Microphones For eLearning
Even though audio is a critical aspect of multimedia learning, many of us don’t know how to choose a microphone for audio recording at work or in the field.
That’s why I felt so fortunate to get introduced to John Tellin, who has been working with sound equipment for over 40 years. He kindly answered many of my questions about audio recording mics. I hope this interview answers some of your questions too. I added quite a few Editor’s Notes after the interview, realizing further explanation might be needed.
COACH: What is the most basic concept a beginner needs to understand when it comes to audio recording?
JOHN: I have found that the audio content of a presentation is even more important than the video. As an example, listen to (but don’t watch) a TV program for a few minutes. You’ll find that you can easily keep up with what’s happening.
On the other hand, if you mute the audio and watch the picture, you’ll usually become lost rather quickly. That’s why I think audio is so important in any kind of presentation, whether live, in-person, recorded or online.
COACH: Can you categorize the types of recording mics multimedia and eLearning producers might use for voice over recordings and workplace interviews?
JOHN: Multimedia and eLearning providers may use a wide variety of microphones, from stand mounted or handheld wired microphones to headset wireless microphones, and several other types as well. It depends on your situation.
As far as the location for the presentation, I would recommend a reasonably quiet place with good acoustics, that is, absorbent surfaces that will help keep the presenter from sounding as if she or he is in a barrel. A close microphone such as a headworn can help here. If you are not wearing the microphone, remember that if you move away from it, your audience may not be able to hear you anymore.
COACH: So your advice is to stand very close to the recording mic?
JOHN: Microphones work best when the speaker is as close as practical to the microphone. I’m not saying you should eat it like an ice cream cone, but don’t put it more than a foot away from your mouth. This helps with clarity and controlling background noise. Our goal is to provide as clear and high quality sound as possible. This will help keep the audience’s attention.
COACH: Can you explain the difference between a wired microphone and a wireless one?
JOHN: A wired microphone is a traditional one that plugs into a microphone input of a sound system through a microphone cable. There are USB mics that plug directly into any computer’s USB port.
A wireless microphone uses radio signals to transmit the sound from the microphone to the amplifier or recording machine. In most wireless microphone systems, the receivers plug into electrical outlets (for power), but they also plug into a sound system the same way a wired microphone does.
COACH: What’s the advantage of a unidirectional mic?
JOHN: Unidirectional microphones are widely used today, both by individual speakers as well as interviewers. They work well at limiting background noise.
COACH: What should someone look for when purchasing a microphone?
JOHN: As with most items we buy in today’s world, you get what you pay for. Having said that, you can get a perfectly fine wired handheld microphone for around $100.00. My personal favorite in this category is the Sennheiser E835. The Shure SM-58 is another long time favorite in this same price range. [Editor's Note: Handheld mics might be most useful for live interviews; studio mics for audio recording at work.]
Very high quality studio microphones are available for around $300.00 that will give you an even better recording. The Audio Technica AT4040 is one example. [Editor's Note: Also check out the Blue Yeti Mic and Blue Snowball Mic, which come highly recommended when you're just starting out. These run in the $100 range.]
COACH: Is it best to record into a digital recorder or will recording directly into a computer suffice?
JOHN: Either a digital recorder or a laptop or even a desktop will work fine with the proper equipment and software. If you use a computer, I’d recommend an audio recording interface that bypasses the computer’s sound card and connects directly to a USB or Firewire input on the computer.
Sound cards are not known for their quality in the industry, and an interface can significantly improve the quality of your recording, particularly with a good microphone hooked to it. These units are available starting at about $150.00. Almost all of them come with recording software that you may use on your computer.
[Editor's Note: An audio interface is a piece of equipment that handles input and output of audio from your computer. It's more than a sound card. Here's a sample of audio interface products by Behringer. Also see the Tascam products. Sorry, I don't have a recommendation.]
COACH: What other equipment might be useful? What about mixers?
JOHN: Mixers are quite useful if you want to record sound from more than one source at the same time. Depending on the number of microphones you want to use, you can get mixers for $100.00 or less that will handle two microphones plus some other sources, such as CD players, IPOD’s, etc. at the same time.
COACH: Does a microphone need special care and maintenance?
JOHN: Most microphones don’t require a lot of maintenance. If you are not going to use a wireless microphone for several days, take the batteries out of the transmitter. Be careful with lapel or headworn microphones—the fine wires that connect them to beltpack transmitters are quite fragile and are easily damaged. Try not to drop any microphone, and keep liquids away from all of them. In addition, avoid leaving wireless microphones in hot or humid environments (or in direct sunlight) for an extended period of time.
John Teelin is a Sales Consultant with All Pro Sound in Pensacola, Florida. He has worked with sound equipment in broadcasting since 1964. If you have questions, feel free to e-mail him at teelin [at] allprosound.com. Thanks for a great interview, John!
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