DC Offset - removing DC Offset in the file

A DC Offset is an offset in the baseline, or zero mark of the waveform. 
A sample wave not centered on the zero baseline in the Waveform Display is 
said to have a DC Offset. This is usually caused by a calibration problem in 
the audio hardware. It is desirable to remove this offset after recording 
because undesirable pops can occur when editing a file with a large DC offset.

To remove DC offset, select the entire file by double-clicking on the wave
display or select Edit Menu ? Select All. Choose Effects menu > Remove 
DC Offset or click the DC Offset button and the selected data is adjusted 
so the DC Offset is aligned to the digital zero point. 


To Reverse a section of the waveform:
-------------------------------------
  * To make a section of the sound play backwards, select the range you want
    to reverse and choose Effects menu > Reverse or click the Reverse button.
    Click Play to hear the selected range play backwards.


To Create Echo Effects:
-----------------------
  1. Select the range where you want to apply an echo effect.
  2. Click the Echo button or select Effects menu ? Echo. A dialog box opens.
  3. Using the sliders, select the Speed and Length of the echo.


NOTE: 
Sometimes when adding echo to a song portion that has already been normalized,
or is at or near its peak level, the sound may 'clip', or distort. When this 
happens, hit the Undo button. If you wish to still add echo, you will first 
have to adjust the volume of the file so that it is lower. Then experiment 
with different amounts of echo until you find the right balance. 

_____________________________________________________________________________