User`s manual

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3.3: TRAINING CD RECORDINGS
The PCAP II Plus Training CD supplied with the PCAP II Plus is a useful training tool. Each of its 13
noise sample recordings is accompanied by a several suggested setup files (“.dac” files), installed on
your computer along with the other software by the installation procedure.
Table 3.1 summarizes the contents of the training CD. The SETUP column contains the name of the
setup files installed on the disk as part of the software installation procedure (Section 2.2: ). To access
a setup file, click on File in the Master Control menu bar (or press <Alt-F>). Next, click on Open
Setup File (or press <Alt-O>). The available setup files should then appear in the Setup Files box;
setup files have the extension “.dac”. If the needed setup file is not displayed hen attempting to open a
setup file, the path information may require changing. Refer to Section 4.10.2: for additional details.
According to Table 3.1, the first setup file “Training CD Track 3 Solution A.dac” is the suggested
setup file for Track 3 (voice plus swept tones). In all cases the name of the proper setup file for a
particular training track is Training CD Track X Solution Y.dac, where X is the track number and Y is
the solution letter. Usually solutions “A” are the most simple solution, providing basic noise removal.
Solution “B” is the more advanced noise solutions involving several filters to further improve the
intelligibility of the speech. For more information about each solution file, view the Description from
within the Open Setup File window as each file is selected. You may also use the Edit File
Description option from within the File Menu.
The majority of tracks on the Training CD are real world examples chosen to demonstrate both the
processing power of the PCAP II Plus as well as to show how difficult some noise problems can be.
The intelligibility of a few of the more difficult tracks may be very low, even after enhancement.
Remember, too, that the goal of forensic audio enhancement is intelligibility, not audio “quality”. The
aim is to understand what is said, not to make the tracks sound like they were recorded in a studio
environment.
All recordings except Track 13 are monophonic, i.e., the left and right channels have the same audio.
The 13th recording is a Reference Canceller filtering example and has the primary microphone audio
on the left channel and the TV reference audio on the right channel. Make sure to have the reference
audio (right channel) slightly louder than the primary microphone audio for best results.
Playback the CD on a standard CD player connecting its Left and Right Line Outputs to the PCAP II
Plus LEFT and RIGHT ANALOG MAIN INPUTS, respectively. As each track is played, open the
suggested setup file. Try varying individual control parameters to observe overall processing effects.
Have fun!