Four Audio Mixing Tips for Videographers
Once you’ve completed your edit, you’re ready for the “finishing” steps of color grading and audio mixing. We know a lot of filmmakers enjoy coloring their projects because that’s when you can breathe life into your footage—especially when you’re using a flat color profile. But one aspect of post-production we hear filmmakers struggle with is the audio mix. The questions we’ve received about recording, mixing, and sound design could fill multiple episodes—we’re planning to create more in-depth audio tutorials in the future—but for this episode, we wanted to focus on a few tips and tricks we think all filmmakers should know to quickly improve their audio.
We’ve outlined four quick, and easy things you can do to improve your audio mix. If you’re working with professional equipment, and have all your settings dialed in, these effects will give your audio a final polish. Anything can happen on a shoot day, so while these tools may not be able to provide major audio recovery, they can at least help work around some of the most common issues you may encounter.
One quick note, this article and Ask the Editor episode is focusing on tools found in Premiere Pro and the Adobe platform. If you’re working in FCPX, feel free to check out Ask The Editor Episode 3 where we go over similar effects that are found in Final Cut Pro X. Stay tuned for the accompanying blog post!
1. Audio Ducking Essential Sound Panel
Use Premiere’s automatic audio ducking tool to save yourself time
When working through a creative edit, we typically lay out our narrative elements first, in order to ensure that we can manipulate the music track how we need to flow with the overall story. If your workflow is similar, this tool found in the Essential Sound Panel, will save you a lot of time keyframing your music around your dialogue.
If you don’t have the Essential Sound Panel activated, you’ll want to add it to your Workspace. You can do this by navigating to “Window,” scroll down to where you see “Essential Sound Panel” and click on it to activate it.
Once you have it in your Workspace, go ahead and click on the panel to open it up. On your timeline, highlight all of your narrative elements that you want the music to dip down under, and click “Dialogue.” Once the Audio Type is set, leave that audio alone for now.
Next, highlight all of your music, and in the Essential Sound Panel click “Music.” Once the Audio Type is set the Effects panel should open up. Scroll down to the “Ducking” tab. If you only see the headings, click on the box to open up the controls. If the controls are all greyed out, click on the box on the right hand side of the control panel to activate the effect. From here you can start entering in the parameters you want the algorithm to use.
Make sure “Duck Against” is set for “Dialogue.” You can use this same technique for other types of audio elements as long as you assign them an Audio Type first.
If your narrative is pretty dense on your timeline, set the Sensitivity to high in order to pick up on some of the smaller gaps you have in your audio. I usually set this around “9” and then make any small adjustments that are needed.
“Reduce by” is going to be how low do you want the music to “duck” when the dialogue comes in, so this step involves a little bit of math.
For music or SFX/Natural Audio that comes in under A-Roll (Dialogue) we like to keep it between -18 and -21dB. I’ll let the music place and see where it is peaking and then determine how many decibels it needs to come down to fall into that preferred range.
For example, if the song is peaking at -6dB and I don’t want it to go higher than -18dB I would set this to Reduce By -12db.
I leave the fades on the auto-generated number. They don’t always hit exactly where I want them, but they get close enough that I can just adjust them as needed. When all of your parameters are set, hit “Generate Keyframes” at the bottom of the box, and let the algorithm do the work!
Everyone’s audio is recorded differently so these numbers may not work for you, but once you get it dialed in for your workflow, it should save you a great deal of time. When you’re working on longer edits that span several song transitions, this will be a life saver - I promise!
2. Noise Reduction in Adobe Audition
Remove background noise to improve dialogue clarity
Every shoot day will present its own unique set of problems, but this quick fix will help you improve any audio that is being affected by hum, hiss, water fountains, traffic, or airplanes. The audio we use in this part of the episode was recorded in a large space, with guests seated in front of the couple as well as surrounding them on a balcony above. The microphone is picking up a lot of shuffling from the guests that results in a noisy sound floor. Since the noise is consistent throughout the recording, we can easily remove this using Adobe Audition.
One of the great things about the Adobe platform is how programs are connected with the “dynamic link.” So once we’ve identified the audio clip we want to clean up, we right click on the clip, and select “Edit Clip in Adobe Audition.” Audition will automatically open with the clip ready to be worked on thanks to the dynamic link.
When you’re in Audition, zoom in on your clip and try to identify a couple seconds where just the noise you want to remove is present. We want a section free of dialogue so we don’t pull too much from the audio frequencies that are also registering in the voices. Once you’ve found a section of the audio clip that will work, click and drag over that section to highlight it. I would give it a listen a couple times to make sure you’re not accidentally picking up and audio from any of your dialogue.
