Connect the digital audio interface to your computer using a FireWire or USB cable. Although most interfaces take advantage of the fast transfer speeds of FireWire, a number of devices still utilize USB technology.
Connect your microphone to the interface using an XLR cable. Select the interface as your targeted audio input device within your digital audio workstation's (DAW) "I/O settings" menu. This configuration lets you record captured audio from the microphone directly into your computer.
Use the software-based keyboard assignments for pitch and dynamic control within your DAW to input synthesized sounds without the need for a MIDI input device. Software such as Reason, Logic and Record include a mapping for your computer's keyboard in which letter names are translated as pitch values and the numerical keys as dynamic and octave controls.
Press "record" within your DAW and use your keyboard to record the sounds into the software. Think of your keyboard as a MIDI controller or traditional instrument. Pressing the keys will record sounds with the rhythm and pitch you choose.