Here are links to the URLs - the Website addresses - for the various Works we'll be singing this term. Click on them, and you'll be taken to the relevant page of the main Website, from which you can access/download the desired Midi files for the individual Pieces.
J S Bach's Magnificat in D.
The Website pages contain links to Midi files for all the parts (Soloists included). You can listen to them either using a Midi Player, such as "MidiPlay" (see below), or instead using Choral Music Tutor ("CMT"), which is a web app that plays Midi files. Choral Music Tutor runs on any device - any Desktop PC (Windows or Mac), Tablet (Android or iPad) or Smartphone (Android or iPhone) - that can browse the internet. It is not an app that you have to download or install.