          6/8 And Other Time Signatures

MMA does have a few problems. A biggie is how it deals with compound
time signatures.

MMA really expects to have quarter notes as the denominator in a time signature.
So, times like 3/4, 4/4 and even 5/4 work just fine (assuming that someone has
written an appropriate groove!). However, when it encounters signatures with an
8 (or 16 or 32) as the denominator things get tricky. For writers of groove
files I'll try to give a few pointers.

It is important to remember that time signatures are NOT fractions!
6/8 and 3/4 are NOT the same. This is music, NOT math. But, MMA is a
dumb computer program and based on math, not music. So, how should this be
handled?

OPTION 1
--------

Well, says the groove writer: Since a song in 6/8 time is probably a march
or jig-like song AND you know from your musical education that 6/8 time is
a duple time which is counted in 2 (NOT 6!) using a TIME value of 2 makes
sense. You can do this quite easily with the following sequence of commands:

    Time 2
    TimeSig  6/8

Now, when you set up sequences and chord lines you need to remember that
you only have 2 beats and 2 tab stops. So, for a sequence you can have:

    Chord  Sequence  {1 4 90; 2 4 90}

Which plays a chord on beats 1 and 2. Now, when you enter chord lines you
do:

    1   Am   Bm
    2   C    G

and it all works. Writing solo lines becomes a bit more complicated: we
only have 2 beats, which are really quarter notes. So ... if we have a
nice little line of 6 eight notes on a piece of sheet music we need
to translate this to 2 sets of eight note triplets. Using the built in
command option for Solo/Melody tracks you can also use STRETCH.

OPTION 2
--------

Another option is to write the groove in 3/4 time. Mathematically this will
work, but it may create more problems than you expect. So, we start off
with:

    Time 3 Tabs=1,2.5
    TimeSig  6/8

Note that here we have used the TABS= option which will help in keeping
chord lines sane. But, for defining a sequence we have to do something
like: 

    Chord  Sequence  {1 4 90; 2.5 4 90}

And those fractional offsets will be a bit of a nightmare. This is
not a recommended method. But, in your songs you can nicely do:

    1  Am Bm
    2  G  F

And it'll all work. Even Solo/Melody lines work on a one-to-one setting
from the sheet music.

OPTION 3
--------

The final method, and probably the best one, is to "pretend" that
the song is written using 1/4 notes (not 1/8th):

    Time 6 Tabs=1,4
    Timesig 6/8

    Chord Sequence {1 4 90;  4 4 90}

And, again, our song file is:
 
    1  Am Bm
    2  G  F

For chords which are not on 1 or 2 (which is actually 4) you can use
the handy @ notation. So, to play chords on beats 1,2,3,4,5,6:

    1 Am Bm@2 C@3 D@4 F7@5 G@6
    
The only problem with this is that since MMA thinks we have 6 1/4 notes
you will need to change the note duration for a Solo by doubling the
duration of each note (1/8ths become 1/4, 1/2 becomes 1, etc.) Using
the Solo option "Stretch" is very handy in this case.

RECOMMENDATION
--------------

It's really up to you, the song, the style of of the groove and song. If
you look at the supplied grooves you'll see that more use a TIME of 6, some
a TIME of 2 and one with TIME 4.

Isn't MMA nice to give you all those options!

Have fun.

bvdp, April 2020.

