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My goal for this episode is to give you an introduction to using audio plug-ins in post-production to improve the quality of your audio files.
I’ll be honest; plug-ins used to scare me. They used to be confusing. I knew that you could use them to enhance your audio quality, but I had a ton of questions:
Which plug-ins do I need to learn? How many should I use on each track? Is there a right/wrong way to use them? Do I need to buy the plug-ins that the professional mixers use, or are the stock plug-ins good enough?
Those are just a few of the questions I’m going to answer in this episode. I’m also going to introduce you to the concepts of signal flow and gain staging, and talk about how you can make your audio sound good with the stock plug-ins that come with nearly every editing program.
Highlights, Takeaways & Quick Wins
- Here’s the most important thing to know if you want your audio to sound good; avoid clipping in all stages of your signal chain.
- Try sending your vocal tracks to a bus or aux track and using plug-ins on that bus track instead of the master track.
- You don’t need special third-party plug-ins to make your podcast sound good. The stock plug-ins are great and many professional mixers use them.
- Do a great job with recording clean audio at the right levels and you won’t need as many plug-ins.
- Don’t assume that you can make your track sound better by adding a ton of plug-ins. If it sounds good the way it is, leave it alone.
- 2:20 We all want to make recordings that sound great. I do, anyways. I hope you do too. The quality of your audio depends on many factors, including the microphone you use, the room you record in, the interface or audio device you use to create the recording, and the file type and bit rate that your mic or interface is capable of recording.
- 2:49 This is why I recommend buying a dynamic microphone and an interface that is capable of recording 24 bit audio (see my gear guide here). Most modern USB or Thunderbolt interfaces are capable of recording 24 bit audio.
- 3:03 Most of the USB microphones I’ve checked out record in 16 bit, which is ok, you just have to be a little more careful when setting your input gain levels to make sure that your audio levels aren’t too high or too low.
- 3:22 24 bit is better than 16 bit because it has more dynamic range; even if you record at lower levels, your signal will be cleaner when you add more gain to it later in post-production.
- 3:36 Bottom line; buy audio interfaces or USB microphones that are 24 bit. The noise floor will be lower in recordings made in 24 bit.
- 3:56 If you want to read a more in depth explanation about 16 bit versus 24 bit audio, here’s a link to a great article.
What is Signal Flow and Gain Staging?
- 4:23 I used to hear people talk about signal flow and gain staging, and I had no idea what they meant. I assumed it was some fancy scientific term that only real audio engineers understood. Some kind of magic thing that would make my audio files sound better.
- 4:45 The good news is that it’s actually not that complicated. Here is the super simplified version.
- 4:54 Signal Flow is the path that audio takes from beginning (when you talk into your mic) to the end (when you export your stereo or mono master track out as an MP3). The path normally looks like this: your voice, into the microphone, through a couple of plug-ins, to the master track, exported as an MP3.
- 5:36 Gain Staging is managing the levels of your audio as it passes through the different parts of the signal flow. You don’t ever want your signal level to hit 0db (which is the ceiling, this will cause clipping and digital distortion).
Here’s the most important thing to know if you want your audio to sound good; avoid clipping in all stages of your signal chain.
How Does Signal Flow Work?
- 6:47 Let’s say you open up Garageband. You create a track with your microphone selected as the input source. You hit record and talk for awhile. Now you’ve got an audio file in garageband. You can then use plug-ins to affect that audio before exporting it as an MP3 file.
- 7:20 In almost every editing program, the audio goes through the plug-ins on its track from top to bottom.
- 7:40 So you start with the raw recording. The audio from that recording goes through to first plugin on the track, then the next one, then through every subsequent plugin until there are no more plug-ins left. You can then adjust the gain (or volume) level of the audio with the fader or volume knob on that track before it gets sent to the master track. It then gets processed by any plug-ins on the master track before being sent out to your headphones or speakers.
What are Audio Plug-ins?
- 10:14 From Wikipedia: An audio plug-in, in computer software, is a mini-program or app that can add or enhance audio-related functionality in a computer program. Such functionality may include digital signal processing or sound synthesis. Audio plug-ins usually provide their own user interface, which often contains graphical user interface widgets that can be used to control and visualize the plug-in’s audio parameters.
- 11:05 That’s kind of techincal. Here’s my explanation for normal people.
