Recording Your Voice with Advanced Techniques

Mixing and Mastering is the skillful process of enhancing the sound quality of your audio with EQ, compression, and gain so that it is consistent from track to track and so that you can offer it to the largest audience possible in a standard file format that’s accessible on nearly any device.

Mixing and Mastering Your Audio

A good rule of thumb when editing your audio tracks is decreasing rather than increasing frequencies wherever possible. Decreasing undesired sounds is always less obtrusive as increasing too much can make a track too loud and lead to digital distortion when encoding the file.

Compressors - Reduce the Dynamic Range

A compressor’s basic function is to reduce the dynamic range of an audio recording, which is the difference between the loudest and softest sounds in a recording.

By reducing the volume of the loudest sounds, a compressor lets you raise the level of the entire audio track, making it all sound louder than it actually is. Compression can be a big help in achieving intelligible audio tracks with a more uniform volume that will sound great on any stereo system.

A compressor consists of a level detector that measures the incoming signal, and an amplifier that controls the gain by the level detector.

A Threshold control sets the level at which compression begins. Below the Threshold, the compressor acts like a straight piece of wire. But when the input level reaches the Threshold, then the compressor begins reducing its output level by an amount determined by the Ratio control.

The Ratio control establishes the proportion of change between the input and output levels. If you set the compression Ratio to 2:1, then when the input signal gets twice as loud, the output signal will increase by only half.

If you set the Ratio to its maximum (10:1 or more), the compressor becomes a “limiter” that locks the maximum level at the Threshold.

While a compressor can level out a recording, high levels of compression can also introduce artifacts including “pumping,” in which there is an audible up and down change in volume of a track, or “breathing,” which sounds like someone breathing as the background noise level goes up and down.

Expanders Increase the Dynamic Range

An expander is the opposite of a compressor. As the level of the audio signal gets louder, the expander’s amplifier turns up further, making loud signals even louder. An expander can be used to reduce noise in a process called downward expansion. In this case, you set the Threshold just above the level of the background noise. The expander will then raise the volume of everything above the Threshold, but won’t change anything below the Threshold, thereby lowering the perceived background noise.

Normalization Evens Out The Loudness

Normalizing increases the gain of the audio file until its loudest point is at maximum level. The overall signal level is now higher, which makes for clearer audio, and also gives the encoder more bits of data to work with and reduces encoding distortion.

The only downside of normalizing is that it increases the noise as well as the audio signal so it should be used carefully. It should be your last step before encoding, and you may not need it at all.

Production Techniques

Mixing in your slate, imaging, and musical transitions

Now is the time to mix in your slate. Slating a demo simply means stating your name before you go into your read. State your name, pause, start your read. That’s it. Don’t tell them your life story or go into a sales pitch. Keep it simple.

As with all things, things change. You don't necessarily need to use slating in the case of online marketplaces because it is somewhat redundant. The client has everything they need directly in front of them. Given this fact and taking into account preferences of companies using the online marketplace, many talent are now choosing to simply read the copy without a slate. This goes for generic demos as well. The slate takes up time and can also take away from the read.

When in doubt, do what the client or person casting has asked you to do. If they require a slate, slate. If they specify that you simply read the copy, only read the copy.

If you do opt to include a slate, some voice talent have an announcer of the opposite gender or a child voice talent introduce them which have been met with marginal success for some but that is an exception, not a rule. The majority of clients find it to be a confusing distraction, particularly when it comes to auditions, so we recommend you do your own slate.

Once you’ve slated your demo try fading your background music in at the beginning of a new segment to separate between each spot on your demo. Lower the volume level of the music when you’re speaking so that listeners can hear every word you say. At the end of the segment, fade your background music out.

Use musical transitions between the various segments of your recording. These musical transitions are known as bumpers, stages or sweepers.

Converting Your File

Knowing how to convert audio from any format into an MP3 is an important skill to have, and since you're reading the Professional's guide, it's likely a skill you've already got!

