The format for your podcast determines the technical setup of your studio. Some people want to record while mobile. Most people podcast in front of a single computer with a single microphone and mix in sounds from other applications, such as iTunes, Skype, and iChat. In this excerpt from Take Control of Podcasting on the Mac, we’ll focus on the hardware side of things.
Choose a microphone and supporting hardware
The only truly essential tools for podcasting are a computer and a microphone. A breakout box designed to provide external inputs of various kinds, including those used in more traditional audio, may be a helpful addition. Some podcasters find an external mixer useful for controlling multiple sound inputs as well. Let’s start with the mic, and then decide on a breakout box or mixer.
Pick a mic
For podcasting, two types of microphones are important: a directional mic, which records sound from one specific direction, and an omnidirectional mic, which picks up sound in all directions.
Directional: This kind of mic, sometimes called unidirectional, filters sound from all areas except for one primary direction. Directional mics are great for general speech because you can focus them on your voice and make many nearby sounds, including your computer’s fan, not as intrusive. But directional mics can be a liability: for example, in an interview, each subject or speaker would need his or her own directional mic. Also, directional microphones are generally more likely to distort wind noise, plosives, and sibilants.
Omnidirectional: An omnidirectional mic works well for recording ambient sounds outdoors, such as when you create a “soundseeing” tour. It’s also good for an interview if you have only a single mic. However, omnidirectional mics pick up surprising amounts of sound from all around, including room noise, computer fans, traffic, and chair squeaks.
Pick a price: Microphone prices range from cheap to astoundingly expensive. The main difference, of course, is sound quality. Low-end mics pick up only the most basic sounds and provide adequate, but not great, sound. Higher-end mics capture a much wider spectrum of sounds. For my home studio, I used to use a simple headset mic that retailed for $12 and was perfectly happy with the sound. More recently, I bought a $120 Sennheiser e835 directional microphone, and I just love how much richer my voice sounds. Ultimately, you need to decide what sound you want for your podcast.
To learn more about choosing the right mic, read the excellent article What Microphone Do I Get? by Jeff Towne at Transom Tools. The article offers great detail about types and uses of different microphones.
If you can get a mic with a windscreen—a foam shield that covers the mic—that helps a great deal in preventing plosives or wind noise when used outside.
Tip: Some people swear by a windscreen variation made by stretching a piece of nylon pantyhose over a hoop in front of the mic. These can be made easily and are available commercially—they’re often called pop filters or popper stoppers.
The subjectivity of sound
“Great sound” is highly subjective. What one person hears as fantastic may sound terrible to another. Some people prefer the sound of vinyl LP albums to CDs. Other people think that Apple’s encoding of songs in the iTunes Store sounds great (I’m one of them), but others find it unacceptable and prefer CDs. (Of course, a CD itself is usually of lower quality than a master recording.)
When I write that something produces great sound, I mean most people would agree that it sounds good to them. Some people will never accept the quality of any compressed format. When I write that something sounds bad, I mean that I can identify certain characteristics that most people would agree reduce the sound quality. The audio may be noisy with hisses or strange high-pitched warbles, or it may have odd noises like loud pops or static. Great sound starts with audio that is free from these defects.
Once, in desperation, I employed the mic on my digital camcorder to interview someone in the same room. For my tastes, the audio quality was excellent, but it is possible that a professional would cringe at it. As always, you need to decide what level of quality you desire. Or, more to the point, you need to decide what your listeners will enjoy.
Ideas for choosing a mic
I had a tough time deciding on a mic for mobile podcasting. I got a great deal of help (and mics to try) from my friend Jim Van Verth, host of The Vintage Gamer who, along with his wife Mur Lafferty, does plenty of mobile podcasting. They both use iRiver portable recorders, but with very different mics. He uses the Giant Squid, and she uses a more professional mic that is double the price. He and I discussed the pros and cons of both at length in an episode of the companion podcast to this book, Take Control of Podcasting on the Mac: The Podcast. The podcast also includes clips of interviews he and Mur have conducted using both mics.
If you want to ramp up to more expensive professional tools, you can find other hardware appropriate for advanced podcasters, including a breakout box and even a mixer.
Breakout boxes: A breakout box—or external interface—puts audio-in and audio-out jacks for your computer in a convenient form factor—a separate box—which keeps you from messing with the back of your computer when you want to plug or unplug audio gear. This is especially useful with computers that you’ve located far away from your workstation in order to reduce noise. More importantly for some people, breakout boxes typically handle analog-to-digital (or AD) conversion—turning an electrical signal on a wire to the ones and zeros computers process—separately from your computer. This usually means less noise is introduced during conversion, since the breakout box isolates the process from components that cause interference, such as hard drives. Also, external interfaces can use higher quality converters than those built into your Macintosh—and, although Apple does better than some manufacturers, it doesn’t take much to improve on the AD converters in a typical computer.
Breakout boxes often provide jacks for advanced audio, like a connector that accepts a professional microphone plug (commonly known as an XLR connector), often contain pre-amps to boost a microphone’s signal, and often enable users to record more than two tracks simultaneously. Breakout boxes are also handy for people who do not have a sound-input port on their computer. Many breakout boxes send audio to your computer using USB or FireWire. Survey your equipment to make sure a breakout box supports the options you need, as their inputs and outputs vary.
Tip: A plug is the male end of a cable and a jack is the female receptacle, usually a connector on your computer or on an external device such as a breakout box. Generally, a microphone plugs into a jack.
