Impulse recovery mode You can choose from three Impulse recovery mode options to determine the method used to
recover the impulse: Use the start and end of the recorded file as timing spikes, Auto-detect
timing spikes, or Do not use timing spikes. Each of these modes is described below.
• Use the start and end of the recorded file as timing spikes This option specifies that the
beginning and end of the recorded file are used as timing spikes. This option is
recommended for the best results during impulse recovery.
You must trim the file as close to the timing spikes as possible for this method of recovery to
work most effectively. The first sample of the file should contain the start of the first spike
and the last sample of the file should contain the start of the second spike. Therefore, most
of the second spike is deleted.
• Auto-detect timing spikes This option specifies that the timing spikes exist near the start
and end of the recorded file and that they should be auto-detected. Timing spikes are used
to correct for clock or tape speed mismatches. If you have not trimmed the recorded file so
that the timing spikes are at the very beginning and end, select this option for the best
results.
With this option, you need only ensure that the first spike occurs within one second of the
start of the file and that the second spike exists in the file. To improve detection accuracy,
you can also boost the level of the start and end spikes in the recorded file.
Tip:
If the spike’s level is close to the noise floor, select the Use the beginning and end of the
recorded file as timing spikes option.
• Do not use timing spikes This option specifies that no timing spikes are used. This is the
least desirable option as no timing information is used. To use this option, you must trim the
recorded file so that the test tone starts and ends at the start and end of the file, with no
blank audio before or after. This option should only be used if the timing spikes are lost in the
recording or if you are certain that the play and record clocks are synchronized (such as when
using an ADAT).
USING ACOUSTIC MIRROR AND WAVE HAMMER |
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