Voice inversion with unisons in standard/tab staves
I report here, because I'm not very sure of myself as to whether this is a bug or not? The appearance made me think yes - in this case -, but maybe I did not consider the totality of the issue?
So:
1) New score with standard staff + linked tab staff
2) Entry four times four sixteenth notes. Like this.
3) Change Voice1 -> Voice II
4) Entry four quarter notes on the four bass A (unisons)
Result expected (particular on the tab staff)
Actual result:
To get the result I want, this one:
I have to select the number 0 (which has switched in voice 2), note by note, or by "More" -> "Same voice, same staff", then Ctrl + Down Arrow .
This is easily done, of course, but the initial (actual) result is not it surprising? Thanks.
| Attachment | Size |
|---|---|
| 1voice1.jpg | 35.42 KB |
| 2voice 2, expected result.jpg | 33.73 KB |
| 3voice2, actual result.jpg | 32.85 KB |
| 4 file.jpg | 27.83 KB |
Comments
I want to clarify that this behavior is not new at all. I have always encountered it with the Nightlies (thus, since several months).
I adapted, until I've been wanting to ask the question!?
That chord would be impossible to play with any normal hand anyway.
Normally one would allow the voice 2 A to ring and it should be indicated by an endless slur in the tab attached to the open string.
In reply to That chord would be by ChurchOrganist
Michael, I'm not sure we understand each other;)
Of course, I know (I am graduate guitar teacher!) that the two A on strings 6 and 5 (on the tab staff) are impossible to play. That is for this reason I hide the number 5.
But at the same time, I absolutly obtain what I want on the standard staff. Because I want to point that the A bass notes (quarter notes) form the melodic line. So I have to distinguish two different voices, and thus with the stems in opposite directions.
In reply to Michael, I'm not sure we by cadiz1
Ah I get it :)
So this is a limitation in the tab that could really use some addressing.
My workaround would be to add the crotchet A's to the TAB instead of the notation using the 5 key in voice 2
Not tried this btw but in theory it should work :)
In reply to That chord would be by ChurchOrganist
As it is an arpeggio it isn't impossible to play. And how you would play it depends on the musical intent. If you want the low A to sustain, i.e. as voice 2, it would make sense to play it as an open string. If you don't then you either damp the open string or play the whole thing at the fifth fret, where it is easier to damp the notes by lifting the fingers.
But the top E is also going to sustain if played open, unless the player damps it deliberately.
Maybe I am misunderstanding something (the expected result does not look different from actual?), but I do not think I would consider the actual behavior here to be a bug. There are two different notes that need to be played here. Both happen to have the same pitch, but if you didn't *mean* two different notes, why *write* two different notes? The algorithm figuring out the tab is trying to give you what it thinks you want - two different notes that happen to have the same pitch. You can't do that with only one string, so it uses two. Seems to be doing exactly what you asked. If you really wanted only one "A", you shouldn't have written two, but instead used a rest in voice 1. Then it would have worked as you expected. As it is, though, if you write two notes in the standard staff as you did,. there are going to have to be two notes in the tab staff as well.
In reply to I do not think I would by Marc Sabatella
It's a feature of guitar notation Marc.
There are conventions in it which go against normal engraving rules.
Bear in mind that once played a guitar note will remain until it dies away, and much of the conventions have developed to show where the melodic line is and where the accompaniment is, so the performer is able to interpret the piece correctly.
In reply to It's a feature of guitar by ChurchOrganist
To get to the essential, my question is:
Why the first A in Voice 1 (blue), located on the second line of TAB staff, like this.
![1file.jpg]( "1file.jpg")
So - when I continue to enter notes via the standard staff-, why this first A is replaced, on the same string and same Tab staff line, by the quarter note A of the Voice 2 (green)?
![2 File.jpg]( "2 File.jpg")
I hope be clear?
In reply to To get to the essential, my by cadiz1
Much clearer to me.
In reply to To get to the essential, my by cadiz1
Dup.
