Make a voice sound like it's on a phone line/earplug

Special Interest Groups Audio Processing
1

I’m looking for a decent way to make a voice recording that’s nice and clean sound like:

  1. something you’d hear a caller on a radio call-in show sound like

  2. something that you’d hear on an earbud in a spy movie/action game. “Your objective is the tower: place c4 around the base…”

You know, stuff like that. How do I process audio to make it sound like that?

2

Use Audacity 1.3.x

Find the file “EQCurves.xml” on your computer and open it. (probably best to also make a backup copy in case you mess up).

You will see that the pre-defined Eq settings begin with:

and end with:

Add this as a new entry (add it directly after one of the “” tags)

    <curve name="Telephone">
          <point f="229.889129366427" d="-120.000000000000"/>
          <point f="229.897181759969" d="-0.214285714286"/>
          <point f="2457.729966530459" d="-0.214285714286"/>
          <point f="2457.816054154370" d="-120.000000000000"/>
       </curve>

Save the EQCurves.xml file

Now open Audacity 1.3.x and Import your audio track.
Make sure that the track is selected, and from the Effects menu select “Equalization”

Select the “Telephone” preset and apply it.

3

Done! Sounds great!

Playing around with it a bit, I’ve found you can get a similar, different effect by applying the ‘am radio’ Equalization effect several times to the same sample.

Thanks for the help!

4

I’m not able to find the file EQCurves.xml. Where is it?
there is any other way to do the same job?
regards.
ermete

5

That depends on your operating system.
For Windows it is probably in;
Documents and SettingsApplication DataAudacity

You may need to make hidden files visible to find it.

Yes, you can set the Equalizer manually - turn down all frequencies below 300Hz, and all frequencies above 2500Hz.

Another way is to use a high pass filter set to 300Hz, then use a low pass filter set at 2500Hz.

6

I’ve had some very strange behavior in the Equalization Effect after playing with it for a moment. Whenever I try to implement a new preset, the graphic representation will change to the appropriate EQ but the dropdown list ALWAYS goes back to say ‘custom’. In other words, I can select different presets, but they’re labeled incorrectly by the Equalization menu. This happens whether I’m using an unedited EQCurves.xml file or not.

It’s not a deal breaker, but it is annoying.


EDIT: It’s a new topic, so I’m not sure if it needs it’s own thread, but here goes anyway: For basic voice cleanup, what kind of basic EQ settings to you pros use? I got some decent results by tapering off the very highest and lowest frequencies…

7

First off, the equalisation effect in Audacity 1.3.5 is quite buggy, and the effect in Audacity 1.2.6 is quite limited, so if you still have Audacity 1.3.5 or earlier you should upgrade to Audacity 1.3.6.

In Audacity 1.3.6, each time that the Equalization effect is called, it will open with the settings that were used last. The name (“custom”) in the drop down box is not really relevant, but just indicates that the parameters are adjustable. To save an Equalization setting, you should enter a new name (preferably a unique name to avoid confusion), and save it. That effect can then be recalled by selecting it from the drop down menu, even if it was not the last setting that was used.

Filtering out the very highest and lowest frequencies is often a useful basic “clean up” job. You can also use the high pass and low pass filters to do a similar job (this second method will generally do the job better).