Thread: Soundcard FAQ
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Old 9th December, 2002, 04:16 PM
Aedan Aedan is offline
Chief Systems Administrator
Join Date: September 2001
Location: Europe
Posts: 13,075

Misc Questions

What is the diference between Analog and Digital systems?
Digital systems work with discrete finite numbers. Analog systems work with continously varying signals. Converting between the two is never completely accurate.

What is sample rate?
The sample rate is the frequency with which the analog signal is examined and converted into a number. The more often the signal is examined, the closer we can get to tracking how quickly it changes. The sample rate is expressed in kilohertz, or thousands of samples per second. However, the highest frequency that can be digitised is half that of the sample rate!

Why is the number of bits important?
Each bit that is used in a sample contributes to the overall accuracy of the sound. With only 1 bit, there are only two levels we can generate - sound and no sound. With 2 bits, we can generate 4 levels of sound. With 3 bits, we can generate 8 levels of sound. At 16bits, we can generate 65536 levels. At 20bits, we can generate 1048576 different levels!

What is Environmental Audio?
Environmental Audio is a technique for making a sound fit the environment it is supposedly occuring in. Imagine a sound like water dripping into a puddle. If you were inside a house, it would make one sort of dripping noise. If you were in a cave, it would make a different noise. Environmental Audio provides all the cues for the setting of the sound.

What is EAX?
EAX is a Creative Labs standard for Environmental Audio. EAX can apply effects like reverb and filtering in order to make the sound more realistic for the environment it is supposedly occuring in. For gaming, this makes the sound far more realistic than playing a standard sound.

What is DirectSound?
DirectSound is a part of Microsoft's DirectX. It provides methods for getting sound to a soundcard quickly, and also provides some environmental audio features[/b]
Any views, thoughts and opinions are entirely my own. They don't necessarily represent those of my employer (BlackBerry).