The process that an A/D converter uses to capture an analog signal is called sampling. Sampling is like taking a snapshot of the sound wave. This creates a stepped representation of the electrical signal. When computers digitize sound, the computer takes snapshots of the sound at fixed points. A digitized version of the above wave might look something like this:
While the shape is similar to the analog wave, they are not exactly the same. The more often that the computer takes those pictures of the sound, the closer to the original it will sound. The number of times per second that a computer takes that snapshot is refereed to as the "Sampling Rate ". The higher the sampling rate, the more samples taken per second. There are many different common sampling rates that you might see:
44.1 kHz = 44,100 Samples per second - This is the standard for CD's
48 kHz
88.2 kHz
96 kHz
Bit Depth
The other aspect of how computers digitize the audio is the "resolution" or "bit rate"..The resolution of a sample represents its dynamic range, or levels of volume. The higher the resolution, the greater the dynamic range; and the lower the resolution, the less the dynamic range. For example, a 1-bit system can only represent two levels of volume - off or on (0 or 1). A 2-bit system can represent four levels of volume - off, soft, medium or loud (00, 01, 10, 11). A typical resolution is 16-bit, which is the resolution used for Audio CDs. A 16-bit resolution can represent 65,536 (or 96 dB) levels of dynamic range. A 32-bit system can represent 1,048,576 (or 192 dB) levels of dynamic range. That is over one million levels of dynamic range!
http://208.39.189.27/classroom/audio/an ... igital.cfm
Just a little something to show the diffrence between the to, a 24 bit sample will make anything sound a louder because of the snapshots of the sound takin. Even if your sampling from a 16bit sound to 24bit.