In the late 1970's I persuaded five colleagues to sing all the parts in Tallis's 40 part motet in an attempt to show what could be done at the time using multitrack recording tape and an early version of Logic Audio (running on a Mac).
The original singers were: Cathy Langdale, Julia Field, Ciaran O'Keefe, Duncan Emerson and Peter Langdale. A few weeks ago I decided it was time to resurrect the project and use newer technology to create a better result.
The first problem was how to get access to the snippets (loads of takes of chunks of each choir recorded separately, but as 5 voices mixed together) as I backed these up on CD using the MAC and the CDs were not readable by PC. I don't use MACs now, but I still had an old iMac with a built-in CD drive, so I was able to access the files, convert them to WAV and then export to my PC. Sadly one small chunk was missing, so I had to recreate this chunk using computer voices. Let me know if you find the bit ! It took quite a lot of time working out which snippet was which within the score and for which choir, but I got there in the end. (I should have named each chunk at the time when exporting them originally to CD, but I didn't have time then).
Using Melodyne I was able to correct some tuning and note errors - not so easy when the snippets were not monophonic. I hope you enjoy this revived performance. It is No.5 in playlist under Choral Works. 'Spem in Alium' is there as a wholly computer generated version too, so do make sure you are listening the right one (by all means listen to both).