Record audio as midi, though convert should work also.

@Lawrence-Bodien Audio and MIDI are some fundamental different things. Audio describes an amplitude of energy which vibrates the air and is registered by your ear as a sound. MIDI is used to send and receive events that trigger digital music instruments and equipment.

So you want to play some notes, lets say on your piano or guitar, and then get the MIDI notes of these tones? You need a different software for this. You can Google for "convert wav to midi" to get some websites that convert your WAV file into MIDI. Or you can buy softwares like Melodyne or AnthemScore. Be aware that the quality of MIDI to audio conversion depends largely on your audio material. Polyphonic audio, where multiple notes are played a the same time, gives mostly inferior results to monophonic audio, where just one note is played at any time. Recorded piano sounds work often much better than other instruments.

I may have lost the scores to a number of pieces that I would like to rewrite with different software. I was hoping to use the midi score to give me an idea as to instrumentation of the audio material. Will this work, or is there a better way?

@Lawrence-Bodien I think the least time consuming way is to get someone on fiverr.com to transcribe your music to a MIDI file from scratch.

For example, loading a complete song in Melodyne (which does gives the best results of many tools I tested) looks like this. This is a piano piece (Martin Tingvall - Hope) and gives some very useful visible information on how to redo the track. But the exported MIDI sounds not very good. But it should be moderately laborious to recreate it from scratch.

This is another example, this time a rock music piece (Led Zeppelin - Kashmir). And the notes are all over the place because drums, vocals, guitars, bass, strings are all on the same track. Yes, you can see some sort of harmonic structure but this would be very tedious and complicated to do.