Chapter 1 Review, Continued (Day 29)

DIXI-ROYD

First Verse:

Domain, what's that? It's what you start with.

Input function? It's what you put in.

x-values, plug it in for x.

Independent, choose 'em all again.

Chorus:

DIXI! ROYD! (repeat four times)

Second Verse:

Range, what's that? It's what you end with.

Output function? It's what you get out.

y-values, f of x is y.

Dependent, that's what it's about.

(to Chorus)

The mnemonics in this song come from Sarah Carter (DIXI-ROYD).

This is the fourth song that I'm writing in 10EDL, our main scale for September and October. The next few 10EDL songs will be written in ABAB format, with verses and a chorus.

At this point, I've found a new strategy for adding guitar chords to my 10EDL songs. First, I use the TI calculator to create two measures/bars in the 10EDL scale. Then I add a sequence of chords (often referred to as a riff) that sounds good with the two bars. Then this riff is repeated throughout the verse.

Then I have the TI create another two-bar sequence for the chorus. As it turns out, the TI chose a pair of whole notes for the chorus -- Degree 7 (F#) and Degree 5 (high C). So far, I've been using a D (or D7) chord for the F# note, followed by our tonic C major chord. Notice that in the standard scale, F#-C is a dissonant tritone, though in true 10EDL this becomes a 7/5 interval -- a better-sounding tritone. The riff for the verses, meanwhile, is Am-D7.

Here's a link to the Mocha code for the song:

https://www.haplessgenius.com/mocha/

10 N=8

20 FOR V=1 TO 2

30 FOR X=1 TO 44

40 READ A,T

50 SOUND 261-N*A,T

60 NEXT X

70 RESTORE

80 NEXT V

90 END

100 DATA 6,6,7,6,10,2,10,2,7,2,8,2,8,4,9,4,10,4

110 DATA 6,6,7,6,10,2,10,2,7,2,8,2,8,4,9,4,10,4

120 DATA 6,6,7,6,10,2,10,2,7,2,8,2,8,4,9,4,10,4

130 DATA 6,6,7,6,10,2,10,2,7,2,8,2,8,4,9,4,10,4

140 DATA 7,16,5,16

150 DATA 7,16,5,16

160 DATA 7,16,5,16

170 DATA 7,16,5,16

Don't forget to click Sound before you RUN the program.

The tricky part was coding these riffs in Mocha. While a single riff can easily be coded using a simple FOR loop with RESTORE, having different riffs for the verse and chorus is trickier -- the only feasible way is to type in each line four times (100-130 for the verse, 140-170 chorus). While the verse contains nine notes in its melody, the chorus contains just two whole notes, so it's not as bad to type in. Later on, more complex refrains will require us to type more (or find some clever way to enter the code).