Preprocessing signal before LPC I have a signal that contains the speaking of three vowels. The signal is contaminated with dc offset and an interference at 60 Hz. I want to perform LPC for the synthesis of the spoken vowels. Do I have to remove the dc offset and the interference before performing LPC?

My initial signal looks like this:

 



There is also another question of mine about LPC here https://stackoverflow.com/questions/28909899/weird-output-of-lpc-algorithm
Usually before processing the speech signals, they are passed through a high pass filter with cutoff frequency of around 150 Hz to remove such artefacts.