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1 CLASS XI Total Duration 160 minutes Learning Outcomes The learning outcomes expected by the end of the academic year are that,the students will be able to: 1. Record live audio 2. Edit audio flies 3. Mix sounds 4. Export audio files in formats as MP3, WAV. Concepts Covered Recording, Importing files, Editing, Narration, Mixing, Built in effects, Save and Export file. Content Outline Introduction and Recording Audio. What is Audacity? Why Audacity? Recording Audio Import music file Track control panel Recording more than one audio. Editing Audio Editing tools --- Select,Envelope Remove DC offset Delete silence Reduce Amplification Some more built in effects Recording and Mixing Narration with Music Record Narration Edit Narration o Leveling out volume` o Cutting the Narration track Marking start of narration in the background music Moving the narration clip to work with music Mix Saving file Saving file and Exporting audio Sources:

Introduction and Recording Audio AUDACITY What is Audacity? Audacity is a free audio recording software program Why Audacity? Audacity eliminates the need for a stand-alone audio recorder.

2 Introduction and Recording Audio AUDACITY What is Audacity? Audacity is a free audio recording software program Why Audacity? Audacity eliminates the need for a stand-alone audio recorder. If you have a computer, with either a built-in microphone or an attached external microphone, you can download the free Audacity program and begin your journey into the world of digital audio recording and editing. Ways to use Audacity You can record audio using a built-in or external microphone, or you can import an audio file to edit. You can also use a patch cable to record directly from another computer or audio source. Let s start recording This is what your screen will look like when you first open Audacity and haven t started recording. To start recording, click on the Record button. To stop recording, click on the Stop button. For editing practice, record speaking softly, then more loudly. Also, leave a few seconds of silence at the end of your recording before clicking the stop button. Your Recorded Audio After you record your audio, you will see that your blank screen has been replaced with a Track containing your audio file, and you can see the audio recording length, and audio characteristics. You can edit this recorded audio, or you can record more audio.

3 This is your recording timeline. It shows you the length of your recording in seconds or minutes/seconds. This is your Track showing the waveform of your recorded audio, and how the amplitude changes with the loudness of your recording. Recorded audio often varies in loudness, but with Audacity, you can edit the recorded audio to make it louder or less loud. You can also delete portions of recorded audio, such as recorded silence. Import the file into Audacity First launch Audacity, then import an audio file by selecting File > Import >Audio..... A quicker method is to just drag and drop the file as in the following examples:

4 Track Control Panel Controls Close Button: Clicking this button will close the track, removing it from the project. Audio Track Dropdown Menu: Clicking the track name or using SHIFT + M on the currently focused track opens the Audio TrackDropdownMenugiving options that affect this track only. Newly created tracks are named "Audio Track". Options in the dropdown menu include changing the name or sample rate, how the track is displayed, splitting a stereo track to single left, right or mono tracks and swapping stereo channels. Mute Button: Click to silence this track when playing. Solo Button: Click to play just this track. Click again to release the button. Gain Slider: Set the gain for this track. Hold down the shift key while dragging to adjust the slider in finer increments. Double-click the slider to bring up a window wheree you can make precise adjustments or enter a gain value. Pan Slider: To make signal stronger on left or right earphone. Hold down the shift key

while dragging to adjust the slider in finer increments. Double-click the slider to bring up a window where you can make precise adjustments or enter a pan value.

Recording more Audio Sometimes, you will record a segment of audio, stop, and then record more audio. To do so, click at the end of the waveform.

If you don t click at the end of the waveform, you may end up with two tracks on top of each other, which isn t good if you re recording voice.

5 while dragging to adjust the slider in finer increments. Double-click the slider to bring up a window where you can make precise adjustments or enter a pan value. Track Collapse Button: Click on this to make the track 'fold up' into a smaller size. Click again, or drag the lower edge of the track to restore the size. Recording more Audio Sometimes, you will record a segment of audio, stop, and then record more audio. To do so, click at the end of the waveform. This will allow you to start recording at that point in the timeline. Audacity treats multiple recorded tracks like transparencies. If you don t click at the end of the waveform, you may end up with two tracks on top of each other, which isn t good if you re recording voice. You now see that I have two recorded tracks, and that the second track starts where the first track ends. If you forgot to click the point in the timeline where you want to start recording, you can move the audio to a new point in the timeline. We do so with the Timeshift tool.once you ve clicked on the Timeshift tool, move your cursor onto the audio you want to move and then click and drag to the desired location in the timeline.

