Wrking With Audacity Audacity is a free, pen-surce audi editing prgram. The majr user interface elements are highlighted in the screensht f the prgram s main windw belw. The editing tls are used t edit audi files and will be explained further belw. The transprt cntrls functin in the expected way; that is, as a tape recrder, allwing yu t play, stp, pause, r recrd audi as well as jump t the beginning r end f an audi track. The level meters shw yu the audi levels f the sund being played back r recrded in decibels. The sliding cntrls n the right allw yu t adjust playback r recrding levels, and beneath them is a tlbar with buttns fr cmmn editing cmmands (left-t-right: cut, cpy, paste, trim, silence, red, und, zm in, zm ut, and fit selectin / prject t windw). Intrductin t Audacity Yu can imprt audi tracks frm sund files by selecting File -> Imprt Audi and using the standard pen dialg bx.
Audacity can read the fllwing audi file frmats: WAV, AIFF, AU, MP3, and Ogg Vrbis. Yu will mst likely encunter WAV and MP3 files. AIFF and AU are uncmpressed audi frmats (like WAV) usually fund n UNIX wrkstatins r Macintshes; Ogg Vrbis is a cmpressed audi frmat, like MP3, based n a ryaltyfree, pen-surce algrithm (unlike MP3).! Nte: Imprting audi files will take sme time, depending n hw large they are, and Audacity prvides a prgress bar shwing this. Imprting an audi file creates a new track, which can be seen belw. It s imprtant t remember the distinctin between files and tracks. One Audacity prject can cntain many tracks, which can be used t build up cmplicated audi prgrams. The track displays a wavefrm f the audi file. The x-axis represents time (in the screensht abve, in secnds zming in will give yu finer granularity) while the y- axis represents the amplitude f the audi wavefrm. The amplitude scale is relative, frm 0 t 1, with 1 representing the pint at which the audi will clip (becme distrted). Cntrls t the left f the wavefrm in the track windw display the name f the track (which yu can change) and the audi frmat (in this case stere, 44.1 khz sample rate, 32-bit). In additin, yu can mute r sl the track, which is useful when dealing with multiple tracks, and yu can adjust the track s playback vlume and balance.
Let s take anther lk at the available editing tls: The Selectin Tl wrks mre-r-less like the selectin tl in a wrd prcessr: with it, yu select parts f the audi file t manipulate. The Envelpe Tl allws yu t draw an envelpe n the audi track t cntrl the vlume f varius parts f the track (fr mre n this tl, see the Using the Envelpe Tl sectin). The Draw Tl allws yu t manipulate audi samples when sufficiently zmed in. The Time-Shift Tl allws yu t mve selectins alng the x-axis (time). The multi-tl allws yu t select and draw an envelpe at the same time. Once yu ve selected a sectin f the audi track (pictured belw), yu can cut, cpy, and paste it, just like in a wrd prcessr, either t a different psitin in the same audi track r int a new audi track. Available editing cmmands are fund in the Editing menu, and a number f included effects are available under the Effects menu. Adding a New Track Let s add anther track: G t File --> Imprt, and chse the music track yu dwnladed fr class tday. Yu shuld nw see tw tracks displayed.
Editing Tracks Nw let s shift the snnet track dwn a bit. Select the time shift tl t mve the track dwn a few secnds n the time line. The split tl will allw yu t break a track int tw separate pieces. Let s split the snnet arund the 24 secnd mark (lk at the wavefrm t see where the speaker pauses). Mve yur cursr t that pint, and then g t Edit --> Clip Bundaries ---> Split. Yur snnet track is nw in tw pieces; mve the secnd piece ver a few secnds using the time shift tl. We can use the envelpe tl t cntrl the vlume f the music track. Select the tl, then use it t adjust the vlume f the music track s that it gets quieter while the snnet track plays.
Nw, let s cut the end f the music track and make it fade ut a bit. Use the selectin tl t highlight the last few minutes f the sng, leaving a bit f audi after the snnet track. T make the music fade, select the remaining audi at the end, then g t the tlbar ptin Effect --> Fade Out. Saving and Exprting Finally, Audacity makes a distinctin between Audi Prjects and Audi Files. Saving yur wrk thrugh the File->Save menu will save an Audacity prject (.aup) file. This will keep all yur tracks and edits intact and will allw yu t cntinue wrking where yu left ff. Hwever, fr yur prject t be playable in a standard media player (such as Windws Media Player, itunes, etc.), yu will need t Exprt yur prject instead. There are several ptins fr this in the File menu. WAV files are uncmpressed but are playable almst universally. MP3 files are much smaller, but require the LAME MP3 cdec t be installed in a lcatin knwn t Audacity. If the Exprt as MP3 menu ptin cmplains abut LAME nt being installed, fllw the directins t install LAME and try again.