Working with computer-based digital audio requires large amounts of hard disk space. If you are planning on creating new audio files on disk, you'll need enough hard drive space to contain them.
A good rule of thumb is:
Each minute of 16-bit stereo sound at 44.1 kHz requires about 10 Mbytes of disk space.
Thus, with an empty 200 Mbyte hard disk you can record a little less than 20 minutes of CD-quality stereo sound (precisely, 19 minutes, 20 seconds).
Sample Rate values are indicated in Hertz (Hz), or "cycles per second." For professional audio work always use the 44,100 Hz (44.1 kHz) setting, which is the CD-quality sample rate. 22,050 Hz is considered acceptable quality for many interactive multimedia applications. 11,025 Hz is a low-resolution, "voice quality" sample rate. 8000 Hz is becoming a common Internet audio sample rate. Hyperprism-DX supports Wave files at all of these rates, and also offers 48 kHz recording as supported by your audio card and host application.
Using a lower sample rate file will proportionally reduce your disk storage requirements, i.e. a 22 kHz file will only take half the space of the same sound stored at the audio-CD rate of 44.1 kHz. However, using a lower sample rate will reduce the high frequency response of your sounds.
To avoid aliasing (a metallic-sounding type of digital
audio distortion), don't use high-frequency filter settings above about
10,000 Hz when using 22 kHz sample rates, or settings above 5,000 kHz for
11 kHz sounds.
Hyperprism-DX and Ray Gun support 8- and 16-bit audio files. In addition, Hyperprism-DX and Ray Gun plug-ins can process 24-bit files if your host application supports them.
Lower resolution formats reduce storage space requirements. Unfortunately, lower bit depth and sample rate settings can compromise the audio quality of your sound files. Lower sample rates lose high frequency response, and 8-bit storage causes a reduction of your sound's dynamic range, resulting in noisier, "grainy-sounding" audio, especially during softer passages.
If you are creating 8-bit audio (for example, for multimedia or Internet distribution), you will get best results if you do all your signal processing at 16-bits and 44.1 or 48 kHz, and then create an 8-bit file at the end of the process.
The distortion of low-level signals can be minimized by normalizing your 16-bit file before 8-bit conversion, or by using dynamic range compression or manual gain-riding to make soft parts of your sounds louder before reducing their resolution. RayGun.exe users please note that the program makes no provision for bit depth or sample rate conversion; it processes audio and saves it at whatever the original bit depth and sample rate were.
Audio files come in three flavors: Mono (one-channel), interleaved stereo (two channels in a single file) and split-stereo (two channels in two separate files). Most Windows audio programs, offer support for both mono and interleaved stereo .wav files.
Hyperprism-DX and the plug in version of Ray Gun will process any file format supported by your host application; this is typically .wav files, but other formats may crop up.
If you're recording audio for eventual
use on a CD, we recommend that you always create 16-bit stereo .wav files,
sampled at 44,100 Hz. This is the file specification you'll need to create
"Red Book" audio CDs, and is what programs such as Adaptec Easy
CD Creator Deluxe 3.5 accept for burning audio CD-Rs. Sticking with these
settings will prevent file-conversion headaches down the road. Note also
that most digital audio/sequencing programs have native support for "CD-quality"
SDII or .WAV files (according to whether they run under the MacOS or Windows),
and allow you to open them directly so you won't have to chew up additional
hard drive space making format-converted copies.
Many different sound file formats exist, including SDII,
AIFF, .SND, .AU, and others. While we cannot read these files directly,
there are a number of sound file format conversion utilities available.
After conversion to .wav any sound can be used by Hyperprism/Ray Gun, as
long as it has been converted to a compatible sampling rate and bit-resolution.