Happy New Year!
How was your Christmas and New Year Celebrations? Hope it was festive. Now on with this weeks topic, sound design and mixing.
As I said in my previous article on capturing sound, sound is as, if not more important than the visuals. Sound has to go through the same amount of cleaning and editing as the video.
Before I carry on with this article, it is worth pointing out, I only know information about the sound tools that I am using, and how they effect my audio files. I do not know the physical science behind sound, I am not a scientist. Now that I’ve got that out of the way, let’s begin.
Introduction To Sound Effects
In your sound editing software you should have a library of effects you can use to correct and create your sound. There are so many it would take me a lifetime to go through all of them and what they achieve. In this article I will start with the basics. Leveling, Noise Reduction, Parametric Equalization, Multi-band Compressor, Hard Limiter, Dynamics Processing and Reverb.
The first stage in creating your master sound mix is to level everything contained within the sound file. For example if you have two voices in one clip and one voice is louder than the other, it’s important that both voices peak at the same level. If you read my previous article on sound recording, I mentioned the sound meter starting at -48dbs increasing to 0dbs. Your sound editing software should have the same meter and a waveform reader. Your sound should be kept between -24dbs and -6dbs. Pick a level between these numbers and keep your voices peaking at this level.
No matter what microphone you use, it’s inevitable to pick up other noises. The first to look at removing is background hiss. In every sound recording there is a certain amount of background hiss. This process is simple, first highlight the only segment of your clip containing the hiss and tell your software to analyse it. Then highlight the whole clip and tell your software to reduce the background hiss. However there are some limitations. If the background hiss is quite loud, your audio will sound like it’s coming out of baked bean tin when reduced. There are settings you can adjust to get the perfect hiss reduction, but this is why it’s so important to get the capturing of sound spot on.
Now that the hiss has been reduced from your sound clip, you will notice certain clicks, pops and unwanted sound. For this it’s best to use a histogram reader whilst listening to your sound clip to become aware of them. Using the tools in your sound editing software you can reduce the unwanted noises in your histogram.
Simply put, the parametric equaliser tool in your sound editor is there so you can balance the frequencies in your sound file. When highlighted the graph presented to you should read on the Y axis the frequencies from 0hz to 48,000hz, and on the X axis how loud the frequency is in decibels. The line on the graph allows you to adjust the volume on each set of frequencies. As a baseline standard for vocals I like to use the preset “Vocal Enhancer”, and then click the LP on the right side of the toolbar to lower any high frequencies. This setup should be a good step in getting a nice crisp sounding vocal.
This is a different form of making sure your sound frequencies are perfectly levelled and do not peak above a certain decibel. In the Multi-band Compressor tool is the preset “Broadcast”. Once you select this you will notice a considerable jump in volume. Use the master decibel notch to take it down by three decibels. This setup will raise the desired frequencies to give you a nice crisp
sound without peaking too loud.
Hard Limiter & Dynamics Processing
These two tools are a variation on the same job. These two tools again make sure that your sound file doesn’t peak too loud. The hard limiter is more of a harsh tool for making sure your sound doesn’t peak above a selected decibel. I prefer to set mine to 6db. With the Dynamics Processing tool, it uses a graph to create a more dynamic cut off point for loud peaking sounds. Your original sound decibels appear on the X axis of the graph, ranging from 100 to 0. On the Y axis is the final decibel output of your sound. By adjusting the line on the graph you have control over the output of your decibels. On my graph, I create my first point at X-20 and Y-20, and a second point at X-0 and Y-0. I take my second point and drop it to Y-10 on the graph.
Reverb is the adjustment of yours sound’s reverberation. Noises sound different depending on the location and how the sound waves react to it’s surroundings. Reverb is an effect that allows you to adjust the way your sound reacts to it’s location, or create a location for your sound. For example you can use this tool to make something sound as though it’s coming from a grand hall, a small bathroom or a cave. Check out it’s presets and see what happens.
In summary you should now be able to create a sound mix for your vocal soundtrack and other sound recordings in your editor by:
- Leveling your sound file using the decibel and waveform reader.
- Reduce hiss, clicks, pops and other unwanted sound using Noise Reduction.
- Equalize your sound frequencies using the Parametric Equalizer.
- Level your sound frequencies using the Multi-band Compressor.
- Create a harsh cut off point for your loud peaking sounds using Hard Limiter.
- Create a dynamic cut off point for your loud peaking sounds using Dynamics Processing.
- Create an environment for your sound using Reverb.