With an audio adapter, a PC can record waveform audio. Waveform audio also called sampled or digitized sound utilizes PC as a recording device. Small PC chips built into adapter, known as analog-to-digital converters (ADCs), alter analog sound waves into digital bits that PC can recognize. Similarly, digital-to-analog converters (DACs) convert the recorded sounds to an audible analog format.

Sampling is method of turning original analog sound waves into digital signals that PC can save and replay shown in figure. The system samples the sound by taking pictures of its frequency and amplitude at regular intervals. E.g. at time X the sound might be measured with an amplitude of Y. The higher the sample rate, more correctly the digital sound duplicates its real-life source and larger the amount of disk space required to store it.

Initially, sound cards utilized 8-bit digital sampling that given for only 256 values (28), which could be utilized to alter a sound. Now sound cards have improved the quality of digitized sound by using 16-bit (216) sampling to create 65,536 different values. The highest-quality sound cards feature 24-bit sampling (224), which translates into more than 16.8 million feasible digital values that can be matched to a given sound.

You can test with effects of different sampling rates by recording sound with Windows Sound Recorder or a third-party application set to CD-quality sound. Save sound and play it back at that highest-quality setting. Then alter the file to a lower-quality setting, and save sound file again with a different name. Play back the different versions, and decide lowest quality you can use without serious degradation to sound quality.