Mixers: Like a breakout box, an external mixer provides inputs and output jacks, but it also allow you to manage multiple input devices, control each device’s volume and equalizer settings, and combine the sources in a single stereo (or mono) signal. For example, if you have more than one microphone because you have multiple people speaking, or want to record audio that is not already on your computer but on another device, then you may want a mixer to bring these different sources together into your computer. Most multi-channel breakout boxes and external interfaces can function as mixers in combination with software on your computer. If you are all alone and all audio is coming from your mouth to your computer, then you do not need a mixer.
Mics, breakout boxes, and mixers
Some condenser microphones require the use of phantom power, electricity that runs along the same wires the audio signals travel on, which can be provided by a mixer or preamplifier. For all practical purposes, these mics don’t work if they’re plugged directly into a computer. (Get more information on phantom power.)
Unless your podcast comprises your voice and no other sound, you need a software-based mixer to handle mixing your voice with other audio on your computer.
For this excerpt’s purposes, I limit discussion of breakout boxes to the $20 Griffin iMic, a simple and inexpensive adapter that digitizes audio on a single 1/8-inch stereo input and carries it over a USB connection. The iMic is a good option for Macs with no analog audio input port. (Most have them, but laptops have notoriously bad ones.)
Otherwise, you can connect a mic with a 1/8-inch jack directly to your Mac. You can use adapters to plug in mics with a 1.4-inch jack (or even an XLR connector) to your Mac’s (or an iMics’s) 1/8-inch jack, but if your mic requires phantom power, you’ll need a suitable breakout box, mixer, or pre-amp.
Take your show on the road
Many podcasters like to take their show on the road, bringing their setup to do an interview face to face outside their home studio. Others like to conduct “soundseeing tours” by walking through a place and narrating what they see and hear. Mobility can be an exciting way to spice up a podcast.
Some people rig complicated setups where they carry a laptop and record directly to disk as they walk around. This is can be risky given that moving a laptop while data is being written to a traditional hard disk can permanently damage the drive. (Flash-based solid-state drives—or SSDs—now available as pricey options on some laptops don’t suffer from this vulnerability.) Other podcasters use small devices such as Sony MiniDisc recorders—common among print reporters—for recording interviews (though these, too, are susceptible to damage from being jostled while recording).
Many podcasters recommend iRiver audio devices, so I bought one. For $80, I bought the iRiver iFP-790, a 256MB flash-based player that records directly to MP3 format for more than 2 hours at the highest quality setting, which is more than sufficient for my needs. Interestingly, modern products from iRiver no longer work with simple microphones for capturing audio and many podcasters look for older models such as mine on eBay. Make sure you confirm that a given model will work with your microphone before buying.
Starting with the third-generation (3G) models, full-size iPods can record audio using third-party add-ons plugged in to a dock connector. The third- and fourth-generation models, however, record at a lower quality than I recommend for podcasting. Starting with the fifth-generation (5G) video iPod, Apple bumped up the recording quality to the dynamic range and depth of compact discs—although that doesn’t mean you should expect material recorded on 5G iPods to sound like professionally mastered CDs. At this time, you can install applications for voice recording on the iPod touch, iPhone, and iPhone 3G, but the quality is mediocre at best.
For the 5G iPods and 2G iPod nanos you can use the $50 iTalk Pro from Griffin Technology; for the 5G iPods, iPod classic, and iPod nano you can use Belkin’s $70 TuneTalk.
Expenses can add up quickly if you need both a portable and stationary studio setup. Here are some suggestions for keeping your costs down:
Use your portable studio for everything: Many podcasters do just fine with a simple recording device, a good-enough mic, and little else. You can record the bulk of your audio in the field or in your home studio and than transfer the audio to your computer and do your final mixing there. The downsides to this approach are that inexpensive, small microphones you might be willing to risk in the field usually offer lower audio quality. The Giant Squid mic that I use is good for field work where I like the ambient sounds (birds, cars, background noise in a café, and so on), but awful for my basement home studio with the air system, echoes, and dehumidifier. I much prefer a higher quality, highly directional microphone for my at-home work.
Use a high quality microphone with a digital recorder: You can get around the issue above by using a high quality microphone. However, you again may run into problems. First, many high quality microphones are delicate and not suited for field work. Second, a good home studio mic is likely highly directional to avoid room noise, but conducting man-on-the-street interviews is exceptionally difficult with a highly directional microphone because it involves a lot of back-and-forth between two speakers and if your aim or distance is just a bit off you won’t pick up your subject (or yourself) very well. Some high quality microphones can switch between directional and omnidirectional. Shop around and you may find something that meets all your needs in one unit.
Put the effort into your home studio and use a cheap tape recorder for field work: There’s no law that says your podcast must be 100 percent digital end to end. If you have an old memo recorder, consider using that for field work and then connect the line out or headphone output to your computer using the correct cables and capture the audio. It takes longer (an hour of recording will take an hour to digitize) but will get the job done.
Buy an all-in-one digital recorder: Some digital recorders have excellent built-in mics. Although these may not be as inexpensive as some of the items I list above, you may find they’re worth the cost for extensive field work. Some popular choices include the Samson Zoom H4 and the Edirol R-09HR.
I suggest that you begin with the least expensive setup for what you need. Unless you are a professional audio engineer (or aspire to be one), there’s no reason to break the bank. You can always start out modest and then slowly upgrade as your show gains popularity or your own interest grows.