Record web radio, get rid of crackling noises and remove long silences
Record sounds playing on your PC
Free audio-editing program Audacity (www.audacityteam.org) is great for editing digital files from your music collection as well as voice recordings. But it can also record any audio playing on your computer – for example, an internet radio station, a YouTube video or an iTunes song.
To start recording, open Audacity, select Windows WASAPI in the Audio Host dropdown menu and click the record button. Once you’ve made your recording, click the stop button. If you’d like to listen to your recorded audio on an MP3 player or smartphone you should convert the audio file to MP3 (see next tip).
Save audio files as MP3s
Due to licensing restrictions, the default audio format for files you export from Audacity isn’t the standard MP3 format. This is annoying if you want to play the file on an MP3 player or smartphone. However, there is a way to add MP3 support to Audacity.
First, download the LAME MP3 encoder from www.snipca.com/21615. The file you need will be called ‘Lame v3.99.3 for Windows.exe’ (or similar). Double-click the file and install LAME. Now close and reopen Audacity, then open any Audacity file you want to convert to MP3. Click File, Export Audio, type a file name and choose MP3 Files from the ‘Save as type’ dropdown menu, then click Save.
Remove constant crackling
To reduce the crackling noise when you convert vinyl, open the recording in Audacity and select (using the Selection Tool) a section of the audio that only contains crackling – the first few seconds (before the music kicks in) should be ideal. Click Effect, Noise Reduction, then Get Noise Profile. Now press Ctrl+A to highlight the entire recording and click Effect, then Noise Reduction again. Click Preview and a sample of music will be played with the new effect applied. If you’re happy with how it sounds, click OK to apply the same effect across the entire recording.
You can also try moving the ‘Noise reduction’ and Sensitivity sliders to further improve the recording (simply click Preview when you finish moving the sliders to hear the results). Once you’re happy with the results, export the recording as an MP3 file (see previous tip).
Compress all silence in one go
When you record something live, such as a meeting or perhaps your choir group’s latest recital, you may end up with a recording that’s full of long silences. To remove these, press Ctrl+A to highlight the entire audio file, select Effect, then click Truncate Silence. Leave the Level set to -20dB (decibels) and Duration to 0.5 seconds to let Audacity detect any periods of silence that are half a second long (or more).
Next, choose either Truncate Detected Silence or Compress Excess Silence in the dropdown menu. The former reduces all periods of silence to half a second (or whatever value you specified in the ‘Truncate to’ box) and the latter compresses periods of silence by 50 per cent (or whatever value you entered in the ‘Compress to’ box). Click OK when you’ve done this.
Remove pops and clicks from your file
Pops and clicks can be caused by scratches on your CDs or records. To reduce their impact, click Effect, then ‘Click Removal’. When the Click Removal tool opens, click Preview to listen to a sample of the recording with the current Threshold and Max Spike Width settings applied. If your recording sounds better, click OK to apply the settings to the entire file.
If you can still hear pops and clicks, decrease the Threshold setting by 20 and increase the Max Spike Width by 5. Click Preview again and repeat as necessary. Just be aware that moving the Threshold close to 0 will eventually distort the audio. If this happens increase the Threshold value until the distortion disappears.