In reply to To get to the essential, my by cadiz1
Hmm. I can't really see the different colors clearly in the screen shot. But I think maybe I do understand. Is it the following:
1) enter sixteenths into standard staff as shown in voice 1
2) note that on the tab staff, the first note appears as fret 0 on 5th string
3) now switch to voice 2 (still in note input mode, still on standard staff)
4) enter quarter note A
Result: the note in voice 1 that was previous fret 0 string 5 moves to fret 5 string 6 in order to make room for the new note
In other words, the complaint isn't that both notes appear on the tab - that much we all accept is correct. The problem is that given the order in which you entered the notes, you expected the two notes switched: the voice 1 note to remain on fret 0 string 5, the voice 2 note to be on fret 5 string 6?
Had you entered the notes in the opposite order, it seems you would have gotten the desired arrangement.
Apparently, the rule seems to be, newly entered notes get entered at the "best" position, and any existing notes get pushed onto lower strings. Or something like that.
Am I understanding better now? I guess I still am not sure exactly why this is a problem - again, it seems a case of MuseScore not being able to read minds, but this time, it's about which of the two notes you wanted on which string. You can always switch them with ctrl+up/down. Again, unless I'm still missing something.
In reply to It's a feature of guitar by ChurchOrganist
I get that it's a common convention; I don't get why MuseScore would be expected to read someone's mind and know that this was desired in this case. After all, in other cases where you actually *do* want a double stop (same note played one two different strings), MuseScore is expected to figure *that* out automatically. I don't see how it could possible know which situations are which. So the workaround of hiding one tab fret seems perfectly justified to me.
Unless I'm still misunderstanding something, which is entirely possible. Could someone please explain step by step exactly what you are pressing and in what order, and at at what precise point something happens that you feel is not correct? I have been assuming the problem is that you are entering the quarter note in voice 2 after already entering voice 1, and at the moment you add the note in voice 2, you are *not* expecting it to show up on the tab staff, whereas I *am* expecting it. Am I completely misunderstanding?
EDIT: see above. I guess maybe I do understand after all. The complain isn't that there are two notes. The complaint is that given the order in which the notes were entered, he expected the strings to be reversed. Right?
In reply to I get that it's a common by Marc Sabatella
There will always be specific valid requests. My hope is that 2.0 will be released soon so that I can take some time to examine it.
Regards,
In reply to I get that it's a common by Marc Sabatella
There will always be specific valid requests. My hope is that 2.0 will be released soon so that I can take some time to examine it.
Regards,
In reply to I get that it's a common by Marc Sabatella
I do not know if I can be more clear (:
1) Standard staff + tab linked staff
![1result.jpg]( "1result.jpg")
2) Voice 1: A E A C arpeggio (16th)
3) Then, Add in Voice 2 one A, the same (unison), but quarter note
Expected result.
I expect this result because the four notes 16th in voice 1 (blue) are already written, and I expect that the second A (voice 2) comes on the alternative location, ie on the tab first line (number 5)
In guitar: this note (A) may be made on the fifth open string (O number), or on the fifth fret of the sixth string (number 5).
@xavierjazz: Note that I have never made, at no point in this post, a specific request. It is only a question concerning the distribution and display of two notes (equal in a standard staff) but can located differently on the lines of a guitar tab staff.
Me too, I am looking forward to use 2.0 :)
In reply to I do not know if I can be by cadiz1
Yes, thank you, I do understand now. You expect the first "A" you enter to "win"; that other notes you enter in other voices should need to be placed on other strings, rather than "stealing" the string already given to the first "A". This does seem reasonable.
In reply to Yes, thank you, I do by Marc Sabatella
Yes again, it is exactly that, word for word! :)
I tried your idea to start with the Voice 2. I had never thought of that, because it seems less "logical" or "natural" to start with voice 2, and continue through the voice 1 (in the most common cases). But it works!
And so, I can immediately select the numbers 5 and make them invisible.
I will continue my experimentation with this idea. Thanks again.
In reply to Yes again, it is exactly by cadiz1
I agree, not necessarily logical to start with voice 2. Remember, the other workaround is to use Ctrl+Up/Down to reverse the two strings after entering the notes.
Me, I'm just amazed any of this work at all :-)
In reply to I agree, not necessarily by Marc Sabatella
:)
In reply to I agree, not necessarily by Marc Sabatella
Of course, I had always used Ctrl + Up/Down. No choice, I thought (:
But we understood each other.
It is not "logical" that a note, or a number, "steals" the place of another note or number input before it.
