MIDIRenderer is a MIDI rendering software that allows you to convert
MIDI to WAV, MP3, OGG, FLAC, APE, AMR or WMA files. It is often used when
you need to playback MIDI composition on the portable player, car audio
system or burn MIDI files on Audio CD.
Unlike the other similar programs MIDIRenderer provides direct MIDI rendering to waveform without using sound card and allows you to use any high-quality instrument sound instead of Windows General MIDI set.
Well, you will avoid background noise from sound card, you not need high priced sound card for high quality output and conversion will be much more faster than real-time recording.
Because MIDI (Musical Instrument Digital Interface) file contains no music. It records how music is played, containing "events" which control when each note of each instrument starts, finishes, how loud, what note of the scale, etc. MIDIRenderer use high-quality synthesizer with SoundFont support which convert MIDI sequences to waveform.