AB9IL.net: Backing Track Preparation Guide

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There are plenty of talented musicians and vocalists in the world who perform without a full live band. For example, Blackjack conducted numerous performances in Macau with one guitarist and a sound technician and no other performers. Its heavy metal guitar was augmented with bass and drum backing tracks stored on a laptop computer. Backing tracks can enhance a performance if they are properly processed beforehand.

The objective of backing track processing is to make all of the tracks consistent in audio qualities, thereby setting up a known and precicely crafted experience for the performer and audience. The steps below accomplish that quite well. Be sure to keep the original unedited tracks in a safe place, and save the working versions once editing is completed. New edits should always begin with originals and be saved as new working versions. Lossless audio file formats are best, but working versions may be saved as mp3 to save storage space. Avoid re-using mp3 files, as the editing and saving process degrades audio quality, and they can sound bad after just 2 or 3 generations.

Step By Step Backing Track Processing:

Note: Most audio workstations can do a batch job on multiple files. Steps 1, 3, 4, and 7 generally are enough for most backing tracks if you automate the process.

  1. Normalize the track. Some soundcards distort when peak levels approach zero dB, so set normalization to -6 dB.
  2. Listen on good earphones and use an equalizer if necessary to correct for too much bass, midrange, treble, etc. Try the "visual EQ" and finesse for good sound.
  3. Apply some amplitude compression, at least 2 to 1. The objective is to make the tracks uniform volume wise, and improve the audibility in loud venues (bars, taverns, amphitheaters, etc). Compression brings up quieter parts and reduces peaks in a split second time frame. Consider using the following parameters:
Attack time:   5 to 30 milliseconds
Release time:   200 to 300 milliseconds
Compression ratio:   2:1  to 3:1
Threshold:   -20 dB
Make-up gain:   +5 dB

Attack time should be set as fast as possible, and release time in the 200 to 300 millisecond range, to handle individual drum beats or syllables of speech. Most of the pertinent parts of a track are louder than -20 dB, so the threshold should be set no lower, to exclude background noise from the process.

  1. Normalize again to -6 dB.
  2. Listen and check for defects of any kind. The peaks should be around -6dB, while the average level (in between the peaks) should be about -9 dB to -11 dB.
  3. If the average level is too low, consider using a limiter. Apply enough input gain to make the average level stay between -9 dB to -11 dB, and set the limiter to act on peaks reaching -6 dB.
  4. Save the sound file if it is within the parameters and sounds good in earphones.
Backing racks raw, then as heard during live performances by Blackjack. (click to listen):
Van Halen:
Ain't Talkin' 'Bout Love

MP3 Backing Track

Processed Backing Track

Live Performance by BLACKJACK

A sound check should be completed prior to each show. First, the live performer should play or sing short parts of the performance at full volume while the sound technician verifies the audio is at the desired level, free of distortion, and properly equalized. Next, the backing tracks should be transmitted and set to a level about 3 dB to 5 dB below the live performer. Verify sound quality and correct any deficiencies. Finally, the performer should do a few snippets accompanied by the backing tracks.

Always avoid overdriving any parts of the sound system! From the mixer inputs to the power amplifier, everything should be linear. The only distortion should be sound effects applied by the artist to his / her instruments.

Following the method given above should result in a high quality sound limited only by the creativity and skill of the live performers. Good luck out there, and remember to keep it loud and clear!

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