Re: Help ID slow flasher

From: skywise (
Date: Fri Jul 08 2005 - 17:16:16 EDT

  • Next message: Robert Holdsworth: "Re: Astro E-2 launch" wrote:
    > Do you run your recording PC under DOS or Windows?
    > Generally, Windows can't be trusted to react to keyclicks and other events, 
    > but obviously sound recording must run without any glitch.
    > What program and methods do you use to read the timings from the recording?
    I'm running Windows 2000. Software for recording is Adobe Audition 1.5.
    I'm an amateur musician so I am very adept at digital audio editing,
    often working down to the sample level.
    To find the timings I zoomed into the waveform to the point of seeing
    individual samples and placed cue marks where the snap sounds appear
    to start. Then I just took the time interval between successive cue
    After the timing session I took a time reading from my watch for
    reference and after having gone done something else for a while
    did the same again. After 45 minutes my time error was .299 seconds.
    I chalked this error up to me simply not clicking out those timing
    marks accurately. I'm sure the sound card is accurately timed.
    I knew this whole method would be crude but I felt it would only be
    accurate to about 1/4 sec mostly due to my reaction time of seeing
    the flash and snapping my fingers. Since I knew the approximate timing
    of the flashes I would count seconds in my head and as the time
    approached I'd ready my fingers and stop blinking.
    By your analysis I was apparently much more accurate than I thought.
    Also, I went back and looked at my recording to see about this one
    timing mark that is .8 seconds early, thinking the timing mark may
    have been misplaced. Sure enough it is. It is off about .765 seconds.
    The 6th timing mark of 9.818 seconds should in fact be 10.583 seconds.
    The 7th timing mark of 53.704 seconds is now adjusted to 52.939 seconds.
    No other timings are affected by this change.
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