Re: engraving rules question - voices with merged heads

[Janek Warchoł]

W dniu 29 stycznia 2011 12:00:50 UTC+1 użytkownik James Bailey
<address@hidden> napisał:
>
> On Jan 29, 2011, at 11:25 AM, Janek Warchoł wrote:
>
>> 2011/1/29 James Bailey <address@hidden>:
>>>
>>> On Jan 29, 2011, at 12:17 AM, Janek Warchoł wrote:
>>>
>>>> Hi,
>>>>
>>>> recently i was told that this notation
>>>>
>>>>  { \mergeDifferentlyHeadedOn << b'2 \\ { b'8 a' g' f' } >> }
>>>>
>>>> is not allowed in vocal music (i.e., the noteheads shouldn't be
>>>> merged). Is that true?
>>>
>>> correct. you shouldn't merge heads in vocal music.
>>
>> Interesting. Is that true also when both voices have filled noteheads,
>> i.e.
>>
>>  { << { b'4 g' } \\ { b'8 a' g' f' } >> }
>>
>> ?
>> Here LilyPond merges noteheads automatically, and i don't remember any
>> simple means to switch that off.
>>
>> Thanks,
>> Janek
>
> This is different. One voice has a beam, while the other doesn't. There
> isn't any way to mistake a half note for a quarter note in this case, as is
> the case in the other.

Sorry, but it doesn't make sense to me. In both examples one voice has
a beam and the other doesn't.
Please look at the attachments:
A - everything is clear. notes in upper voice must be quarters because
they have filled heads and no beams, while notes in lower voice must
be eights because they have filled heads and beams. Here we agree.
B - note in upper voice must be a half because it has a hollow
notehead and no beam. First note in lower voice has a hollow notehead,
but it cannot be a half because it has a beam. Therefore, it must be
an eight note. I don't see any way in which a half note could be
mistaken for a quarter note in this example.
The only case in which a half note could be mistaken for a quarter
note would be in C. I agree that merging heads in C would be totally
unacceptable.

thanks,
Janek

C.png
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A.png
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B.png
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