If you want to loop the playback in order to fine tune it without moving your cursor back to the beginning each time, you can use the Loop Playback tool. At the bottom of the Program window, you’ll see an arrow that looks like it is turning in a circle. Click that in order to loop the audio set between your in and out points. You can also do this in Premiere, it’s located under the Program window as well. If you don’t see it, click on the “+” on the far right of the toolbar and then you can drag it onto the toolbar for easy access.
If the portion of the audio you have selected works, go to “Effects,” “Noise Reduction/Restoration,” and then “Capture Noise Print.”
This will take the “noise” in the highlighted portion and identify it throughout the audio clip. Make sure you click this part before moving forward, this is how the effect identifies what it needs to “fix.”
When the noise print has been generated, deselect the section of audio and navigate back to “Effects.” We’re going to use “Noise Reduction/Restoration” again, but this time click “Noise Reduction Process.” The effect panel will open, and from here you can fine tune how much of the noise you want to remove.
Noise Reduction is the amount of cleaning you want the software to do.
We typically pull it to 100% and then give it a few listens to see if it is pulling out anything from the speaker’s voice.
Reduce By is the number of decibels you want to remove from the areas that the noise is present in.
Again, we start off high (usually 20dB) and then adjust it after giving it a few listens.
Each type of noise is going to be present in different frequencies, so these parameters are not an end all be all. Play around with the settings and see what works best with your audio clip. You’ll be surprised to see how much more polished your finished edit sounds with clear recordings!
Once you have the settings dialed in to work with you audio the way you like, click “Apply.”
Double check the audio clip to make sure the noise you want to remove has been scrubbed and the speaker’s voice isn’t being degraded. When it sounds good, go ahead and Save.
Head back over to Premiere and after a couple of seconds the clip will “Render+Replace” with the new one from Audition on the timeline. Now the distracting noise should be gone and you can continue mixing your film.
3. Parametric Equalizer
Use Premiere’s EQ tool to balance the microphone’s emphasized frequencies and make your audio sound more natural
These next two effects are going to help balance and EQ your audio. If you’ve ever noticed your audio from a lav mic, shotgun mic, or recorder sounds a little harsh when you pull it into Premiere, this effect can help smooth things out to make it feel more natural.
If you’re working in an older version of Premiere Pro, this effect has replaced the EQ Filter. It will look similar to that effect, so if you’re familiar with EQ, you’ll be able to quickly navigate your way around this effect.
Within the Effects panel, search “Parametric Equalizer.”
You can save any effects to a “Favorites” Folder so you don’t have to look them up every time. Just right click in the Effects Panel and click “Create New Custom Bin,” rename the bin to your liking, and then drag all your preferred effects into the bin. Now you can just open that bin and pull the effects directly onto the clip.
Once you’ve added the effect to the audio you want to work on, navigate to the “Effects Controls” panel. Find the Parametric Equalizer, then click “Edit” to the right of “Custom Setup.” This will open up the Effect Window, where you’ll see a graph with several points on it.
The H and L are “shelves.” If you adjust either of those, you’ll start to cut off certain frequencies.
This will help pull out a low frequency hum, or hiss on the high end, just remember if you pull it too far you’ll start to mess with the frequencies in the speaker’s voice.
The points 1-5 represent different frequencies. If you pull those points up or down you’ll start to raise or lower those certain frequencies.
1 and 2 are the lows - raising these points will bring bass, or depth, to the speaker’s voice.
4 and 5 are the highs - raising these points will bring clarity to the speaker’s voice.
3 is the mids - slight adjustments here can make a big difference so be careful with the mids.
Below the graph you’ll see the frequency that is represented by each number, gain for each point, and then the Q/Width
If you adjust the Width you’ll adjust how sharp the curve at the point is. It can be wide and narrow or come to a sharp point. When you pull it all the way to a point you are “notching” that frequency.
Some recorders can pick up on a hum in around 50hz, so you can easily notch that hum out. Type “50” at the “1” point and adjust the Q to as narrow as possible. On the graph, pull the 1 point down to help remove the hum. Make sure to balance out the other points because this can start to degrade the speaker’s voice.
If the graph is a bit intimidating, there’s a “Vocal Enhancer” in the Preset dropdown. This will give you an idea of what a standard EQ looks like for dialogue. It can be a good jumping off point, but if you’re looking to achieve a particular effect like distortion, you’ll want to make further adjustments.
