Will a sound card help the quality of audio recordings?

Some people also seem to use external devices too for podcasting and the like. What are they for? Just some kind of equalizer?

Solution 1:

TL;DR: If you're serious about broadcasting, yes, they will help!

Here's the main problem: The sound "cards" included in motherboards of typical PCs or laptops are of rather bad quality. Here are some drawbacks:

• They might lack shielding, thus picking up interferences from the surrounding hardware
• You can't connect a professional microphone to them. Simple computer microphones are not professional. In no way they are.
• They might introduce latency when recording (sometimes, even 20ms is a lot). When you want to "overdub" (i.e. record over) your own recordings, this is frustrating.

With external audio interfaces (that's the common term), you overcome all that:

• They are shielded and away from the computer, sometimes with a separate power adapter.
• You can connect professional, high quality microphones to them, using XLR.
• Even a microphone for $80 like the classic Shure SM58 will get you a dramatic improvement in sound quality.
• There's virtually no latency involved in recording at all.

External audio interfaces are mostly connected through Firewire (IEEE 1394) or USB 2.0. They come in price ranges from around $100 up to thousands of dollars, due to differences in the quality of the microphone preamplifiers, the number of inputs, routing capabilities, etc. For simple podcasting, a simple audio interface will also do.

Here's an example of a very basic external audio interface:

You can see that there are two microphone XLR connectors, as well as a headphone connector. The knobs allow you to change the microphone gain as well as the headphone volume.

Some manufacturers offer audio interfaces bundled with microphones, which seems like a good deal for podcasting.