- 11:18 Back in the day, recording studios used to have these big hardware boxes to affect the way audio recordings sounded. They would record the audio from a microphone onto tape, then from that tape machine out to a hardware unit that changed the way it sounded, then back into another tape.
- 12:04 There was an EQ box to change the balance of the frequencies. If you had too much bass, you’d turn a knob and reduce the bass. If you wanted more treble or high end brightness, you’d turn a knob.
- 12:19 If you wanted to reduce the volume of the louder parts of your recording and increase the volume of the quieter parts, you’d use a compressor.
- 12:28 Those are just a few examples of the hardware units that audio plug-ins have replaced. The good news is that you don’t have to buy and keep these big hardware units anymore to change and enhance the way your audio sounds. Programmers have emulated the effects that you could get from using these big boxes and turned them into mini programs that run inside of digital audio workstations like Garageband, Logic Pro, Ableton, Audition, and Pro Tools.
- 12:58 This is awesome! We now have access to software versions of hardware that used to cost tens of thousands of dollars. To compare, a copy of Logic is $200, Garageband is free or $15, you can lease a copy of Adobe Audition for $20/month, and all these programs come with dozens of free plug-ins. It’s truly amazing.
How Do I Add Plug-ins to My Tracks?
- 13:30 Modern editing programs come with some great free stock plug-ins. Here’s how to add plug-ins to tracks in Garageband and Logic.
- 13:43 In Garageband: Click on the track you want to add plug-ins to, then go up to the menu bar at the top of the screen and select view. You’ll see a dropdown menu, click on “Show smart controls”. You see controls pop up from the bottom of the screen. Click on the “i” bottom at the left of the control window (it’ll be right next to a button that says “Master”). If you look down a little bit, you’ll see an arrow next to some text that says plug-ins. Click the arrow, then you can click in an empty slot to add a plug-in to that track.
- 14:27 If you click on the master button in your smart controls window, you’ll see a space to add or change the plug-ins that are on the master track.
- 14:39 In Logic Pro X: Inside Logic, you can add plug-ins to any track (including the master track) by going up to the view menu and selecting “Show Mixer”. Or you can hit X on your keyboard (that’s how I do it).
- 14:51 From there, you’ll see vertical channel strips that correspond with each audio track that you have. There’s a space under “input” that has “Audio FX” next to it. That’s where you can click and add plug-ins to each track.
Should I Put Plugins on Individual Tracks, or Bus Tracks, or the Master Track?
- 15:10 Cory Miller asked: Is it better to add plug-ins to just single channels, or is it okay to send similar sounds to a buss channel and add the plug-ins there? I do usually put plug-ins on individual tracks, but I also send my vocal tracks to a bus track that has a few more plug-ins on it. In some DAWs (Logic included), you can select the output for each track. I like to send the output of every vocal track to a bus (or aux track) for additional processing (some people call this mastering).
- 16:29 So I send all the vocal tracks to a bus, and on that bus track I have some plug-ins (usually a compressor, a de-esser, and a limiter). If I put those plug-ins on the master track, then the music would go through them too, which would make the music sound a little funny. I don’t want that, so my solution was to put the plug-ins on the bus track instead.
Try sending your vocal tracks to a bus or aux track and using plug-ins on that bus track instead of the master track.
Which Plug-ins Do I Need to Learn?
- 17:27 There are 7-8 plug-ins that I use for almost every podcast; Gain, EQ, Compressor, Noise Gate, Expander, De-Esser, and Limiter. You’ll find a version of these plug-ins in most editing apps (with the exception of the Expander, which isn’t included in Garageband, as far as I know).
- 18:22 The gain plug-in allows me to adjust the gain (or volume) level of each track before it goes to the other plug-ins. So if I have a track that was recording with too much gain, I can turn it down a few DBs. If I have a track that isn’t quite loud enough, I can turn it up a few DBs. My goal is to get the loudest peaks of every track to around -12db before sending it through the plug-in chain.
- 19:34 The EQ (or equalizer) plug-in is how I add or reduce gain (volume) to bass, mid-range, and treble, and fix problems like harshness in the high-end, sharp “S” sounds, dull-sounding tracks, muddy sounding tracks, and other problems like that.
- 20:02 I did a screencast called Intro to EQ that you should check out if you’re interested in learning how to use the EQ plug-in in Logic or Garageband (the concepts will transfer to any editing program, though).
