[Harp-L] The TWIN-HARMONICA SYSTEM is Announced

[Eugene Ryan <ryan.eugene@xxxxxxxxx>]

I posted this on another forum - I thought it might be useful for people
interested in the possibilities afforded by this system.

================

The enharmonics on the DoubleChrom make for some very interesting
possibilities.  The projections below are for diminished chromatic tuning;
perhaps someone else will figure it out for solo-tuning or other chromatic
tunings.

Unless I've made a mistake, it looks that no matter what way we have the
slides, as long as one goes up a semitone and one a tone, you can play any
note and therefore can play any scale or pattern as all blow and all draw.
One of the problems in shifting between blow and draw is that we lose the
legato of continuing with an all blow or all draw pattern.  Harmonica
tunings with lots of enharmonics (diminished, Brendan's Slide Diatonic, my
Irish Fiddle tuning, others) mitigate that to some degree, but there's
usually some point where you have to change breath direction.

So any phrase on a Diminished DoubleChrom could be all blow or all draw.
Let's test that assertion.  We just have to prove that any note in a dimi
hole or neighbouring hole is available as blow or draw

So if we have a cross section here of the "top harp" if we want to think of
it as being logically on top (it may not be, depending on how we arrange
the tuning and slides):
hole                4  5    6
blow slide in    F   Ab B
blow slide out  E  G   Bb
draw slide out  F# A   C
draw slide in    G  Bb Db

And with a 2nd type of slider going up a tone this gives us the "bottom
harp" :
hole                  4   5   6
blow slide in      G  Bb Db
blow slide out    F#  A C
draw slide out    Ab B  D
draw slide in      A   C  Eb

So let's look at each note in hole 5 to see where it also exists - that's
enough to extrapolate everywhere for the diminished tuning:
G: hole 5 blow slide out (top harp)
G: hole 4 draw slide in  (top harp) - bendable
G: hole 4 blow slide in  (bottom harp selected with whole tone slider, is
the same as F on top harp but shifted up a tone on bottom harp)

Ab: hole 5 blow slide in (top harp)
Ab: hole 4 draw slide out (bottom harp, F# -> Ab) - bendable

A: hole 5 draw slide out (top harp) - bendable
A: hole 5 blow slide in (bottom harp)
A: hole 4 draw slide in (G up a tone) - bendable

I'm also showing the draw slide in note, but that's the same logic as for
the G:
Bb: hole 6 blow slide out (top harp)
Bb: hole 5 draw slide in (top harp) - bendable
Bb: hole 5 blow slide in (bottom harp)


To also think about this, think of where the whole tone or semitone
triplets are currently awkward with the dimi.  That gives a good indication
of where we have to change breath direction and come up with some
compromise, such as getting the note by bending (which I do for those
awkward 16th -note triplets that shift between blow slide in and draw ).
The awkward one for semitone up or down triplets or trills is the blow
slide in to draw on the dimi... for me, that's Ab -> A.  That's available
on the "bottom harp" diagram above in hole 4 draw.  All whole tone trills
or triplets (or just quick moving between them) are available by playing a
note on the top harp and using the whole tone slider to get the other.

I think that Brendan's invention is a very significant move forward in the
harmonica world.

-- 
Eugene