[Audacity] Radio Voice Effect

Tutorials

[Audacity] Radio Voice Effect

dklon
Wednesday, June 19, 2013 - 03:30

Trying to get that lo-fi effect for your voices or sounds? Audacity can do it right out of the box.

What You Will Need

  • Audacity. It's free and easy to use.
  • Plugins - You won't need any extra plugins for this effect.
  • eSpeak (optional) - If you don't have a microphone or don't feel comfortable with your voice, you can use this for text-to-speech synthesis. The output isn't amazing, but it can suffice and is unencumbered by any licensing restrictions.

Creating the Effect

  1. Take a recording of your voice in Audacity. You can load any WAV output from eSpeak in as well.
  2. Select all of the sound by using the selection tool or press Ctrl-A.
  3. Select Effect -> High Pass Filter... from the menu. When prompted, you can use the default Cutoff frequency (usually 1009 or 1015 Hz).
  4. Select Effect -> Amplify... from the menu. Generally 11dB is a good value. Make sure "Allow Clipping" is turned on; we want to get the maximum amount of grunge we can.
  5. Repeat Step 3 and 4. When running Amplify again, set it to about half the dB value of the original (around 5-6 dB if you set it to 11 the first time).

Adding Static

Want something even grungier? Add some static!

  1. Add another blank track (Project -> New Stereo Track, or Mono Track if you prefer).
  2. With the blank track selected, click Generate -> White Noise from the menu. Set the duration to the same length as your original recording.
  3. Notice that the white noise generated is quite loud by default and can overpower your original track. Lower the gain (on the left side of the track) to at least -12 dB. This should put it in the background and let the primary sound take the forefront.
  4. Click Effect -> High Pass Filter... from the menu on your noise track. Repeat this several times. This will help homogenize it so it sounds like both sounds are coming from the same source.
  5. [OPTIONAL] - If you want to make it sound more spacey, add the Phaser effect to both tracks. This effect is also included with the base install of Audacity.

You can also cut just a small portion (0.25 seconds or even shorter) of the static track and put it at the beginning and end of every line of voice dialogue. This gives the effect of a radio transmitter signal cutting on and off.

Have fun!

qubodup
joined 15 years 7 months ago
Wednesday, June 19, 2013 - 08:44
qubodup's picture

Thanks for sharing.

I also created a radio voice tutroial: youtu.be/86P3whnojag

You must be using an older Audacity version or perhaps you left out paramters (for example the amplitude of white noise generator or the High Pass Filter rolloff parameter).

Audacity 2.0.3 won't let me press "OK" when amplifying to 11dB. I can press return to force it but I'm not sure it uses the provided parameter.

Exact parameters, especially for the phaser effect would be nice.

A sound comparison: freesound.org/people/qubodup/sounds/192004/

A video of me applying the effect: youtu.be/zX092syuXiI

dklon
joined 12 years 6 months ago
Wednesday, June 19, 2013 - 17:11

You're right qubodup. I'm using version 1.2.6 on the computer I used to make the tutorial. I have 2.0.3 installed on one of my other machines and I will look at the differences.

Using just the defaults for the Phaser effect will produce a space-y enough effect. Just so we're on the same track though, here is what I have for Phaser:

  • Stages: 2
  • Dry/Wet: 128
  • LFO Frequency (Hz): 0.4
  • LFO Start Phase (deg.): 0
  • Depth: 100
  • Feedback (%): 0

I listened your comparison sound, and it came out very close to my results. If you want it to be even more AM-radio sounding, repeating Steps 3 and 4 will further distort it.

Originally I was going to write up something on using the FFT Filter but I thought that might be too complicated to show bandpassing without getting into a lot of hand waving. It's more exact and quicker but it can be harder for someone starting out.

 

dklon
joined 12 years 6 months ago
Wednesday, June 19, 2013 - 17:19

I looked at 2.0.1 on the other machine, and was able to create the same effect.

For the High Pass Filter in Audacity 2.x:

  • Rolloff (dB per octave): 12 dB
  • Cutoff frequency (Hz): 1000.0

For Amplify, here are the settings:

  • Amplification (dB): 11.0
  • Allow clipping: Checked

Setting the Amplification will automatically set the New Peak Amplitude, which you don't need to touch.

If you have the Multiband EQ VST plugin, you can take your final output and run it through that also, setting everything on the low bands and the high bands to -70.0. Try it with the first two on the low frequencies (50 Hz and 100 Hz) and last two on the high frequencies (10000Hz, 20000Hz). This will crunch it even further if you want.

copyc4t
joined 11 years 7 months ago
Thursday, June 20, 2013 - 09:14
copyc4t's picture

In Vega Strike a similar, all-Audacity approach was used to get that effect. It was initially meant as the translator voice for incoming alien communications, but it sounded good for general radio and we used it for almost all the factions.

Quoting from  http://wiki.vega-strike.org/Development:Audio#Voice_Acting

  • edit out unwanted noises like lip smacking, breathing, etc

  • apply noise removal and click removal effects
  • apply a low pass filter for 15K Hz, other values default
  • apply a high pass filter for 1000 Hz, others default
  • apply the leveller (heaviest setting)
  • if desired, adjust pitch
  • if desired, repeat the click removal, filters, and leveller again
  • make other edits as required
  • amplify to full volume

The suggested addition of static can of course be applied here too like the icing on the cake :)