- 20:14 The compressor plug-in allows me to reduce the dynamic range of the track; it reduces the loudest parts of the track so I can turn the overall volume of the track up a little bit, this way the entire track is more even in volume. I did a screencast about compression that explains how to use the compressor plug-in in more detail.
4. Noise Gate
- 21:15 The noise gate plug-in has a volume threshold you can set so that anytime the volume of the track goes under that threshold, the plug-in will reduce the volume of the track to zero. I usually set the threshold around -32db, but it depends on the gain level of the track, so check out this great tutorial and get familiar with the various controls on a typical noise gate.
- 22:19 The expander works kind of like a noise gate; you set a threshold and it boosts the signal above that threshold. This plugin is subtle but can help reduce background noise. Here’s a screen shot of my default setting for the expander plugin, and here’s a screencast tutorial.
6. Noise Removal.
- 22:48 Q: Does Logic Pro have a noise removal plug-in similar to the one Audacity has?
- 23:03 Yes, it’s called Speech Enhancer. It’s a legacy plug-in, which means you’ll have to hold down option while clicking on an empty plug-in slot, then you can find it in the Legacy sub-menu in the popup window. It’s a great plug-in for removing background noise, but be care not to set the threshold too low, otherwise it can cut off some of the speech. -40 to -35db seems to work well for most tracks.
- 24:02 The de-esser works exactly like it sounds; it’s a compressor that removes the harsh “S” sounds from a track. You tell the plug-in which frequency range you want it to watch (usually around 5k), and it will compress that sound in that range when it crosses a certain volume threshold. It’s especially useful if your track has harsh S sounds that ocassionally pop out. Be careful not to be too agressive with this plug-in, though, as too much de-essing can make someone sound kind of un-natural, like they have a cold. Check out a screencast about the De-Esser plug-in in Logic here.
- 24:52 The Limiter is similiar to a compressor (and limiting often an option in compressor plug-ins), except that no audio will be allowed to go higher than the threshold you set. I usually put a limiter plug-in on the master track to make sure that the audio level of the master track never passes above -0.4 or -0.8db. The limiter plug-in makes sure that the MP3 file I bounce won’t have any clipping in it (assuming I’ve done a good job of gain staging).
Do I Need Third Party Plug-ins?
- 26:07 Q: Are the third party plug-ins better than the stock plug-ins? Do I need to expensive plug-ins like the pros use?
- 26:34 In most situations, the stock plug-ins that come with your editing software are fine. But there are some third-party plug-ins that solve very particular problems. It’s up to you to decide if you are willing to invest the money to get the plug-ins that will solve those problems.
Third Party Plug-ins that I Recommend:
- 27:10 I really love Izotope’s RX5 plug-ins – $300. RX5 is a stand-alone editing program for repairing all kinds of problems with audio, but it also comes with plug-ins that you can use in your DAW including:
- Dialogue Denoiser (for removing background noise)
- Declipper (for fixing clipping)
- De-reverb (for reducing room echo)
- 28:26 There’s a few plug-ins from Waves that I really like. I bought the Gold Bundle (Full price is $799, but it is often on sale for $200), which includes 35 plug-ins for mixing and mastering, my favorite of which are the De-Esser and the L1 Limiter.
- 29:09 Another bundle that I like is the CLA Classic Compressors ($599 full price, but occasionally goes on sale for less, I think I paid $79): The CLA-3A Compressor is my favorite right now. If you ever see that bundle go on sale, I can recommend picking it up.
You don’t need special third-party plug-ins to make your podcast sound good. The stock plug-ins are great and many professional mixers use them.
Can I Use Third-Party Plug-ins in Garageband?
- 30:24 You can use third-party plug-ins in Garageband, but you’ll need to change a setting in Garageband before they’ll work. Download and install the plug-ins you want to use, then go into settings in Garageband, click the audio/midi tab, and check the box that says Audio Units. Now your plug-ins should show and be available to use on your tracks.
What Order Should My Plug-ins be in?
- 31:16 Jason asked: Does the order of my plug-ins make a difference? If so, what order do suggest putting them in?
- 31:28 The order of your plug-ins does make a difference. This depends on what the track needs, but very often, I find myself putting plug-ins on tracks in this order:
- Gain adjustment
- Noise Removal
- 33:32 On the vocal bus or the master track, I’ll put these plug-ins in this order:
If you’re interested in learning more about plug-ins, I put together a list of the best resources for learning mixing and mastering in the show notes for episode 18.
