Preparing Music and Narration for AV s Software Used: Audacity (Open Source Sound Editor) Notes by Brian Gromett
Analogue to Digital Sound
Audio File Formats There are may different ways of storing audio data but generally speaking the only ones we need to consider are: WMA, WAV and MP3 WAV - Commonly used for storing uncompressed (PCM), CD-quality sound files, which means that they can be large in size around 10 MB per minute. WMA - Windows Media Audio format, created by Microsoft. Designed with Digital Rights Management (DRM) abilities for copy protection. MP3 - MPEG Layer III Audio. Is the most common sound file format used today. File sizes vary depending on the Sample Rate (128 Kbps to 320 Kbps) the lower the value, the smaller the file size but the lower the quality. But at lowest quality they take up 1/10 of the space of WAV files.
Audio File Formats and Disc Space Music Track Peter Gunn 3.49 MP3 @ 128kbs 3.48MB MP3 @ 320kbs 9.6MB WMA @ 128kbs 3.5MB WMA @ 192kbs 5.2MB WMA (Lossless) 25.6MB WAV (Lossless) 38.5MB OGG 4.59 MB 128 kbs is considered the "sweet spot" for MP3
Open Source Software Audacity can be downloaded for free from http://audacity.sourceforge.net/ If you want to Export as MP3 files you will also need a CODEX called LAME available from http://www.freecodecs.com/download/lame_encoder.htm This codec is also free
Tracks cannot be Imported direct from CD Formats WAV, WMA, OGG and MP3 are acceptable for Import but not all other formats Export formats are the same but MP3 s need an additional Codec (LAME)
Loading Tracks into Audacity To load an initial track do:- File > Open A better method of working is to use File > Import > Audio Open always creates a new project, Import adds to current project
Main Toolbars for Audacity Transport Toolbar Record Pause/Restart Play Stop Rewind Fast Forward Selection Tool Tools Toolbar Envelope Tool Zoom Tool Time Shift Tool Draw Tool Multi Tool
The Selection Tool Zoom In Drag closer to Start of beat
The Envelope Tool Music Volume Reduced for Narration Fade In Click on Blue Line to form a Handle Drag Handle down to reduce Volume Click on Handle and drag to change Volume Click on Handle and drag up to discard Handles
The Zoom Tool Select Zoom and Drag Over the required area Selection Fits the Screen
The Time Shift Tool With Time Shift Tool selected Click on Sound and Drag to new position
Some Other Useful Tools Cut Tool Copy Tool Paste Tool Trim Tool Silence Tool Zoom In Tool Zoom Out Tool Fit Selection Tool Fit Project Tool Do and Undo Tools
Saving Tracks from Audacity Saving your work with Save Project (As) will keep all of the tracks available to continue editing at a later date (like saving your Photoshop files as PSD to preserve Layers) To save your work as a single stereo recording you need to use Export and select an appropriate format from the dropdown list (like with Jpeg files all tracks / layers become unavailable for later editing)
Audacity Demonstration Opening Projects and Tracks Manipulating tracks Saving Tracks and Projects
Recording Audio with Audacity Pink for Microphones Green Speakers Blue Line In (e.g. Record deck/cassette deck Device Tool Bar Mixer Tool Bar Meter Tool Bar
Adding Narration in Audacity Various kinds of microphone are available Desk Top Headset Professional Hand Mic Whichever one you use try to keep the same distance from the Mic each time you record something Use a Wind Cover and a Pop Screen if possible to minimise extraneous noises particularly shssss and ptttts
Microphone Preamplifiers Some Microphones will perform much better if they have dedicated preamplifier M-Audio provide such devices that plug into the USB port
Recording Audio with Audacity Here you can see a microphone with a pop shield on a microphone stand. This is one of the possible ways of recording narrative for your AV s. Audacity allows you to Record, Edit and Enhance your narration in much the same way that Elements helps you improve your images
Setting Up A Microphone in Windows In the Windows Control Panel select Hardware and Sound
Setting Up A Microphone in Windows In the Hardware and Sound Panel select Manage audio devices
Setting Up A Microphone in Windows In the Windows Sound Panel select the Recording TAB, click on the Microphone and then click Properties
Setting Up A Microphone in Windows In the Microphone Properties Panel select the levels TAB Talk into the microphone and watch the Meter beside the Microphone in the Sound Panel. Now adjust the Microphone Boost and Level to make sure you don t overload it.
