How do I know when the next note starts in sheet music?

Question

I can't understand the note duration notation very well.

In the image below, the highlighted A in the second measure seems to start half a beat between the first and the second beat. But shouldn't we wait for the bass A two beat duration to finish, and only then hit the second A? How do we know when the second A should start? In this case I know intuitively (knowing how the piece sounds) that it should start half a beat after the bass A. How would we write these notes if we wanted the second A to start only after the bass A finishes its duration?

Answer 1

I can't understand very well note duration notation.

No wonder. The music you're trying to read is objectively incorrect in several ways. I won't list them all, but as you've noticed the vertical alignment is out of order. Furthermore, the rhythmic notation does not comply with the meter. Follow the advice in the comments to get a different copy.

I would use the original edition, which you can find (among several others) at IMSLP. This piece is on page 6 of that edition.

You may prefer a modern edition, but you would be well advised to invest in a professionally edited and engraved one.

Edit: I see that you've indicated in the comments that this is a guitar arrangement. If you click "arrangements and transcriptions" on the IMSLP page, you'll see that there is an arrangement there of this piece for unaccompanied guitar.

Answer 2

The score sheet you quote here is literally garbage. Most likely it is the result of importing a foreign file into a music program that follows different conventions (like exporting MusicXML in one program and reading it with another program that is not prepared for parsing the output of the other program) or trying to combine different voices by program in a manner not supported by the program and then saving the resulting mess instead of trying to figure out what went wrong and fix it.

Or it is the result of an attempted conversion of MIDI into a score sheet that has gone horribly wrong.

Or some music program has nominal export for the input format of a different program, but this functionality was never tested or used with music of the given structure/complexity.

One can speculate a lot about the exact reason, but the result is the same: this is garbage, and so much so that divining the intent has become impossible. You need to try finding a different source. Or, in case this file was given as a file purportedly in a format for your music program, see if the same source does not provide a ready-made PDF file for your use that is less likely to be garbled like this one is.

Answer 3

This writing is really very odd. But you can derive the correct rhythm if you imagine the eighth notes as off beat (counting “and”) ... there’s no logic in the notation of the half notes. Imagine you have a 4 voice part written on 4 different layers and channels. But it will still be difficult to derive a reasonable rhythm. It will be much easier to compare this miswriting with another arrangement like e.g. the following:

Answer 4

I fully agree with all the comments remarking that the typesetting is a complete abomination here, however it does make “sense” in that the note values do express how long each note sounds on the guitar. Essentially, what happened here is that each string has its own voice, and the notes blend into each other. I give it five points for this detail attention... and minus 5000 for jamming this almost completely unnecessary information into the score without making it clear how it works!

What's missing completely are the rests that most of the voices have, if we're going to give a complete one to each string. Here's a “correct” rendition of this idea:

Of course that's even more unreadable than the version you used. And it's completely unnecessary too to be so explicit about the length each string sounds, because it's generally obvious from the harmonic progression. The standard way to express “leave strings ringing” in guitar music is to simply add some slur-ties, use only as many voices as needed, and write those fully with all notes cut to the length and rest-filling needed to make the rhythm clear:

Answer 5

Observe that there are two voices, one with stems up and one with stems down. This is common in classical guitar transcriptions (but poorly done in your version). When reading such a score, remember that the up-stem (treble) voice is independent of the down-stem (bass) voice. So the A in the second measure starts on the first beat of that measure.