6 Audacity s editing tools Select Tool The default editing tool is the Selection tool that looks like an I beam. This tool allows you to click and drag over your waveform to select areas you want to edit. Envelope Tool Used to ajust the volume levels. Removing any DC offset (if present) DC offset can occur in audio files so that the recorded waveform is not centered on the horizontal line at 0.0 amplitude. It can be caused by recording with a faulty soundcard. The example above is centered on 0 correctly and carries no DC offset. Accessed by:effect>normalize...

7 When this box is checked Normalize attempts to remove any DC offset in the selection by centering the waveform on the 0.0 amplitude level. DC offset is an offsetting of a signal from zero. On the Audacity waveform it would mean that the waveform in default view appears not to be centered on the 0.0 horizontal line, as in the upper track of the above image. For example, the voltage may be directly caused by a faulty soundcard, or may come from some other device that is attached to the card. Any offset is normally so small as to not be noticeable, but with defective or poor quality hardware it may become large enough to be a problem. DC offset can cause inaudible low level distortion. The distortion may become audible when effects that change the frequency content are applied, or when exporting the audio to a size-compressed format like MP3. Delete Silence Let s use the Selection tool to select the area of silence at the end of our recording. After the click and drag, your area of silence will be highlighted. Click the Delete button on your keyboard to delete the silence.

Reduce Amplification Sometimes the recorded audio is so loud, it causes distortion to the finished audio. You can reduce the amplification.

This signifies that the recording was very loud and needs to be reduced.

After you ve highlighted your section of loud audio that you want to reduce, click Effect and Amplify. After selecting Amplify, you will see the box above.

8 Reduce Amplification Sometimes the recorded audio is so loud, it causes distortion to the finished audio. You can reduce the amplification. As you can see from the waveform below, the amplitude of a portion of the recorded audio reaches the top and bottom of the track area. This signifies that the recording was very loud and needs to be reduced. To reduce the amplification, once again we will use the Selection Tool to click and drag over the portion of the waveform that we want to edit. After you ve highlighted your section of loud audio that you want to reduce, click Effect and Amplify. After selecting Amplify, you will see the box above.to reduce amplification click and drag the slider to the left. The decibel level changes. Click OK to reduce your highlighted audio by the specified decibel level. Some Built-in effects Audacity's built-in effects (those that appear in the program irrespective of the contents of your Audacity and other "Plug-Ins" folders) are above the divider in the Effect menu. Amplify... Increases or decreases the volume of the audio you have selected. When you open the dialog,

9 Audacity automatically calculates the maximum amount you could amplify the selected audio without causing clipping (distortion caused by trying to make the audio too loud). Auto Duck... Reduces (ducks) the volume of one or more tracks whenever the volume of a specified "control" track reaches a particular level. Typically used to make a music track softer whenever speech in a commentary track is heard. Change Pitch... Change the pitch of a track without changing its tempo. Change Speed... Change the speed of a track, also changing its pitch. Change Tempo... Change the tempo of a selection without changing its pitch. Click Removal... Click Removal is designed to remove clicks on audio tracks and is especially suited to declicking recordings made from vinyl records. It will usually work best on very short clicks. For broader individual pops in selections up to 128 samples wide (about three milliseconds at Hz project rate). Compressor... Compresses the dynamic range by two alternative methods. The default "RMS" method makes the louder parts softer, but leaves the quieter audio alone. The alternative "peaks" method makes the entire audio louder, but amplifies the louder parts less than the quieter parts. Make-up gaincan be applied to either method, making the result as loud as possible without clipping, but not changing the dynamic range further. Echo... Repeats the selected audio again and again, normally softer each time. The delay time between each repeat is fixed, with no pause in between each repeat. For a more configurable echo effect with a variable delay time and pitch-changed echoes. Equalization... Adjusts the volume levels of particular frequencies. Fade In Applies a fade-in to the selected audio, so that the amplitude changes gradually from silence at the start of the selection to the original amplitude at the end of the selection. The shape of the fade is linearthe rapidity of the fade-in depends entirely on the length of the selection it is applied to.

