Terry Hancock wrote:
> * Given what we're trying to do (see the
> sites below for details), what sort of audio
> capability should we incorporate?
>
> * How should we handle synching animation to
> audio (as for characters talking?).
>
> * What about music (e.g. MIDI) support? Good
If your target systems can spare the CPU usage, Timidity might be a
good choice since it doesn't depend on hardware synths which are 1)
impossible to predict
how they'll sound, and 2) often suck. Also if you include Timidity
in your game, you can bundle the sound samples you want it to use.
> compressed sound formats (is MP3 the right
> choice for us, for example?).
For dialogue and so forth? It should be just fine. Decoding eats
quite a bit of CPU unfortunately.
Another option is Ogg Vorbis (see http://www.ogg.org/ )
which is currently in beta, sounds similar to MP3, and unlike MP3 is
completely open source.
If you want to save CPU usage, and are distributing your games on
CD-ROM, just put uncompressed audio clips on the CD. For dialogue
you could do fine with mono files with a lower sampling rate such as
11.025 kHz which would consume roughly 20 kB storage per second
(versus 166 kB / sec. for CD quality).
> * Studio issues and clean-up. This is a
> volunteer effort, so we can't afford a sound
> studio to work in. What can we do to clean
> up input from home-computer microphones, etc?
Unfortunately not much. "Garbage in, garbage out" is a rule that is
very hard to escape unless you can afford expensive professional
de-noising software (costs thousands, I think). You're better off
getting good sound quality first rather than trying to polish a ...
er... smelly fish.
OK, here's SlinkP's Instant Home Recording Correspondence Course!
For dialogue and sound clips you should (roughly in order of
priority):
* Use the best microphone you can afford. Do NOT EVER use one of
those things that comes with a cheap soundcard. They suck, suck,
suck. If you don't know anything about microphones, you can't go far
wrong by going to Ebay and buying a used Shure SM-58 or SM-57 for
$50.00. (They're $100-ish new.) These are virtually indestructible,
versatile, and sound pretty decent. If you can afford $300 get a CAD
Equitek E-300 or maybe a used Sennheiser MD-421. That's a big step
up in quality. Beyond that, the sky's the limit. You may want a
couple of mics if you're recording a lot of dialogue - it helps if
performers each have their own mic.
* Put a pop filter (foam blobby) on the mic to avoid those big
booming "P" sounds. An excellent makeshift filter that actually
sounds better than foam can be made by stretching panty-hose over a
wire coathanger bent into a 6" circle. Put this between your voice
talent and the microphone. Tape it to your mic stand with duct tape.
Congratulations, you're now a home studio recordist. :)
* Use a decent soundcard. You can get something adequate for your
purposes quite cheaply. See my Audio-Quality-HOWTO at:
http://www.linuxdj.com/audio/quality
* Record in the quietest room you can find. Computer fan and drive
noise is a problem and it's very hard to get rid of it once you've
recorded it.
When I can't get away from the computer, I've had decent results
getting as far from the computer as I can go in the room, point the
mic away from the computer, and find a way to prop up a heavy sofa
cushion between the mic and the computer (maybe a foot from the
mic).
* Get your voice talent to hold reasonably still. You don't want
them leaning in on the mic and backing away from it by accident -
the sound will be very uneven. (If they have experience with
microphones, let them do what they want... they can actually use mic
distance to their advantage!).
* Minimize room acoustics. Rooms with carpeting and lots of soft
surfaces (sofa, bed, pillows, laundry...) will help reduce the
effect of room acoustics which are often more noticeable on the
recording than they are on the room, and often don't match the sound
of the environment you're trying to create. If your character is
speaking in a cathedral but it sounds like they're in your living
room, it'll be very unconvincing. Try to record "dry" sound (as
little ambience as you can manage) and add reverb later to suggest
the right space. (No reverb for outdoors, big reverb for
cathedral-type spaces, a little short reverb for small indoor
spaces, distinct echoes for a mountain ravine, etc...). You can also
make the sound more "dry" by getting the performer very close to the
microphone (but see the next note). Remember, it's easy to add
ambience, and almost impossible to take it away once you have it.
* Place the mic carefully. Putting the mic farther away from the
performer will help to negate the effect of them moving around by
accident, and gives you a more "natural" vocal sound, but it will
increase the amount of background noise and room acoustics you pick
up. Conversely, putting the performer right up on the mic reduces
background noise and room acoustics, but the sound can get
artificially "boomy" sounding and it's very sensitive to the
performer moving even a couple inches closer or farther away. This
is something you learn with experimentation and experience.
* If you can possibly afford it, use an external preamp. Plug the
mic into the preamp, and plug the preamp's output into your
soundcard's line in. This will get you cleaner sound than going into
a soundcard "mic" input (ranges from tolerable to terrible).
Probably the best value is to buy a secondhand Mackie 1202 mixer
which gets you 4 high-quality preamps for $200-ish, and then you
have a mixer too.
* Put your mic stand on a board on top of a piece of stiff foam.
This cuts down on the boomy clunking noises when your voice talent
moves around.
* Experiment experiment experiment.
* Lurk in alt.music.4-track (amateurs) and rec.audio.pro (the big
boys) and absorb information from them. Deja.com is your friend.
Don't post in rec.audio.pro unless you really know what you're
talking about.
--
................. paul winkler ..................
slinkP arts: music, sound, illustration, design, etc.
web page: http://www.slinkp.com
A member of ARMS: http://www.reacharms.com
