If you’re interested in my take on living in Australia when you’re not Australian, check out my old podcast, Lost Out Back. If you’re not, sit tight—I hope to have something a lot more relevant to this site for you to listen to soon!
They say the audio quality is far more important than the picture quality when it comes to producing watchable video for the Web. When all you’ve got is the audio, it’s even more important!
No matter what your podcast is about, a little extra work to get the details right will go a long way. Here are a few quick tips that I’ve learned through hard experience. If you have any to add, leave a comment and I’ll post the best ones in an upcoming Tech Times!
1. Get a Nice Mic
There are crappy microphones, and there are really crappy microphones. If it came with your computer, or if you found it hanging in a blister pack at your local discount computer shop, it’s probably not suitable for producing a nice-sounding podcast.
Good podcasting microphones are directional, which is to say they capture sound from directly in front of them, and not the various hums and echoes in the rest of the room. A really good microphone can make your voice sound more pleasing than it does in real life!
Microphones are one of those technical areas that you can sink a whole day into researching (dynamic vs. condenser, directional vs. omnidirectional, USB powered vs. phantom powered), and still not be sure what to buy at the end of it. If you’re just getting started, however, Macworld’s recent review of 8 good quality USB microphones is a great place to start.
For best results, think about getting a pop filter for your mic. They’re relatively cheap, and can squash those popping Ps that can ruin an otherwise perfect podcast.
2. Pick a Good Space
It goes without saying that a quiet space is essential, but the room you choose to record in can make a big difference. Blank walls, big windows, large tabletops, and hardwood floors all create echoes that can completely ruin that “up close and personal” sound you’re going for.
A good directional microphone will block out a lot of the echoes, but anything you can do to get rid of them entirely will make a noticeable difference to the end product. You can fix a lot of things in editing, but an annoying echo isn’t one of them.
Thick carpets, drawn curtains, and soft furniture are all excellent echo absorbers. That’s why I prefer to record podcasts at home, rather than in the austere surroundings of your average office.
3. Record Separate Channels
If you plan to podcast alone you can skip this one, but for my money the best podcasts are conversations. If you will be speaking with your co-hosts (and guests!) over Skype, you may be tempted to use software like Pamela to record the call as a podcast.
The problem is that sound quality takes a big hit when your voice is transmitted over a Skype call, so podcasts produced this way tend to sound uneven, with one voice sounding a lot better than the others.
The ideal approach is to get each person participating in the podcast to record his or her own audio on his or her own computer, and then edit them together after the fact.
Audacity is an excellent, free program that anyone can use to produce a good-quality recording. Whoever edits the tracks together will need to invest in multi-track recording software, however. Amadeus Pro is a nice, affordable multi-track option on the Mac. The real pros use pricey software like Adobe Audition.
4. Stereo or Mono?
If you go to the trouble of recording each of your participants separately, you have the option of balancing the voices at different spots in the stereo field.
For example, you might pan one voice slightly to the left (so that it’s a little louder in the left ear than in the right ear), and the other slightly to the right. This can make the conversation easier to follow (if only subliminally), without requiring the listener to have both earbuds in to hear both voices.
The downside of stereo separation is that you have to publish your podcast as a stereo audio file, which makes for a significantly larger download. Consider your audience (and your hosting bill!) before you make the leap to stereo.
Good audio editing software (including all the titles mentioned above) will have a compressor feature—and not the kind of compression that makes files smaller.
In the audio world, compression is a filter that reduces the volume of the loud parts of your podcast so that they are closer to the volume of the quiet parts of your podcast. Compression is arguably the easiest way to make a recording sound more professional after it’s on your hard drive.
It’s worth doing some reading (or listening to a podcast or two) on compression to really understand how it works. If you use too much compression, you’ll crush the life out of your sound. If you use too little, your sound won’t have that professional touch.
Once you’ve compressed your audio, you need to normalize it. Normalization boosts the volume of your audio so that it uses the full volume range of which speakers are capable. If you forget to normalize, your listeners will need to crank up the volume to hear you properly!
Because compression followed by normalization first pushes the louds and softs of your podcast together and then stretches them back out again, you can lose some sound quality in the process. If your audio editing software supports it, convert your 16 bit audio to 24 bit before going through these steps. Although few listeners can hear those extra bits, they will save a lot of the detail that would be otherwise lost.
When you’re done fiddling with your audio, you should convert it back to 16 bit in preparation for output as a finished MP3.
7. Export to MP3
Although some podcasts offer fancier file formats, an MP3 version is mandatory, and is often all you need. We discussed the choice of mono or stereo output above, but there are a couple of other decisions to make when exporting to MP3.
The bitrate of an MP3 directly controls the quality of the sound. The higher the bitrate, the better it will sound, but the larger the resulting MP3 file will be. If your podcast is mostly voices, a bitrate as low as 96kbps (64kbps for mono) will sound pretty good. For a podcast where frequent music needs to sound really good, a bitrate as high as 192kbps (128kbps for mono) could be justified.
You can also choose constant bitrate or variable bitrate (CBR or VBR) compression. A variable bitrate can make complex portions of your show sound better without taking up a lot of extra space for the simpler parts. Constant bitrate compression can be more wasteful, but offers better compatibility with cheaper MP3 players. Unless achieving maximum quality with minimum file size is especially important to you, I recommend sticking with CBR.
8. Tag it!
This is a pet peeve of mine. Find some software for setting MP3 metadata (commonly known as ID3 tags), or just use iTunes. However you do it, make sure the following is embedded in your file:
- Track number: the episode number of your podcast.
- Title: the title of the episode.
- Album: the name of your podcast.
- Artist: your name, or your company name.
- Genre: set it to Podcast.
…and if you really want to look good, take the opportunity to add an image as the album artwork for the episode. Typically, this would be your podcast’s logo.
Do all that, and you should have a pretty solid podcast on your hands. Now you just have to publish it! In two weeks, I’ll be back with my podcast publishing tips.
In the meantime, leave a comment with your tips for producing a great sounding podcast!