? That leaves enough room for louder sounds without the risk of clipping.

Here’s an example of audio that’s too “hot” and likely producing unwanted distortion:

 

2. Test Your Recordings

After you’ve verified your input levels, record a short piece of test audio. Even with perfected settings, other recording issues can unexpectedly occur, such as a problem with hardware, an accidental audio setting change, or your voice not projecting as loudly as expected. It happens. Always take the time to record at least 30 seconds of test audio before you jump into your actual script recording.

3. Listen to Your Audio with Headphones

Headphones isolate ambient noise and help you hear your recorded audio clearly. Because they’re worn over the ears, you get the closest, most realistic playback of your audio. Also, most users will listen to your courses with headphones—especially those in corporate or academic settings—so you’ll want to hear exactly what they hear.

4. Record in One Session

For optimal consistency in your recording, it’s best to record your script in a single session. Even when you control your recording environment, your voice can sound different from one session to another. When you record in a single session, you’ll have more control over small but noticeable recording variables that occur.

If you do have to rerecord some of your audio, record the full paragraph or slide rather than a single word or phrase. Differences in your voice are less obvious when you rerecord larger sections of audio.

Summary

Now that you have a basic understanding of audio recording for e-learning, you’re well-equipped to record your next project like a pro.

Looking to take the next step and do even more with audio? Check out these articles:

Want some hands-on audio experience? Jump into one of these e-learning challenges and share your audio examples:

And remember to follow us on Twitter and come back to E-Learning Heroes regularly for more helpful advice on everything related to e-learning. If you have any comments, please share them below.

Published 11 years ago
Version 1.0
  • CarmenToro's avatar
    CarmenToro
    Community Member
    Are people recording in their office setting? It is impossible to reduce the ambient noise, we cannot turn off heat or air. I try to get permission to record at home but this is not always allowed.
    • AnnGordon's avatar
      AnnGordon
      Community Member
      I have recorded in an office setting, however the instructional design department in that company had set aside a room for people doing voice-overs. It wasn't insulated but at least there were no phones, no air conditioners, no background noises or voices, so it worked pretty well. All the little room had it in was a computer and microphone and office chair. Ann
  • DanEpstein's avatar
    DanEpstein
    Community Member
    On mic selection, omni vs uni is not the only consideration. You also need to decide between dynamic and condenser mics. The former doesn't require power, the latter does. Condenser mics will typically have hotter outputs than dynamics.

    You should also test out mics if you can so you can match the mic to the qualities of your voice. I switched from a mic that picked up too much of my low end to one that responds better to my mids and mid-his.

    Pay attention also to mic technique. Talking straight into a mic on axis increases the possibility of plosives. Try talking across the mic slightly off-axis to mitigate plosives. Pop filters alone won't necessarily do the job by themselves.

    When it comes to metering, the new standard is LUFS (loudness unit full scale). This method is better at accurately representing the loudness of sounds as actually heard by our ears. Most modern DAWs come with LUFS meters but you can also get one as a plug-in. Settling on a certain LUFS level (like -18 or -16) will help ensure your recordings are consistent.

    For those of you recording in less than optimum spaces, try a plug-in called Deverb. It does a pretty good job of removing the echo of untreated rooms.
  • AnnGordon's avatar
    AnnGordon
    Community Member
    What a great article. I especially appreciate the tip about getting a pop filter. I'll do that! Thank you for sharing your great information about recording.
  • Great article! I'm a musician and an audio engineer in my very little spare time so I tend to go overboard sometimes. (I use a condenser microphone into a mixing board so that I can EQ and apply effects to the mix before I go out to my recording tool.) One thing that I might add to this discussion is that you may want to record your audio to a little more high powered tool. Audacity is a great little freeware audio tool that can give you a ton of editing options that you just won't find in your audio tools packaged in eLearning programs.

    That said, Storyline has one of the better voice over/audio tools that I've found. Results on playback sound quite similar to the audio that comes out of the mixer for me. Others I've used I'm quite shocked at the drop in audio quality from the mix to the eLearning development tool.
  • CarmenToro's avatar
    CarmenToro
    Community Member
    Also do you recommend recording within Presenter or recording using other software and then importing the audio files.
  • yes its amazing the way you explained your thoughts about filters its great I am also working on the similar kind of projects and services and this is looking like the same.