Microphone Settings in Audacity In the Audacity Device Tool Bar make sure that the Input Device is the Microphone you have set up in Windows Decide if you want the recording in Mono or Stereo and set accordingly Check the Microphone Level by clicking on the Microphone symbol in the Audacity Input Level Tool Bar and select Start monitoring Adjust the Level with the Microphone Level Slider
Recording Narration..
Improving Audio with Audacity Noise Reduction is used to remove hiss and hum from discs, tapes and recorded narrative. Equalization is boosting or reducing the levels of various frequencies in a signal. At it's most basic, equalization can mean turning the bass/treble controls up or down. Compression is reducing the dynamic range of a signal. All signal values above a certain adjustable threshold are reduced in gain relative to lower-level signals. This creates a more even signal level, reducing the level of the loudest parts. Reverb is used to make a voice or instrument sound more natural
Improving Audio with Audacity Before Using Equalisation After
Improving Audio with Audacity Before Using Compression After
Improving Audio with Audacity Track Duplicated and Selected Using Reverb Reverb copy with volume at -6 db Reverb Applied to Bottom Copy
The Audio Track Panel Mute Button Sample Rate Solo Button Volume Control Stereo Placement
Audacity Demonstration Setting up microphones in Windows Setting up microphones in Audacity Recording Narration and adding to it Tweaking narration NR/EQ/Comp/Revrb
Recording Vinyl with Audacity This Record Deck is a USB Deck and uses i-tunes software for storing audio but Audacity can be used by selecting the USB Codec option in the Device Toolbar. The Cassette Deck is connected to the Record Deck. Software with the deck records audio and sorts it into single tracks. It does need Album, Artist and Track Titles adding each time. Alternatively a Record Deck and a Cassette Deck could be connected to an Amplifier and then via a Line Out to the Line In connection on the Computer Sound Card. This system would use Audacity as the recording software, but each track would have to be extracted by using cut and paste.
Cleaning Up Old Vinyl Recordings An old EP Record digitised showing NOISE at the beginning on the left and between tracks on the right
Cleaning Up Old Vinyl Recordings Noise comprises of Clicks and hiss Clicks appear as sharp spikes Remove Clicks first by using Effect > Click Removal
Cleaning Up Old Vinyl Recordings Above left BEFORE Click Removal, below AFTER To remove Noise it is necessary to first Sample it and then remove it Use Effect > Noise Removal and Get Noise Profile and the repeat, Preview and OK Above right BEFORE Noise Removal, below AFTER
Scratch Removal from Vinyl Scratches appear as tall spikes The Scratch magnified Using the Draw Tool Straighten the wave form Virtually NO scratch
Using Change Tempo to Adjust Track Length You can shorten or lengthen a track without affecting the overall sound. + % will reduce the time and - % will increase the time. I prefer to use the Length (seconds) to create a track of the appropriate time to match my slide timing.
Audacity Demonstration Cleaning up a old Vinyl Recording Click and Noise Removal Scratch Removal using Pencil Adjusting Track Length with Tempo Change
Setting Up External Editors for ProShowGold Do: Edit > Preferences > External Editors For Image Editor Browse and locate Photoshop Elements For Sound Editor Browse and locate Audacity For Video Editor Browse and locate Photoshop Premier Elements
Adding Narrative to Your AV Recording your Narrative is one problem, getting it to happen at the correct time is another problem. One possible solution is to view the AV and record your script in real time. However this does make revisions quite hard. Another solution is to record each phrase individually in Audacity and then attach it to the particular slide it refers to. It is better to record everything in one take and then use Export Selection to save individual phrases ready to be attached to individual slides.
Adding a Sound to a Slide in ProShowGold In Slide Options select Sounds then click on Select Sound and find the appropriate Narration/Sound FX. You can adjust where within the slide the sound happens using the Offset. Both + and values are acceptable
Adding Sound Effects in ProShow Gold In Slide List View we can see the Soundtrack wave form in Green and the Sounds or Narration wave form in Red and we can see where they are relative to each slide. Notice the Speaker on Slides with sounds attached. In Timeline View we again see the Soundtrack wave form in Green and the Sounds or Narration wave form in Red and this time we can see them attached to a slide Hold down the CTRL Key and Sounds and Narration can be dragged about
Audacity Demonstration Setting up appropriate Editors in ProShowGold Adding Narration/Sound FX Slide List and Time Line View of Audio