Bass and Treble

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Bass and Treble increases or decreases the lower frequencies and higher frequencies of your audio independently. It behaves just like the bass, treble and volume controls on a domestic stereo system.
Accessed by: Effect > Bass and Treble...
BassTreble.png

Bass (dB)

The amount of gain (amplification above 0 dB or attenuation below 0 dB) to bass (low) frequencies. Set this to a positive amount to boost the bass, or to a negative amount to reduce the bass. Bass gain is applied to frequencies lower than 1000 Hz, with the most gain being applied to frequencies about 100 Hz or lower.

Treble (dB)

The amount of gain (amplification above 0 dB or attenuation below 0 dB) to treble (high) frequencies. Set this to a positive amount to boost the treble, or to a negative amount to reduce the treble. Treble gain is applied to frequencies higher than 1000 Hz, with the most gain being applied to frequencies above 10000 Hz.

Level (dB)

If enabled by checking the CheckboxChecked.png Enable level control checkbox (see below), this sets the final level or "volume" of the processed audio.

  • Applying a boost to the bass or treble will tend to increase the overall level, especially when boosting the bass. As a result, the final level may be pushed so high that it distorts (clips). Therefore the level control has a maximum of 0 dB (as loud as the audio can be without clipping). If a value above 0 dB is entered, a warning displays to right of the enabling checkbox and the OK button grays out. To allow for less capable speakers or headphones, the level defaults to -1 dB.
  • Reducing the bass or treble may make the final level too quiet.

This control therefore allows the final level to be reduced or increased so that it ends up at the requested level even if adjusting the bass and treble would have resulted in a different level.

  • When adjusting the Level, you can press Preview to hear how loud or quiet the resulting audio will sound.
  • When audio sounds "tinny" or "nasal", this may be because the middle frequencies are too high. To counteract an excess of middle frequencies, try increasing both bass and treble and reducing the gain a little.

Enable level control

When checked (default), activates the "Level (dB)" control above. If this box is unchecked, the Level (dB) control is grayed out and its level setting will be ignored. If this box is unchecked and the Bass (dB) and Treble (dB) settings are on zero (no gain to be applied), "No change to apply." is displayed to right of the checkbox and the OK button is grayed out.

Technical details

Bass and Treble is a two-band Equalizer.

  • The Bass control is a low-shelf filter with the half gain frequency at 250 Hz.
  • The Treble control is a high-shelf filter with the half gain frequency at 4000 Hz.
  • All controls have a gain range of +/- 15 dB.
The half gain frequency is the frequency at which the gain is half of the filter gain. For example, if the filter gain was +10 dB then the half gain frequency would be the frequency at which the gain is +5 dB. However for shelf filters the half gain frequency is typically a fixed frequency regardless of the amount of gain. For other types of filter it is more common to define the cutoff frequency as the frequency at which the gain is -3 dB.

The buttons

Clicking on the command buttons give the following results:

  • Manage gives a dropdown menu enabling you to manage presets for the tool and to see some detail about the tool. For details see Manage presets.
  • Preview plays a short preview of what the audio would sound like if the effect is applied with the current settings, without making actual changes to the audio. The length of preview is determined by your setting in Edit > Preferences > Playback, the default setting is 6 seconds.
  • OK applies the effect to the selected audio with the current effect settings.
  • Cancel aborts the effect and leaves the audio unchanged.

Links

|< Index of Effects, Generators and Analyzers

|< Effect Menu

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