Audio Level Adjustment

 

Adjusting the playback volume of songs to create a coherent listening experience of audio content in the Montreux Jazz Festival digital archive.

 

 

The audio level and loudness of the Montreux Jazz Festival recordings can dramatically change from one concert to another. This is because the recording techniques and equipment used to capture concerts varied greatly over the years.

To resolve this problem, a student at EPFL developed a tool in accordance with recommendations from the ITU (International Telecommunication Union) and European Broadcasting Union (EBU) which maintains perceived volume of songs in the Montreux Jazz Festival archive at a constant level throughout a person’s listening experience. This tool solves the problem of volume fluctuations during song transitions.

 

Characteristics of Audio Level Adjustement tool :

  • The algorithm runs on a PC.
  • It does not affect the archive recording, but calculates correction factors (level offset, compression etc.) data which is stored in the MJF database and applied during playback.
  • The correction takes into account actual loudness as perceived by human ears and not just on electrical peaks and average energy.
  • Dynamic range compression is avoided.

 

 

EPFL Partner

LCAV (Audiovisual Communications)