I find the new tone to the doxology before the "Great Amen" to be extremely frustrating.
I don't have the exact notes in front of me, but the previous tone ended something like, "doh-re-re-mi-re-do-do" on the words, "forever and ever," indicating a clear "do-do-re" for the congregation to sing "A-me-en." In fact, after singing that for a few months in a particular church, it's almost impossible to not sing it whenever I heard that tone at another church, but found myself being interrupted by the instruments proclaiming the beginning of a completely musically unrelated "Amen."
Now, it is quite interesting (and wonderful!) how the priests are being encouraged to sing so many of the newly translated parts of the Mass, and they are! And, many churches, at least among those I'm familiar with, are taking a stab at singing the corresponding parts, including the "Great Amen." But unfortunately, whatever musical genius decided to CHANGE the final ending tone of the doxology, along with the words, has provided a disappointing level of confusion for anyone trying to sing a simple "Amen" here.
The new doxology ends something like, "mi-mi-re-do-re-mi-re," on the words "forever and ever," (sorry if that's not exactly right, I've only heard it a few times,) but I've even checked the Roman Missal, and yes, the congregation is expected to start their "Amen" on DOH when the priest has just finished on "RE!!!!" ARRRRRRGHGHGHHGGHGHGHG!!!!!!!!!!
(I'll start it strongly on the proper note, doh, and the congregation cautiously joins in, as it is slightly intuitive, especially if the congregation is able to follow someone who knows what they are doing.) But... I am extremely sad as I suspect that this hesitancy of non-naturalness of being expected to start on a different note than what has just been heard, will not contribute to any congregations ever finding this tone "natural," which is what I found when I sang it previously.
It seems that hardly anybody is truly satisfied with the new translation, or at least the baggage that it brings with it (I heard a good priest recently complaining over the word "prevenient" in one of the prayers for the Immaculate Conception. And while I can't really argue against his complaint that he had no idea what it meant, I do wish that at that moment I had said, "Well, even if we don't know what it means, it does make me want to go and look it up!" le sigh.)
Anyhow, an interesting unintended consequence of how the priests have not been encouraged at all to sing their parts for the past 40 years, is that now, once they are, I have heard more than one person comment on how it helps the congregation with the new translation. By this I mean, in many churches, the automatic response to a spoken "The Lord be with you," is, of course, "And also with you." BUT... if "The Lord be with you" is sung, then it suddenly requires a moment of thought for the congregation, and they are more likely to sing "And with your spirit," especially if they are in a church which hasn't been singing the dialogues for the past 40 years.
So...for once, we can thank them for trying to (indirectly?) eliminate certain degrees of solemnity from the liturgy! It has helped at least one thing about this new translation to be easier!