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A comment on The THX Sound.

Re:The THX Sound by sneak on Sunday May 27, 2012 @11:55AM (#4030295)
Macintosh boot chime ROM routine:

http://www.folklore.org/projects/Macintosh/more/BootBeep.txt

And the story:

http://www.folklore.org/StoryView.py?project=Macintosh&s...

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Re:The THX Sound by bemmu on Sunday May 27, 2012 @11:58PM (#4031861)
Impressed that this short bit of assembler code was responsible for the chime I hear when I start up my Macbook Pro, I set out to convert it to Javascript. Well, a few hours into this project when I start hearing the first (still quite off) results did I learn that actually the current chime is very very different from the original Mac chime: http://www.youtube.com/watch?v=GSuVacw8I-o

What I don't quite get is that the asm code seems to start with a sharp square wave that smoothens off as time passes, but in that video the first sound already sounds very smooth in the beginning.

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Re:The THX Sound by Someone on Monday May 28, 2012 @07:34AM (#4032904)
Read http://www.mactech.com/articles/develop/issue_16/034-038_Qui..., especially the part that says:

   "Square wave sounds. Unknown to most, the square wave synthesizer never produced
    true square waves. It was more like a modified sine wave. This has been corrected.
    As a result you'll notice that the Simple Beep sounds different. It can now be
    heard as it was originally designed to sound."
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