10 Fade Out Applies a fade-out to the selected audio, so that the amplitudechanges gradually from the original amplitude at the start of the selection down to silence at the end of the selection. The shape of the fade is linear. The rapidity of the fade-out depends entirely on the length of the selection it is applied to. Leveler... Leveler is a simple, combined compressor and limiter effect for reducing the dynamic rangeof audio. It reduces the difference between loud and soft, making the audio easier to hear in noisy environments or on small loudspeakers. It is best suited to speech recordings but at heavier settings or used multiple times it can also be used as a simple distortion effect for voices or instruments. Noise Reduction... Reduces constant background noise such as fans, tape noise, or hums. It will not work for removing talking or music in the background. Normalize... Use the Normalize effect to set the maximum amplitude of a track, equalize the amplitudes of the left and right channels of a stereo track and optionally remove any DC Offset from the track. Narration Recording and Mixing a Narration With Background Music The objective is to record a simple narration, add some background music, cut the narration to fit the music, lower the volume of the music during the narration, and finally mix and export the final product. Record the narration Consider where your microphone is going to be in relation to everything else in the room. Try to place it so that it picks up a minimum of computer noise (hard drives, fan). When speaking into the microphone, point the microphone at your mouth but don't point your mouth at the microphone. Setting up the microphone so that it is level with your mouth but a little off to the side also works. This avoids "popped p's" and other breath effects from ruining your recording. Finally, try to set up the microphone so that it is 4 to 6 inches away from your mouth. While you are talking, try to keep looking in one direction - moving your head left or right, up or down, while you're talking will change the tonal quality of your voice, and may be distracting to your listeners. Speak in a normal, conversational tone of voice, but also speak clearly and enunciate

11 carefully. NOTE: If you have just made a recording it is strongly recommended to File > Export Audio.. it immediately to WAV or AIFF (ideally to an external drive) as a safety copy before you start editing the project. Perform a level test of your voice before it is recorded for real. Click on the downward pointing arrow in the Recording Meter and click "Start Monitoring". While speaking into the microphone as loudly as you intend, adjust the recording level slider (by the microphone symbol) on the Mixer Toolbar so the Recording Meter is almost reaching the far right-hand side (but not far enough to bring the red hold lights on). If the Recording Meter is not visible, click on View > Toolbars and enable the Meter Toolbar. Edit the narration Don't edit too tightly - the final result should sound natural. Use Audacity's Cut Preview feature to hear how each edit will sound before you make the edit. Then listen back to each edit - undo and try again if it doesn't sound natural. Leveling out the volume Unless you are professional narrator or voice-over specialist there are probably level (volume) variations during your narration. Remember, your listeners can't see you, so having a consistent volume for your narration is important so they'll be able to hear and understand everything you're saying. You could go through and manually adjust the volume throughout your narration track using the Envelope Tool, but there's an easier way - use Audacity's built-in Compressor effect. Click on the Track Control Panel of your narration track to select the entire track then choose Effect >Compressor. The Compressor effect works by making the loud parts quieter, then amplifying everything, which ends up making the quiet parts louder. Check Make-up gain for 0dB after compressing and Compress based on Peaks. The former means that Compressor will maximize the volume of the track after it does its work. The latter means that Compressor will look at the peaks of the waveformrather than its average value. The "Threshold" control is the "tipping point" - the point where Compressor decides if something is "loud" (and should be made quieter) or "quiet" (in which case it leaves it alone). The "Noise Floor" control tells Compressor that anything below that level is noise and it shouldn't make it any louder.

12 The "Ratio" control tells Compressor how much quieter it should make the loud parts. Set the "Attack Time" to "0.5 secs" Set the "Release Time" to "1.0 secs". These two controls tell Compressor how fast it should respond to changes in volume. Note that once you've gone through setting everything up the first time, on subsequent tries you just change the Threshold. This make it easy to home in on the setting that works. Import the background music file Choose File > Import > Audio and open the background music file you've chosen for the project. Audacity imports the music file into your project and puts it in its own stereo track. Look at the Track Control Panel at the left of each track. Note the "Mute" and "Solo" buttons. You can use these to control which tracks you hear when you click the Play button. Clicking the "Mute" button will turn that track off. Clicking the "Solo" button will cause only that track to be heard when you press the Play button. Cutting the Narration Track (Time-shift the tracks ) Start by clicking the "Solo" button on the narration track - we don't want to listen to the music track while we're doing this work on the narration track. Assume that we want to cut the narration into three separate segments. Each of these segments will begin when the music makes a dramatic change. Find the spot between the first and second portions of the narration. Using the Selection Tool click at this point. Choose Edit > Clip Boundaries > Split - a split line appears. There are now two clips on the narration track. Similarly, put a split point between the second and third portions of the narration. The narration track will now look something like this: Marking the places in the background music track where you want the narration clips to start Remember, our goal is to cut the narration to fit the music. So our next step is to pick the spots in the background music track where we want the three narration clips to start

13 Click the "Solo" button on the narration track to turn off the Solo function on that track. Click the "Solo" button on the background music track so you will only hear that track. Identify the point in the background music track where you want the narration to begin. Click at that point with the Selection Tool. Choose Tracks > Add Label at Selection. Type a name for the label, for example "First Narration". Similarly, identify the points in the background music track where you want the second and third narration clips to begin, and create labels at those points. Moving the clips to work with the music Click the Solo button on the background music track to turn off the Solo function on that track, so we can hear both the narration and music tracks. Using the Time Shift Tool drag the third narration clip so that the start of the clip lines up with the third label. Audacity will help you line this up perfectly - when the start of the clip lines up with the third label a yellow BoundarySnapGuidewill light up. Similarly, drag the second narration clip to line up with the second label, and drag the first narration clip to line up with the first label.

