Both SandvichParty and Dimondium are frequent contributors to Everypony Sings, and we're quite fond of them. So when they team up and collaborate on an original song, it's all the better!
Their collaboration is called Heart of Knowledge, and it's a great tribute to Twilight Sparkle. I really like the melody and the way the trumpet and strings work together. Give it a listen!
You can find both SandvichParty and Dimondium on Youtube.