When I am converting messages to the Intervoice ADPCM format, what filtering or optimization is necessary for the telephony network?
Refer to the appropriate Sound Forge or Vox Studio documentation for the post-processing steps for converting a .wav file to InterSoft .ivc file format. The most critical step for voice clarity is equalization. By using the parametric equalization function in the batch conversion tool, you can change the low frequency cutoff of the recorded voice and significantly change the clarity of the voice over the phone. Most customers find that they can achieve their voice quality requirements by modifying the low-shelf frequency of the paragraphic EQ step. Usually they raise the low-shelf to between 200 and 300 MHz for improved clarity. You may find that a modification of the high-shelf parameter also will improve some types of voices. Optionally, you can boost a small portion of the audio spectrum centered at 800 Hz a few decibels to get extra voice clarity. Do not attempt to improve the voice by boosting the bass. While this may seem improved on a hi-fi speaker, the voice quality does not wo
