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C!T ROM 2
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ctrom_ii_b.zip
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ctrom_ii_b
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FLIGHTSI
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TEKSTEN
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ENGSND
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ENGSND.TXT
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1992-10-31
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8KB
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160 lines
ENGINE SOUNDS FOR FS4/SGA
Tim Vasquez, 71611,2267
OK, folks, face it. No one really gives much thought to it, but sound
does represent a completely different dimension of reality. Many programs
and games for the IBM offer dazzling graphics, but sound always seems to
take a back seat. Why let that happen when you're running one of the best
simulations ever made for the PC?
Flight Simulator 4 (by Microsoft) and the Sound and Graphics
Adapter (by Mallard Software) give you real, true-to-life aircraft noises.
Instead of artificially producing them, they access real digitized (sampled)
noises to produce the sound. And with the diversity of people that own
FS4 and SGA, there's certainly room for improvement, almost like the
sceneries created by hundreds of FS4/ASD (Advanced Scenery Designer) owners.
For example, I realized that I had sounds from a Boeing 747 cockpit
on one of my tapes here at home. And it hit me that I could put this in
FS4. I ran into problems, though, just when I thought I was all done.
The problem is that FS4 loops jet and prop sounds (plays them over
and over and over until you exit the program). If you simply hand any
digitized sound to FS4, the program won't find the loop markers, and this
will cause bad sound and temporary memory problems and lockups. And even
if you do get a readable file into FS4, it's got to sound just right.
Here's the solution......
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RECORDING THE SOUND
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Getting a high-quality sound into your computer is obviously the main
objective. After all, if you're going to hear the sound for hours on end,
it had better sound good!
Unfortunately, my Sound Blaster card does not have direct-wiring inputs.
(Creative Labs was great servicing me under warranty, but I'll always
gripe and moan about the way they designed the card without phono inputs!!)
I've asked in IBMNEW and MIDIFORUM about a way to direct-wire into the mike
jack, but no one seems to have a solution.
So, my "high-tech" approach is to play the original sound loudly through
a set of high-quality headphones. I plug a good condenser microphone into
the Sound Blaster and cup it with my hand into the headphone ear. This does
a surprisingly good job at getting the right amount of treble and bass into
the sample. Volume is important -- if you play the original too softly, the
sample will be weak and scratchy, and if you blast the original, your
sample will sound distorted. Experiment!
Moving along, use a sampling program such as SFXBlast, Blaster Master,
or other such high-quality programs. Many of them can be found on
CompuServe. Once you're set up, it's important to use a sample rate of
about 5.7 kHz. The samples supplied with SGA use a speed of about 5740 Hz.
I haven't really experimented with higher quality sounds (greater than
10 kHz or so), since they do take up more space and run shorter, but if you
manage to get FS4 to swallow them, more power to you.
Sounds are stored in .VOC files. This is a standard sample format for
digital samples, and the filenames normally end with -- of course -- .VOC.
Always use this format for your FS4/SGA endeavors.
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EDITING THE SOUND
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Now, you must loop the sound end-to-end. You will mainly be struggling
against file size. At a sample rate of 5.7 kHz, a 10K file will give you
about two seconds, long enough for a decent sample. If you go any shorter,
your noise will sound a lot more artificial. Any longer (say past 20K),
and you create more headaches for FS4, which only has a certain amount of
memory to deal with.
Editing and trimming the best portions of the sample are important.
After all, when you hear a 1-2 second snip once, it might sound great. But
play it over and over and over, and you'll quickly pick up distractions,
such as volume wavering, periodic oscillations of engine noise, or
random cockpit sounds.
Here, a good sample editor is your best friend. Again, SFXBlast and
Blaster Master are good choices. You need to start out with a big chunk of
sound (about 50-100K) and use block looping commands to track down the
choicest parts of the file. When you find it, DELETE all other parts of
the file (don't just erase them) -- so that when you run a loop on the
ENTIRE SAMPLE, it should sound close to the way you want it.
Once you do this, you need to "trim" the edge of the file. Zoom in on
the very edge as close as you can and look at the graphical waveform
(the sound trace). You need to make this waveform continuous during the
transition from the end to the beginning of the file. In other words, if
the file begins with the wave at a peak, you need to end the sample with a
similar peak. If it ends on the zero line, trim the beginning so that the
file starts on the zero line, too.
If you don't do this, chances are you'll hear a discernable click every
time the file is repeated. It's impossible to get rid of the click
completely, but by matching up the file end-to-end, you should be able
to keep it under control.
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INSERTING A LOOP COMMAND
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There aren't many programs that will do this for you. Neither
SFXBlast or Blaster Master can do this. Your best bet is to use the
JOINTVOC command supplied with your Sound Blaster. (I have the V1.5
version; I don't know whether the V2.0 or Pro users have this command).
But anyway, it's:
JOINTVOC /T(newfile) /R9999 (oldfile) /RE
For example, if you have a Cessna 172 noise saved in C172.VOC, you
can try this:
JOINTVOC /TC172NEW.VOC /R9999 C172.VOC /RE
This inserts the repeat and repeat end codes in your sample which
FS4 requires. Once you finish this, you can ignore the old file.
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PUTTING IT IN FS4
-----------------
The final step is to place the new file in your Flight Simulator
directory. You should take a look at VOCHLP.TXT, a file available in
CompuServe in the FSFORUM, Library 5. This shows the best way to copy
your sound samples into your directory.
Now for a filename. Go to your FS4 directory and list the *.VOC files.
These are the ones SGA uses. Just replace either the jet or prop file
(whichever is appropriate). However, whenever you go to FS4 menu 1,K
(sound) and select User Defined Sounds, FS4 will access those sounds whose
filenames end with 2. For instance, the program will use JET2.VOC
instead of JET1.VOC. This allows you to keep the original sounds in FS4
if you get tired of your own noises.
But you can cheat by just overwriting the existing .VOC files. It's
not the most popular way of doing it, but I do it (I have my SGA .VOC's
backed up in a subdirectory and on my master disk, of course).
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AFTERTHOUGHTS
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You don't really think about it, but sound does have a major impact
on the reality of the simulation. And if it's the real thing -- look out!
Personally I'd like to see more true-to-life .VOC samples. I'm not
really sure how many people are interested or have the resources. After
all, not all of us have access to a DC-10 cockpit or a F-16 flight, but each
properly edited file is a jewel to bring into FS4. Even those little
things, like the MD-80 landing gear computer voice (available in CompuServe's
FSFORUM), adds a little sparkle to a static desktop simulation.