I'm transcribing a piano ballad by a contemporary-progressive-symphonic-chamber-rock band, and I have come across these two ornaments. Each first measure on the below image shows the passage without ornament, while the second measure shows the ornament transcribed verbatim.
I would like to add ornament notation to each first measure so that it becomes the second. What notation should I use?
How about using acciaccaturas? Sure, you won't get exactly the triplet rhythms, but if you want those exactly you wouldn't use ornaments. This is how it would look:
You could use a pair of acciaccaturas each time with a single (quaver) beam, but the double beam seems more in keeping with the surrounding music to me, and suggests the rapidity with which they need to be played. You don't really need the slur either, but again it suggests that these notes are played rapidly almost as a single gesture.
The usage above is very simple, and would be particularly effective if the music is moving along at a reasonable pace (leaving little room between the semiquavers for anything rhythmically complicated). However, if the tempo is pretty slow, you could stick with your "exact" rhythmic notation, as a player would be more easily able to execute it exactly as you want it, with no ambiguity. If you choose to do this, you simply need to tidy up your beaming, to make it obvious where the beat groupings are:
Also, it occurs to me, that each of these decorative passages could either feel as though the quicker notes are part of the gesture along with the preceding tied note, in which case the following note feels somewhat accented, or as part of a gesture with the following note. Using a slur can help to make this distinction clear, if indeed there is one, so I have shown both types of slurring in the above excerpt.
Finally, @PatMuchmore makes a good suggestion, that the second of the two ornaments could be written as a mordent. By placing the mordent over the second half of the tied note, it should be clear that the upper note and return to the first note should be delayed:
UPDATE: I spent a while trying to find an example of this use of a "delayed" mordent on a tied note (see the comment discussion below), but haven't found one yet. Its rhythmic interpretation looks pretty clear to me, but unless somebody else can point towards an actual example of this usage, it should not be considered standard notation.
OK, first things first, those two ornaments, though similar, aren't exactly the same. The first one is only a single added note (E natural) while the second is two added notes (a new Bb plus a return to the original A).
For a non-Baroque specialist, I think there are only five ornaments that one can assume a musician fluent in classical notation will easily recognize. The trill, the turn, glissando, mordent and "grace note" (which is generally interpreted very differently in Romantic, modern and contemporary music than the same notation was in Baroque and Classical). (the first examples on this wiki: http://en.wikipedia.org/wiki/Musical_ornament) The first three are obviously irrelevant to your examples.
Your first example can only really be expressed as an ornament via grace note (probably slurred into the following D). I'm not sure that this adds a whole lot as opposed to your fully-notated version, but it is at least more visually simple in regards to rhythm.
Your second example could kind of be indicated with a mordent (wiki: http://en.wikipedia.org/wiki/Mordent) above the A in your first version. This indicates a move to the diatonic step above and a return to the original pitch, so it would give you the note content you're looking for. However, I don't think this will sound quite like your fully-notated version indicates you want it. A mordent happens right at the beginning of the ornamented note, but you've notated the added pitches as quick notes leading straight into the upcoming F. Once again, I think grace notes are the better option, two sixteenth grace notes,Bb and A, slurred into the F on the next beat.
If you're worried about people interpreting the notes in a more Baroque or Classical style (on the beat, and taking half the time of the next note), then you can always add a note that all grace notes are to be played quickly before the note they're attached to.