- 34:59 Audio plug-ins can improve the quality of your audio and even fix some minor problems, but they can’t fix everything. You should try to get the best, cleanest recording possible.
- 35:11 Avoid clipping at all times. Try to keep your audio levels under -6db until they get to the master track, then add a light compressor and a limiter to the master track to add a few db of gain.
- 35:32 Don’t be afraid to experiment with plug-ins. They won’t alter or damage your audio tracks.
- 35:48 Trust your ears. If you add a plug-in or make a change to a setting and it sounds bad, try to figure out why.
- 35:57 Before you start adding plug-ins, figure out what’s wrong with the track. Identify the problems and use the appropriate plug-ins to fix them. Plug-ins are tools. If the track isn’t broken, you don’t need to fix it.
- 36:13 Stock plug-ins are perfectly fine and will work great for editing podcasts, but there are a few third-party plug-ins that you can buy to solve very specific problems like clipping and background noise. It’s up to you to decide if you want to invest the money to get those plug-ins.
- 36:29 Start by learning how to use the EQ and compressor plug-ins. You’ll find yourself using these two most often when working with vocal recordings.
- 42:44 Cory Miller said: Good points on starting with good audio. I’ve heard it’s helpful to think about recording/editing in a similar way to taking photographs and editing them. The more you can do in the camera with positioning, exposure, aperture, and all of that is better so you can do minimal editing and adjustment later on. That way you have as much of the naturalness as possible.
- 43:11 That’s a great analogy. It also ties in with a couple of other questions I got.
- 43:26 Q: Does every track or project need plug-ins?
- 43:45 Not every track needs plug-ins. To use Cory’s photo analogy, not every photo needs editing. Plug-ins are meant to enhance certain tonal qualities or fix problems. In podcasting, it’s more often about fixing a problem.
Do a great job with recording clean audio at the right levels and you won’t need as many plug-ins.
- 44:57 Q: Can plug-ins fix every problem? No. They can fix or improve a lot of problems, but if you go and record a track in your bathroom, or in a room with a ton of background noise, there won’t be a way to make that recording sound good. Focus on getting a clean recording, and then use plug-ins to make suble tweaks to improve the recording.
- 45:32 Jason asked: What is the best balance of plug-ins that won’t degrade the audio?
- 45:37 It depends on what the track needs. I play around with the order of my plug-ins, but I usally end up putting a noise removal plugin first, then an EQ, then a compresser. My recently, I’ve been focusing on doing as little as possible. I use to go a little crazy with the plug-ins, putting a bunch on a track to try to make it sound as good as possible. Now I just focus on solving problems.
Don’t assume that you can make your track sound better by adding a ton of plug-ins. If it sounds good the way it is, leave it alone.
- 50:54 Cory Miller asked: Should you only use plug-ins that your editor/mixer also has? I have quite a few third-party plug-ins for Logic, and if I wanted to send off my music to a mixer or producer that didn’t have those plug-ins, I’d be out of luck. What’s the best practice for using plug-ins when coordinating with other people?
- 51:24 Great question, but I don’t think this is going to be common for most people doing podcasts. I think if a podcaster has an editor, they’re going to record a raw audio file and send it to their editor for post-production.
- 51:43 If you are producing music and want to collaborate with another musican or send your project to someone for mastering, then apply the plug-ins to your track, then bounce that track in place. That’ll apply the effects to the track and give you a new audio file which you can then send off to someone else.
- 52:58 Q: I’ve heard you talking about a hardware processor you use (a DBX 286, I believe), do you use that inserted as a plug-in or do you run your signal through that on the way in?
- 53:14 The DBX 286 is a hardware unit that has a microphone preamp, a compressor, a de-esser, a high and low frequency enhancer (not quite an EQ, but similar), a noise gate, and a limiter. So the DBX 286 is like a plug-in chain that you’d have in your DAW, except the processing happens before the signal from your mic reaches your audio interface and goes into your recording software.
- 54:22 I used to use it, but I wasn’t happy with the sound I was getting out of it. I have the DBX 286a (most people get the 286s), so I don’t know if it sounds worse than the 286s, or if it was just user error. I need to spend some more time with it to see if I can get a better sound. Caleb Wojcik did a great video about how to configure the DBX 286s, so go check that out if you plan on using one.