@Cadiz... I see why you are concerned about the voicing of the A note in the tablature - you want an easier way to make all the fifth fret A notes invisible.
Also, after reading ChurchOrganist's comment about guitar notation vs. conventional engraving rules, I revisited some of Carcassi's guitar pieces and they are rife with notation like this (similar to yours):
NOT FOUND: 1
Apparently it is the very nature of stringed instruments' ability to play the same note at different fingerboard locations which give rise to this situation where MuseScore actually shows the two enharmonic tones in the tablature - with the resultant 'impossible' fingerings.
Of course, as Marc mentioned, a rest can be used in voice 1 - although this would eliminate the double stem.
Also, I tried ChurchOrganist's suggestion to use the tab staff for note entry of the crotchet A, but the 5 key enters a '5' in the tablature, not a crotchet.
You'll probably have to keep using 'invisible' for the time being to hide those enharmonic notes.
Regards.
In reply to Yikes!...Tablature by Jm6stringer
@Marc: "In other words, the complaint isn't that both notes appear on the tab - that much we all accept is correct. The problem is that given the order in which you entered the notes, you expected the two notes switched: the voice 1 note to remain on fret 0 string 5, the voice 2 note to be on fret 5 string 6?
Reply: Exactly!
In reply to Yikes!...Tablature by Jm6stringer
Doesn't mean the Carcassi pieces have been notated well. Probably notated by someone who doesn't understand that guitar music tends to be the art of the possible rather than the art of what you want.
(I am a guitarist!)
It seems to me we have to clearly distinguish between two areas:
1) Differences between 'standard' and tab notation (leading, among other, to the "impossible tabs")
2) Fretting algorithm
1) Difference between notations
Let's take Jm6stringer example above: to me the TAB is a rather accurate rendition of the contents of the standard staff. The fact that the resulting fretting is beyond the possibilities of a standard human hand is a rather clear indication that the original standard notation as written is beyond human possibilities.
As ChurchOrganist pointed out, this is because the standard notation in the top staff is not to be taken 'literally' (as a pianist would execute it, for instance), but follows different conventions, a specific 'guitar dialect', so to speak.
I don't think MuseScore could be expected to know all the different 'notation dialects' for all the instruments. If the required contents of the standard staff is different from the required contents of the TAB staff, there is no alternative to use two not linked staves and fill each one as needed.
I think this area could be tagged as "Won't fix" because 'fixing' it (assuming it is possible) would raise more problems than it would solve.
2) Fretting algorithm
This is a more complex area. Keep in mind that the algorithm, which assigns string and fret to a note which does not have them yet, should accommodate a variety of situations: entering a chord from top to bottom note, entering a chord from bottom to top note, possibly split across several voices, and so on.
Each time a note is added, deleted or changed in pitch, the algorithm evaluates all the notes, across all voices, and attempts to assign string and fret to each. It does some assumptions; for instance, it assumes that, if a note already has fretting, it should be kept, unless it conflicts with another note (no two notes on the same string) or it leaves some notes without a legal fretting; in which case, it starts over afresh.
The bottleneck is: when some notes have fretting (previously entered notes) and some do not, how (better, when) to consider the notes without? Before, after, drawing straws?
The current implementation evaluates not-yet-fretted notes rather early, as this seemed to work better while fretting chords both entered from top to bottom and from bottom to top. This explains why, in the OP initial example, the last entered note (the A crochets) seem to 'steal' the 5th string from the A semiquavers: the former (being not fretted yet) is evaluated earlier and 'reserve' the string most suitable to itself (the 5th); the latter come later and have to be content with the remaining 6th string.
It can be improved, of course, but correcting the specific aspect described in this thread (which I would label as 'advanced') should not interfere with the basic working.
In no case, the algorithm can be expected to take into account more than the current chord or to be able to 'plan ahead' the appropriate fretting for a whole passage.
So, unless there are other, more basic, bugs, my first reaction for this second area is "Postponed". With the following workarounds:
*) If the automatic fretting is unsuitable / unexpected, try entering the TAB first: there you can decide the fretting yourself in each detail.
*) If this leads to unidiomatic standard notation, then the two notation are not compatible (area 1) above) and a general purpose notation programme like MuseScore cannot be expected to 'translate' one into the other: use non-linked staves and fill each with the specific details of each convention.
Thanks,
Maurizio