It is always a good measure to process vocals before incorporating them into instrumentals. This process is meant to add quality to your vocals making them sound better in the final mix. These edits include normalizing the track to remove the fluctuation in levels within the file, and noise reduction to remove background noise that might result from recording in a noisy environment. Artists nowadays record on the fly hence a session might take place in a hotel room. You can also be a budding producer hence you might be recording in a not-so-perfectly soundproofed room. Lastly, you can add additional effects like reverb to add richness to the vocals.
Audacity has been my go-to choice when it comes to simple edits on recorded vocals and podcasting. For someone doing music production or composing you might encounter limitations as it does not have extensive features. This article however gives you an outline of some changes you will make to your vocals and how to mix the end result into a single file.
Import the files that you will use in mixing down. In this article, we will look at mixing vocals with an instrumental. You should have two or more audio waveforms.
The first step is to check how the audio play in sync. With this, you will be trying to ascertain whether the two files are if not in sync close to being in sync. With that said it would be hard for you to get two random files that you intend to mix together and have the combination work out. The two audio files can only work out if you know the information of the tempos of the said files and if these tempos are equal or close enough to each other. This issue will be a problem largely when you are working with downloaded files and looking to create music.
On the other hand, if you recorded one based on the other, for instance, you had the instrumental playing when recording your vocals then you don’t need to worry about synching. Also whenever you are mixing a podcast you don’t have to worry about the tempos being in sync.
The next thing that you will check is the sound levels of these independent files. When playing is one file overpowering or louder than others? Are you getting a perfect balance between the different sounds? In addition to addressing this concern, you want to achieve a balance where whenever someone listens to the end product the vocals are perceived to be in the mix and not separate. With this said you have to ensure you do not over-amplify the level of vocals.
On the left side of your audio waveforms, there are panels. These panels have sliders and a couple of buttons. The sliders are two: the gain and the panning sliders.
The gain slider will be the important one in this exercise and it is the one on top. Click on play then adjust this slider as the vocal plays. While doing this simultaneously note the right amount of gain that you will adjust the vocals to make them more prominent. Additionally, you can readjust the instrumental sliders by lowering them. While listening back to how my audio sounds the amount of gain that I need to make my vocals louder and balanced with the instrumental is +2 dB. This isn’t the standard value as you can find a value of 3 dB working fine for you. After establishing the amount of gain required to adjust the vocals, adjust the gain slider back to 0.0 dB, double-click on the waveform to select it, and then click on the effects option in the menu tab. From the dropdown option list that comes up, click on the Amplify option.
This will open this pop-up box.
In the first entry key in the adjustment figure that you got. In my case, I will key in 2.
Click OK to apply these changes.
The next step is adjusting the varying frequency bands within your vocal audio signal by EQing it. Double-click on the vocals waveform to select it then click on the effects option in the menu tab followed by clicking on the Filter Curve EQ option.
A filter curve EQ pop-up box will appear.
Changes to your EQ are done by clicking on the green line, holding down the white dot that appears on it, and dragging. Here are my ideal settings. Note that they might work for you as well or they might not provide ideal results also whereby you will need to make further readjustments.
Here is the adjustment that I made to my vocals. Below are breakdowns of each section.
The changes made in the A section are meant to pass louder frequencies and attenuate lower frequencies. This is useful in acts like killing the rumble in the recording. The midsection has the midrange frequencies. The adjustment that I have done is to attenuate the signal to remove an unpleasant cloudy feel to my audio. It is important that the frequencies existing within this range be clear. Lastly, section C adjustments are meant to add treble in the high frequencies.
Click OK to apply these changes. This process might affect your gain level hence you might readjust that by going to the Amplify effect in the Effects in the menu tab.
The next process to undertake is compressing the vocals to narrow the difference between the loud parts and the soft parts. First double click on the audio waveform then click on the Effects option in the menu tab. From the dropdown list click on the Compressor option. You will get this pop-up box.
The first slider, the Threshold is used as a cap to limit sounds that exceed a certain level. Mine is set as -20 dB. The Noise Floor slider is a cap to remove noises within the vocal recording. Therefore any signal below the set cap will be removed. I am using a -55 dB cap. The ratio is the amount of compression applied every time the audio goes beyond the threshold limit. A ratio of 2:1 will work great. You can also use 2.5:1 or 3:1. Lastly the Attack Time and Release Time are used to set how fast the compressor is applied once it goes over the threshold set. This is key in ensuring there are no fast and noticeable changes whenever there is a fluctuation in sound levels. A second is an ideal setting for these two. This breakdown is a quick overview of the compressor settings. Here is a complete guide for the best vocal compressor settings for Audacity.
Click OK to apply these compression settings.
If you are a podcaster using this process on one of your episodes you might need to Auto Duck the instrumental. This effect reduces the volume of one waveform giving prominence to another that you need to be louder and clearly audible. Since it’s a podcast and you want the vocals to be heard and not seem like they are competing with the instrumental Auto Ducking will come in very handy. This effect requires that the track that you want to keep the levels constant be placed under the one that will have the fade-ins and outs. Therefore if you have your vocals on the upper track like mine in the image above move them down.
Left click on the left side of the waveform where you have your track details, hold down the mouse and the pointer will change to a hand cursor. Drag it and place it on top.
Double-click on the instrumental followed by clicking on the Effects option in the menu tab. From the dropdown list click on Auto Duck. This pop-up box will appear with a valley-like image.
Adjust the sides to be less steep to avoid quick fade in and fade out but rather a smooth transition. Also, ensure that you do not make it less steep as well as the audio will have longer fade transitions. You should have waveforms looking like this.
You don’t need to do this if you are trying to mix the session into a music file. For someone making music effects like reverb and autotuning can be a cherry on top of the previous exercise that you have undertaken.
To mixdown everything into a single track, select all waveforms using Ctrl + A. Click on File in the menu tab followed by the Export option. From the dialogue box that pops up, key in how you want the file named, the format type, the file destination, and the formatting options for this file. (These formatting options are Constant for the Bit Rate Mode, 192 kbps for the Quality and lastly, pick Stereo as the Channel Mode unless you have a specific case requiring a mono file.)
Audacity is not designed with music producers as the primary target. From the article, you can undertake parts of the general music production process as you encounter limitations time and again.
However, the outlined process as mentioned in the article can be useful to podcast editors. Also, general audio producers who deal with audio like adverts that have a mix of vocals and instrumentals will find this process quite useful.