Most demo hosting services on the web, including Voices.com, require demos to be in MP3 format. Because MP3s are heavily compressed, it is the best way to send files over the Internet both by FTP services and email as they are much smaller than WAV files and other digital file formats.

Due to the amount of compression on MP3s your previously perfect audio quality may sound scratchy, distant, or muffled after it’s been converted to MP3 format. A little remixing may be required. In most cases, simply boosting the gain will do the trick. The important thing to remember is to boost the gain only AFTER you’ve converted your file to MP3 first.

Whatever recording program you’re using, you should have the option to save or export your recording as an MP3. If the only option is to export as a WAV file, that’s okay too.
You’ll just have to complete an extra step to convert the WAV file to an MP3 file. An easy way to do so is with iTunes.

Here’s a quick tutorial:

  1. Open iTunes. If you don't already have iTunes, you can download iTunes here: http://www.apple.com/itunes/download/
  2. Import the audio file from your computer into iTunes by going to the File menu, then selecting 'Import.'
  3. You'll see the file you just imported in the Library. You can access the Library from the source menu on the left hand side of the iTunes window. Consider changing your file names to more relevant file names such as 'commercial voice-over demo,' 'narration voice-over demo' or 'character voice-over demo.' Type your name in the Artist field.
  4. Next, you'll be setting up the file format that you want to convert to. In this case, you will want to convert to MP3. Still in iTunes, select File, then Preferences.
  5. In the iTunes Preferences, select 'Importing' from the tabs at the top of this window.
  6. Under Importing, you'll see a pull-down menu that will allow you to choose what type of file format you would like to create. Select 'Import Using: MP3 Encoder.' Stay with the default setting of Good Quality (128 kbps).
  7. Once you see the file in iTunes, click it once to highlight the file in blue.
  8. From the Advanced menu at the top of the iTunes window, select 'Convert to MP3.'
  9. iTunes will create the converted MP3 file beneath the original audio file. The second file is your MP3.
  10. These files will be saved on your hard drive in your iTunes Music folder. You will also see the files displayed in your iTunes Library.

Checking Your Mix To Review Your Recording

See if your mixed down MP3 sounds good on a variety of stereo systems such as your computer speakers, headphones, portable stereo and car stereo. If your mix translates well from system to system, you know that you have created an excellent work of art.

Structure for Saving Audio Files

Organize your audio recordings. Save time by getting organized right from the start. Create a file folder in ‘My Documents’ called ‘My Voice-overs.’ In your ‘My Voice-overs’ folder create new folders for each client that you have, or will be working with. Having a defined structure for your client's audio will not only keep you organized but it will help you plan your work in advance. When saving your work, export your voice-over recording as an MP3 file.

Save the file as: ClientName_Project_Version_01.mp3

File Sizes

WAV or AIFF files are uncompressed pure audio in PC and MAC format. They are huge files with superior audio quality and are often what clients need their projects delivered in for the final product.  MP3 or AAC compressed audio makes it much easier to stay within any bandwidth limits and are what can be uploaded to Voices.com, sent via email, and generally shared online.

To encode audio you need to know the bitrates and sample rates. 128 kbps and 44.1 kHz (44,100 is standard MP3) are ideal.

A professional sample rate will be much higher kHz. The sample rate is a basic measure of how close the sound is to the original. The smoother and clearer the sound is, the higher the rate is.

Applying a Rule of Thumb

The most widely used digital audio format is the MP3.

Default setting

  • MP3 file, stereo, encoded at 128 kbps as a minimum, but can go up to 320 kbps
  • MP3 equation is: 1 minute of stereo digital audio, encoded at 128kbps = 1MB MP3 file

Recapping The Key Points About Mixing and Mastering

In this chapter, we discovered how easy it is to make your recording sound exactly the way you envisioned it. After mixing and mastering your voice-over, you will be rewarded with your very own demo-ready MP3 file. If some of these elements are overwhelming and not within your area of expertise, there are a number of resources you can find online that can help remotely, such as V.O.StudioTech or Edge Studio.