As you’re making these adjustments, you’re going to want to keep Gain in mind. As you pull up points on the graph, you’re boosting the frequencies. So if a piece of audio is already registering really high, you’ll make it louder by pulling frequencies up. If your audio does start to peak, you can use the “Master Gain” slider to the left of the graph in order to bring the overall gain down. On the other hand, you can also boost the gain from this slider if the audio is still registering too low after you EQ.
A very small adjustment you can make with Parametric Equalizer is applying a High Pass Filter. There is a High Pass filter in the Effects Panel, but applying it here will give you a little more control over what the effect is adjusting.
In the bottom left of the window you’ll see “HP.” Click on that to create a new point on the graph. Play your audio and look at where the speaker’s voice is registering. Pull the HP point to where the dialogue is peaking and you’ll notice the voice will become more clear and less hollow. This comes in handy if your audio has a slight echo, or tinny quality from the audio recorder.
On the reverse, you can also apply a Low Pass Filter, by clicking the “LP” button on the other side of the window. Again, there is a Low Pass Filter in the Effects panel, using it here just gives you a bit more control on how it is impacting the audio frequencies.
Once you have all the parameters set, you can copy+paste the effect to other audio clips from that source.
Whether you use preset settings or fine tune the audio yourself, balancing and equalizing your audio is going to make a huge difference in your final mix. If you have the settings on your audio equipment dialed in, and don’t run into any major environmental hurdles, this is a quick tool to sweeten your audio.
4. Multiband Compressor
Control the volume variability of audio sources to create a consistent and balanced level to your A-Roll
If the Parametric Equalizer is a little intimidating, or you’re looking for something that can also add Compression to your audio, then the Multiband Compressor will be your go-to tool. The nice thing about this effect is it combines two effects: Compression and EQ into one tool.
Navigate to the “Effects” panel, and search “Multiband Compressor.” Again, it might be beneficial to add your go-to effects to a “Favorites” bin. Either double click the effect or drag it onto the audio you want to adjust.
In the “Effects Control” panel, click “Edit” to the right of “Custom Setup” to open the effect window.
When the effect window opens, you’ll see four columns at the bottom. These are the “bands,” and each band represents a different group of frequencies, hence the “multiband” name. The low frequencies are on the left and the high frequencies on the right. Similar to the points 1-5 in Parametric Equalizer. Making adjustments to these four bands will allow you to EQ as well as apply compression to any or all of the bands.
Threshold: This tells the compressor when to turn on and when to turn back off.
If you set it at -6db, anytime your audio goes above -6 it will turn on and once the audio goes below -6db is will turn off. So set this to the point you want your audio to peak at. We typically like dialogue to hit between -3 and -6db, so we would set it around -6db.
Ratio: How much the compressor pulls the audio up or push it down to meet that threshold.
This one involves a bit of math: 2:1 is half as big, 4:1 is a quarter, etc. So, if we set our threshold to -6db and the audio goes above it, the Compressor will kick in to bring the audio back down to that -6db. The Ratio will be the amount the Compressor does to bring the audio back into range. 4:1 is usually a good ratio for Dialogue, so if the audio goes 8 decibels above the threshold of -6db, the effect will bring it back 4 decibels.
Attack and Release: How quickly the compressor turns on, and how quickly it turns off.
If your audio is going outside of the threshold, this is how quickly the effect is going to pull the audio back into the desirable range, as well as how quickly it will stop once the audio is back in the preferred range. If this is too fast or too slow, you’re going to get distortion in the speaker’s voice.
As you play a section of audio, you’ll notice different color wave forms. These colors correspond with the four columns or bands. This will help you EQ your audio because if you notice a slight hiss in your audio, you can adjust it by pulling the slider down on the high band (the one all the way to the right). Pulling the slider up or down will boost or lower the frequency. If you click the “S” at the top of each band, you can solo each section to better adjust each one individually. The low-mid (orange) is where the majority of your dialogue will be registering, so this one might take a bit more work.
At the top of the Effect Window, you’ll see a Presets dropdown - which is a great starting point. “Kill the Harshness” and “Hiss Reduction” can quickly remove a slight hum or hiss. If the noise you’re trying to remove is really noticeable you’re probably better off using Noise Reduction in Adobe Audition - which we went over at the beginning of this article.
These tools are great places to start for anyone that isn’t familiar with audio mixing, and if you’re already happy with your audio, will allow you to balance and sweeten it even further for a film. If anything, these tools will help speed up your editing and allow you to deliver a well balanced final film.
If audio just isn’t your passion, we’d be happy to help! Check out our Audio Only Services, and let our Audio Engineer balance, repair, and sweeten your film!