Do I need Phantom Power on my audio interface?

Phantom Power allows your condenser microphone to operate. Some other devices such as active DI boxes will use Phantom Power. If you're not using equipment which requires Phantom Power then it's not a feature you will find necessary, however virtually all USB audio interfaces come with Phantom Power functionality as a feature.

Do all interfaces run on USB bus power?

No. While there are some small audio interfaces which will run via bus power, interfaces with more inputs or other specific features will require a power supply to function.

What is a USB audio interface?

A USB audio interface is an external device that allows you to bring audio and MIDI in and out of your computer in real time.

Are USB audio interfaces any good?

Yes, a huge amount of music created over the last 20 years has been created using a USB audio interface.

Is there an audio interface with USB input?

While there have been a select few M-Audio audio interfaces that have featured USB inputs that allow you to treat the audio interface like a USB hub. It's far more common to see digital ADAT and optical inputs on audio interfaces to expand your inputs.