sound cardA sound card is an embedded system that enables sound in a device or computer. Sound card is an expansion card that is inserted in the expansion slots. A program controls it and outputs the sound to speakers. Depending on expansion slots different standards of sound cards are available.

Evolution Of Sound Cards

In the earliest computers, there was only one sound that was beep. The designers can only play with this beep. They could change the beep's pitch, quality, length, frequency and time to generate music. It was the year 1980 when designers came up with sound card, a card dedicated for one purpose that is to add sound functionality to computers or motherboards.

Sound Card Information Translation

Sound is analogue and computer works on digital data 0s and 1s. What sound card does it translates between real analogue waves and digital data. A sound card uses three components to translate such information. ADC – analogue to digital converter
DAC digital to analogue converter.
Interface for expansion slots (PCI, ISA, etc)
These days codecs are common in sound cards. CODEC chips perform both ABC & DAC functionalities.

ADC

ADC converts the analogue data to digital data through sampling. Sampling is converting the data into 0s and 1s form. Higher the sampling rate higher will be the quality of sound.

DAC

DAC converts back the digital data to analogue data through reverse steps as ADC.

Sound Card Components

Besides the components required for translation a sound card contains some additional components. These components include:

MEMORY

The built-in on card memory allows faster and better data processing and performance.

DSP (Digital Signal Processor)

Digital signal processor allows the card to perform calculation for digital and analogue conversions itself. This not only takes the load off the computer processor but also improves card's performance and processing speed.

Some motherboards do not contain sound cards. Instead they have integrated Digital Signal Processor. DSP can provide 3-D and surround sound. But the designers have proven that integrated DSP cannot match with the quality from a Sound Card.

I / O Connections

• To work with speakers and microphones almost every sound card contains I / O connectors.
• Connections for 3-D and surround sound support.
• MIDI – musical instrumental digital interface connects to a synthesizer.
• USB and FireWire connect the sound card to the digital audio or video.

Sound Card Availability

The sound cards are available in the market as internal and external. Internal cards are inserted in the expansion slots integrated on the motherboards. External are plugged into the USB or FireWire connectors.