14 Adjust relative volume levels There are at least two ways to do this: manually with the Envelope Tool, or automatically with the Auto Duck effect. Using the Envelope Tool Select the Envelope Tool from the Tools Toolbar. In the music track, click to create a control point a second or so before the first narration clip begins. Click to create a second control point just as the narration starts. Drag the second control point down to reduce the volume of the music track. Click in the Timelinea few seconds before the start of the first narration clip to hear the effect. Press SPACE to stop playback. Adjust the first and second control points to get the length and depth of the fade you want. In a similar manner create the fade up at the end of the first narration clip.

You could continue in this manner doing the fades on the music track for each clip in the narration track. Or you could try using the Auto Duck effect.

15 You could continue in this manner doing the fades on the music track for each clip in the narration track. Or you could try using the Auto Duck effect. The advantage of using the Envelope tool is that you can always go back and change the fades. Auto Duck, being an effect, permanently alters the music track. Smooth fade of the background music click at the point where you want the music to begin fading out. Again choose Edit > Select > Cursor to Track End, then Choose Effect > Fade out. Check your mix If you maximized the volume of your narration track there is a good chance that when you mix it with the music track the resulting mix will be too loud and cause clipping - this is a bad thing. Remember, we maximized the volume and leveled out the loud and soft passages so that people would be able to hear you. To check for clipping, play back a short portion of the project where there is narration and background music. Watch the Playback Meter - if clipping occurs the red "clip bars" will appear at the right-hand end of the Playback Meter. If this happens, use the Track GainSlider to turn down the volume of both the narration and music tracks to -2 db. Listen to the short section again and look for the red clip bars on the Playback Meter. If clipping still occurs, turn down the volume of the narration and music tracks to -4 db each. Optional - Mix and Render You may want to Mix and Render your project before you export it. The Mix and Render command (in the Tracks menu) will mix your project, and put the resulting mix in a new track (this is the

16 "render" portion of the command). This gives you the opportunity to maximize the volume of the final mix, and do a final check for clipping. If you would like to try this, follow these steps: Choose Edit > Select >All Mix and Render only mixes the selected tracks - you want to mix all of them Choose Tracks >Mix and Render your project is mixed into a new stereo track and the previous, separate tracks are deleted. Saving an Audacity Project There are two main commands for saving projects: File >Save Project saves a standard project as an AUP project file (a file with ".aup" after its name) and a _data folder containing the actual audio.. File >Save Project As... similarly saves a standard project as an AUP file and _data folder. It is for saving an empty project or to save an existing Project to a new name to make a copy of the project in its current state then continue working on that copy. Saving a project lets you save unfinished work and re-open it later in Audacity exactly as it was, with all edits and recorded/imported tracks preserved. Exporting audio files To make an audio file for playing on your music player, burning CDs or for use in other programs you must use one of the Export audio commands as Audacity projects can only be opened and used by Audacity; neither the.aup project file or the.au files in the _data folder can be used in other programs or devices. Use File >Export Audio... which brings you to the Export Audio dialog where you can select from various standard audio file formats according to your purpose. The two most common formats which can be played almost anywhere are: WAV: a lossless very high quality, but large, format ideal for burning to Audio CDs. WAV files will open, play and can be edited on Windows, Mac OS/X and Linux computers. MP3: a lossy lesser quality format but small enough to send over the Internet or store on portable devices. Typically an MP3 file can be around ten time smaller than the equivalent WAV. They will also open and play on Windows, Mac OS/X and Linux computers. MP3s are good for listening and sending or website posting but are poor for editing and production.

Selection tool - for selecting the range of audio you want to edit or listen to.

Selection tool - for selecting the range of audio you want to edit or listen to. Audacity Quick Guide Audacity is an easy-to-use audio editor and recorder. You can use Audacity to: Record live audio. Convert tapes and records into digital recordings or CDs. Edit sound files. Cut, copy,