Information about Computer Microphones and Speakers

When you are considering what type of microphone to use to record audio narration, the two major choices are the common, and generally inexpensive microphones that plug into a computer's sound card and the somewhat more expensive USB microphones that provide better audio quality.

Microphones can play an important role in the use of audio, by allowing you to record your own sound clips. Different microphones have different characteristics and some of the most important are described below.

• Dynamic microphones - A dynamic microphone takes advantage of electromagnet effects. When a magnet moves past a wire (or coil of wire), the magnet induces current to flow in the wire. In a dynamic microphone the diaphragm moves either a magnet or a coil when sound waves hit the diaphragm, and the movement creates a small current.
   
• Condenser microphones - A condenser microphone is essentially a capacitor, with one plate of the capacitor moving in response to sound waves. The movement changes the capacitance of the capacitor, and these changes are amplified to create a measurable signal. Condenser microphones usually need a small battery to provide a voltage across the capacitor.
   
  

Sound Pick-Up Patterns or Directionality

How a microphone picks up sound is another important quality. The following information about sound pick-up patterns comes from A Primer on Microphones, written by Peter Elsea, and online at: http://arts.ucsc.edu/ems/music/tech_background/TE-20/teces_20.html

• Omni-Directional - The simplest microphone design will pick up all sound, regardless of its point of origin, and is thus known as an omni-directional microphone. They are very easy to use and generally have good to outstanding frequency response. 
   
   
• Bi-Directional - It is not very difficult to produce a pickup pattern that accepts sound striking the front or rear of the diaphragm, but does not respond to sound from the sides. This is the way any diaphragm will behave if sound can strike the front and back equally. The rejection of undesired sound is the best achievable with any design, but the fact that the microphone accepts sound from both ends makes it difficult to use in many situations. Most often it is placed above an instrument. Frequency response is just as good as an omni, at least for sounds that are not too close to the microphone.
   
   
• Cardioid - Named for the heart-shaped pick-up pattern, this pattern is popular for sound reinforcement or recording concerts where audience noise is a possible problem. The concept is great, a microphone that picks up sounds it is pointed at. The reality is different. The first problem is that sounds from the back are not completely rejected, but merely reduced about 10-30 dB. This can surprise careless users. The second problem, and a severe one, is that the actual shape of the pickup pattern varies with frequency. Variations of the cardioid microphone include a super-cardioid microphone, which has a tighter pickup pattern than a regular cardioid microphone--it doesn't "hear" as much sound from the sides; and a hyper-cardioid microphone, a  very specialized microphone. A good example is a shot-gun microphone. The microphone "hears" only what it is pointing at--nothing from the sides and very little from the back. 

Styles of Microphones

There are many different styles of microphones and they come in many shapes and sizes.

• Handheld microphones are (as the name suggests) held in a person's hand or may be placed in a microphone stand.
   
    
• Lavaliere microphones are usually clipped on a speaker's clothing, such as their tie or lapel. These microphones may be wired or, more popularly, wireless. Hanging microphones are usually suspended by their own cables and may sometimes be found in orchestras or choirs. 
  
  
  
   
• Shotgun microphones are often mounted on poles and pointed toward the speaker(s). These microphones may often be found when movies and television shows are being made.
  
   
• Computer microphones are becoming more popular and many computers and digital devices now include built-in microphones.
  
  
  
  
  The Basics of Computer Microphones
  Multimedia microphones are fairly simple pieces of equipment, designed mainly for game play, recording audio clips for use with computerized presentations or for use with teleconferencing software. Most multimedia microphones utilize arms or necks that are 7 to 9 inches in length, and most rest in a stand on the desktop. However, the line between a multimedia microphone and a traditional microphone is becoming more blurred. Traditional handheld microphones often can be converted to work with a computer as a multimedia microphone using a simple jack or plug. Some multimedia microphones can be worn as a mouthpiece with a headset as well, making them especially handy for voice-recognition applications. 
  
