It says the timpani part was accommodated to fit the music. But given the translation of the dies irae. I think the dissonances make the piece much better. Even if they may or may not exactly fit the root or 5th of whatever chord.

Wouldn´t name it an improvisation, but glad you like it.

I don´t think it changes the character, and I do think that it´s indeed a question of instrument limitation. You can read my blog clicking on the link provided in the description, where you can see why I edited the part in the way I did.

If the timpani dissonances make the piece much better, why doesn´t the oficleide play the same part? It would make the Dies Irae even better... ;-) My opinions on this issue are in my blog. There´s a link to it in the video description. Please visit it and read my little essay (it´s divided into three parts).

Who says the oficleide has to play the same part? It's like the same reason the tuba doesn't mimick a timpani part in a fanfare. It has it's own unique special part to play. And odds are since the dissonance IS there the low brass instruments probably contribute to that. So like say the timpani rolls an E, and low brass plays A and an E on top of the A. While trumpets 3,2&1 play B,C, and E. well if that low A in the brass isn't there then The chord quality completely changes.

Have you read my blog? I have explained my points there (extensively). Honestly, don´t wan´t to start it all over again. I played this modified timpani part, I was happy, the conductor was happy... Who could ask for anything more? You may like it or not, but I have a solid point in what I´m doing. If I was playing under you, you would tell me not to edit the part, and I would be more than happy. I was playing this under an open minded conductor, and I was more than happy. I did music. Problems?