Using Audacity: Preparing the Computer to Record Sound


Turn off Unnecessary Programs


Recording sound, as well as processing and editing audio files requires a lot of computer power. The more available memory your computer has, the less likely the audio recording will be interrupted and the faster any processing of audio files will occur. Turn off all unnecessary programs to free up memory and to ensure smooth running of the recording software.
Also, turn off anything that could create a sound while you are recording, especially programs that can give alerts such as email programs, instant messaging etc.

Connecting & configuring a microphone to a computer


One very simple way to record audio using Audacity is to use a desktop or notebook computer in conjunction with a analogue or usb headset.

As a general rule it is a good idea to ensure your computer is recording and playing back audio using your chosen microphone and speakers/headphones prior to opening Audacity.

Analogue headsets


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cc licensed flickr photo by sridgway: http://flickr.com/photos/stephanridgway/259297980/

Typically analogue headsets have 2 leads, one for the microphone and one for the headphones which are plugged into the computers sound card. They are referred to as analogue as the computers sound card converts the signals to digital information. The leads follow a loose colour coding convention which is unfortunately not often adhered to, pink for the mic and green or black for the headphones. They may also have printed symbols which denote the microphone and headphones. One of the common problems with analogue headsets audio is that they are plugged into the wrong sockets on the computer.
They commonly have an in-line volume control and a microphone mute switch which is also a good place to check if you have no audio signal. The microphones fold out and need to be close to your mouth, 15 cm max to work effectively.

It is also common for microphones to be referred to as noise canceling, designed to filter out ambient or background noise from the input prior to recording. This technique uses two microphones and circuitry to remove the noise. The primary microphone, situated close to the users mouth is combined with the signal from the second mic, pointed away from the user, in such a way as to cancel out the noise.

Analogue headsets range anywhere from $7 up to $50 depending on the quality of the headphones mostly and are the most common type of headset used.

Sound card settings

Windows XP

Analogue headsets are notoriously difficult to get working as they require the "sounds and audio devices" settings in Windows to be set up correctly. As each sound card, driver software and computer is different so it is difficult to provide a definitive guide to the set-up. Once set up it will not need to be altered, however it may require some trial and error tweaking to get it right initially.

Setting Playback & Recording Levels

Having plugged the microphone into its correct socket, it is now time to set the correct recording level of the microphone in the sound card.
Every sound card has two mixing panels, one for adjusting audio playback levels, and one for adjusting audio recording levels.
Volume Levels
To access the Volume Control panel
Select: Start >Settings> Control panel > Sounds and audio devices and selct the Audio tab and click the volume button on the Sound playback section

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Or if you have a speaker icon in your task bar,right click on that and select Open Volume Control and raise the volume slider

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This control panel will enable us to hear if the playback is working correctly, adjust the volume level so you can hear sound at a sufficient level.

Recording Levels
Under Options > Properties > Recording

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Make sure the microphone slider fader volume control is all the way up, and the mute button is un-checked. Then click on the Advanced button in the Mic Volume panel.
In the Advanced Controls section, select 1 Microphone Boost (bottom left) with a tick.

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Microphones have a very small output voltage and by amplifying the tiny signal we can record at the correct audio level.

Most sound cards will only let you record one thing at a time. In this case we want to use the microphone only, so place a tick in the microphone box. Make sure the sliding fader control is pushed all the way to the top.

Close the panel and return to the main Volume Control panel.

Watch this video to learn how to use the sounds and audio devices panel.

MAC OSX

Things are easier under MAC OSX because the the hardware is a know quantity allowing for a much simplified interface. The catch with current Apple computers and notebooks such as the iMac, Macbook & MacbookPro is that they do not provide phantom power to the microphonme socket so most analougue microphones which use cheap electret condenser microphones will not work. This renders the line in socket as a Line In socket only for use with powered microphones. The current generation of MAC computers have good quality internal microphones which can be used for recording audio.

To set and adjust the microphone levels double click the Sound icon under the hardware section of the system preferences.

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Here you can choose either the internal microphone or the external Line in as the input source for the audio source and set the levels.

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Adjust the Input Volume slider while speaking into the microphone so that the level meter is peaking one bar from the max when you are speaking the loudest. It is better to be a tad low than too high as distortion is hard to fix.

Desktop Computers vs Notebook/Netbook

It's not uncommon for desktop computers to have 2 microphone headphone socket sets, one at the rear and one at the front of the computer. Plug the headset into the one most convenient. The rest of the configuration will be done using the Windows "sounds and audio devices" panel.

Notebook Computers

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cc licensed flickr photo by sridgway: http://flickr.com/photos/stephanridgway/259455132/

Notebooks often have an internal microphone in addition to a socket for an external microphone. Sometimes these are referred to mic 1 and mic 2 on the audio devices panel. When an external mic is connected the internal mic is disabled.

Notebook Internal mics are fine for doing on the fly session in Skype or Adobe Connect but are not the best option in terms of audio quality as they will pick up lots of keyboard vibration and fan noise.

USB headsets


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cc licensed flickr photo by sridgway: http://flickr.com/photos/stephanridgway/259297942/

USB headsets are fully digital in that the headset itself converts the microphone signals to digital information and hence the sound card in the computer is not utilised. The data is transferred via the USB port. One of the great features of USB headsets is that they are "plug and play" and don't require any drivers to be installed and will generally be ready to use once the operating system has detected and configured the headset. The advantage of USB headsets is that you bypass the common issues surrounding sound cards and drivers outlined above, all you need to do is plug the lead into a free USB port and ensure the microphone level is set appropriately in the sounds and audio devices panel.

They are a great option for Apple MAC computers.

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Adobe Presentation on choosing a microphone