  How to Shop for a Computer Microphone
  Flexibility is one of the best features you'll find in a multimedia microphone, and it's worth paying a little extra for. A microphone with a flexible neck is going to be far more comfortable to use, no matter where you're trying to use it. If the microphone is part of a headset, the microphone should be adjustable with a flexible neck, allowing you to place it directly in front of your mouth. A microphone sold as part of a headset also should also easily disconnect from the cord so you can move around without constantly having to remove the headset. For those who need to create professional-style audio clips on their computers, investing some extra money in a traditional handheld microphone and converting it for use with multimedia applications will be worth the added cost. While multimedia microphones are solid performers, they can't compete in quality of audio with traditional microphones. 
  
  Where to Buy a Computer Microphone
  Because multimedia microphones are so inexpensive--usually ranging anywhere from $5 to $20--you won't have to search too hard to find some good deals. Any store that carries a collection of computers and PC peripherals should have plenty of brands of multimedia microphones from which to select. Probably the best combination of price and selection will come from an online retailer, such as Amazon.com, NewEgg.com or TigerDirect.com; or an electronics store, such as Best Buy or Office Depot. Radio Shack is also a good source for inexpensive microphones. Because multimedia microphones are so inexpensive these days, repairing them usually is a waste of effort and money, so the store's service center isn't overly important. If you plan to record a large number of  audio clips for integration into PowerPoint presentations or web pages, you may want to look into buying a professional-style microphone. In this case, you will spend more and you may want to search the web for microphone manufacturers, or you can visit a music equipment store. Before purchasing, though, make sure the microphone you choose can be used with a computer. You may need to buy additional jacks or plugs at a computer equipment store or from the microphone's manufacturer to make certain it connects properly to you computer.

IMPORTANT NOTE:
The sound quality of your recorded audio is fair when using this type of microphone, however, the quality of your computer's sound card will also affect the quality of the recording at least as much as the model of microphone you are using.



The cable shown here has a metal tip called a mini-plug on one end. The other end is wired directly into the base of the microphone. The plug end is called the male end, and is one eighth inch in diameter, so sometimes you may hear this type of connector called a 1/8th inch connector. This type of connector is often used for audio and is frequently found on older, less expensive microphones (like the one shown above) as well as on headphones that can be plugged into a computer, smartphone or portable audio player. A single stripe seen near the end of the metal plug indicates that this is a monaural cable, while two stripes indicates that this cable supports stereo sound.

USB Microphones

USB microphones utilize a USB cable that connects directly to a computer, bypassing an internal sound card.



These USB microphones generally better sound quality than the older microphones that use a mini-plug to connect to computers, as described above. This is because USB microphones usually include an internal analog to digital coverter that modifies the signal from your voice being recorded by first amplifying it and then conveting it into a digital format, and finally sedning it over a USB cable to the software you are using, such as PowerPoint, Audacity, etc.

If you plan to do a lot of audio recording and/or you are interested in very high quality audio, the following more expensive desktop USB microphones offer significantly better sound quality than the less expensive models.

Approximately $70	Samson C01U Microphone Available from Amazon: http://www.amazon.com/Samson-CO1U-USB-Condenser-Mic/dp/B000AP1RE8/ref=sr_1_1?ie=UTF8&s=musical-instruments&qid=1222788296&sr=1-1
Approximately $130	Audio Technica AT2020 Available from Amazon: http://www.amazon.com/Audio-Technica-AT2020-Cardioid-Condenser-Microphone/dp/B0006H92QK
Approximately $80	Samson GM1U G-Track http://www.amazon.com/Samson-Track-Microphone-Audio-Interface/dp/B0015MJE22/ref=sr_1_fkmr0_1?ie=UTF8&qid=1266268312&sr=1-1-fkmr0
Approximately $130	Blue Yeti http://www.amazon.com/Blue-Microphones-Yeti-USB-Microphone/dp/B002VA464S/ref=sr_1_1?ie=UTF8&s=musical-instruments&qid=1266268730&sr=1-1
Approximately $230	Rode Podcaster http://www.amazon.com/Rode-Microphones-Podcaster-USB-Microphone/dp/B000JM46FY/ref=sr_1_1?ie=UTF8&s=electronics&qid=1247407553&sr=1-1

When you first plug a USB microphone into a PC, you may need to change some audio settings to make sure the computer recognizes the microphone. In the Windows 7 operating system, you should first go to the Start menu and click on Control Panel.

Depending on how your Control Panel is configured, you should follow these steps.

Option 1: If the Control Panel is in the Large icon view, click on the Sound icon.

The Sound dialog box should now be displayed, as shown here. If it is, skip Option 2 and continue reading after that (where it says Continue Reading Here).

Option 2: If you are in the Category view, click on the Hardware and Sound link.

This will bring up several Sound options. Click on the Sound link OR the Manage audio devices link.

Click on the Recording tab at the top left of the window.

Continue Reading Here:

If your microphone is connected properly, it should appear in the list. In this example, you can see that an Audio Technica AT2020 microphone is properly installed. You should try speaking into it to see if the volume is set properly. The more green bars you see as you talk, the higher the volume.

Unfortunately with the Windows operating system, when microphones are first connected, the recording volume may be set to a very low level.

You can check this by clicking one time on the microphone in the Sound dialog box to select it and then clicking on the Properties button.

The Microphone Properties dialog box should now be displayed. Make sure that this device is enabled and use the pull-down menu at the bottom of the box to enable it, if needed.

Click on the Levels tab and you should now be able to see a numerical value that the microphone's recording volume is set to, such as "17" in the example below.

You should move the slider bar to a higher recording volume level and I suggest a setting of 75 or 80. You may need to try a few test recordings at different volume levels to find out the best setting for your microphone and computer.

You should also click on the Advanced tab to increase the audio recording quality. I recommend that you try any of the CD or DVD quality settings and make a test recording. Then listen to the results to determine which sounds best. Please note that 1 channel usually refers to a monophonic recording and 2 channel refers to stereo recording. When you record your voice for use in a PowerPoint presentation, you will not usually be able to tell any difference in the sound of the narration regardless of whether you select 1 channel or 2 channel recording.

When you first plug a USB microphone into a Mac, you may need to change some audio settings to make sure the computer recognizes the microphone. In the Macintosh OSX operating system, you should first go to the dock and click on the System Preferences icon.

If you do not see this icon, you can use the built-in Spotlight search tool on your Mac. Look for the magnifying glass icon and type in the term: "system preferences" and it should be found.

You should now be able to launch the System Preferences which will open a dialogue box, as shown below.

Locate the Sound icon and click on it. This will open the Sound preferences dialogue box.

Follow these steps:

1. Click on the Input tab. If your USB microphone is connected to your Mac and has been installed properly, it should show up in the list of devices.

2. Click on the microphone's name to select it and begin talking.

3. If the microphone is working, you should see the Input volume level indicator moving to the right as you speak. You can drag the white slider bar to the right or to the left to increase or decrease the recording volume level of your microphone, as needed. A good rule of thumb is to set the level so that the it is somewhere between 50 and 75%, although you should always make a test recording so that you can determine the best level for your particular microphone.

4. You may also need to adjust the Output volume level of your speakers, headphones, or headset to a comfortable listening level.

A Few Words about Computer Speakers

Since creating, editing and viewing digital media projects generally involve audio, you may need to consider adding external speakers to the computer where you are doing your work. Most computers come with a sound card already installed and at least one small internal speaker, which allows audio to be played. However, you may need to add a separate set of speakers or a pair of headphones so that narration, music and special audio effects can played at a volume level loud enough for you to make recording and editing decisions. Almost all speaker systems that can be added to a computer require some power source, which may be from batteries, plugging the speakers into an electrical outlet, or in some cases, getting power from the computer via either a USB or Firewire cable.

There are many different options when it comes to adding external speakers to a computer and three popular choices are shown below:

A simple pair of powered stereo computer speakers.	A pair of stereo speakers with an added subwoofer for increased bass response.	A 5.1 channel surround sound system includes speakers for the front (left & right) rear (left & right), center channel (for dialogue) and a subwoofer.

This page was last updated on July 18, 2017.