MathStep - a double stepper arppegiator

[bantri]

An attempt to create arppegios based on a scale and using two steppers with 3 basic inputs each (I increment, N total cycle and M point to reverse cycle)

---

MathStep2005-bantri.pch2
Description:		Download
Filename:	MathStep2005-bantri.pch2
Filesize:	2.9 KB
Downloaded:	1341 Time(s)

---

[mosc]

To me at least, this is abolutely facinating. I love the melodies this thing comes up with. It beats randomness cold. Have you explored these kind of arppegiators before, perhaps with a programming language or something?

I will have to stare at this for a long time before I grasp this, but it's well worth it.

[bantri]

[bantri]

[bantri]

[quote="bantri"]

[mosc]

What does the "bounce" do?

[bantri]

the bounce function starts counting from at the same time as totcycle and defines at which point the increment changes signal, if bounce is greater than totcycle then the sequence never enters backward stepping.
On the other hand it is advisable to also set the bounce to be equal or greater than totcycle/2 because if the stepper starts from 0 and bounces before halfway then it will go past zero on its way back into negative values.
example
inc=3
totcycle=8
bounce=5
VBounce on the 5th element (inverting increment)
1 2 3 4 5 6 7 8 9 10
0 3 6 9 12 9 6 3 0 3
^after 8 counts load initial state

[mosc]

So, do I understand correctly, bounce is a change in direction after a certain number of steps?

[bantri]

[blue hell]

lovely patterns indeed and fun to experiment with the settings !

Jan.

[bantri]

Once you get to like to arpeggiate with positive integers this site can give an impressive collection of patterns, most of them go outside the 0..127 range of keyboard notes but still a good source for inspiration.

http://www.research.att.com/~njas/sequences/index.html

[bantri]

Theoretically you can build any integer sequence if you have a basic module to cascade like we did analog cascading fm operators in the old dx7 days

The basic module would have those inputs

toggle button for dealing with only positive or positive negative math

rst(yellow input, pos edge) triggers the load of start value in the counter and resets the internal total steps counter to zero

clk(yellow input, pos edge) adds the increment value to the current value

start value(blue input) can be signed but if the math button is toggled for pos math loads the unsigned value to start counting

increment (blue input) can be signed but also obeys the positive math button

total steps (blue input) its our N and should be always positive and is linked to a yellow output that sends a pulse whenever it reaches the count
there should be a number box showing the current step

Current state (blue output) it holds the integer value until receiving the clock input for advancing to the next state

invert increment sign(yellow input, active high) if low adds the increment to current state and if high subtracts the increment from the current state after receiving a clk pos trigger

the bouncing behavior is not interesting to be included in this because it can be done by adding a clock divider in toggled mode to this module to keep it simple.

by cascading some of these modules in theory its possible to construct any integer sequence (my theory though)

[bantri]

For creating integer sequences the best option would be 2 modules instead of one as follows:

Sum module:
Start Value(Blue Bipolar signed input) Receives the initial value everytime a Rst is clocked

Inc Value (Blue bipolar signed input) Defines the increment to be summed everytime a Clk is clocked

Clk (yellow input, pos edge) triggers the sum

Rst (yellow input, pos edge) triggers the Start value load

Invert sign (yellow input, active high) inverts the sign of the increment when high (optional but useful)

Current State (blue signed output) presents the current sum state

Count module:
Counts from 0 to N-1
N-1 (blue input, rectified to be always positive) defines the point to cycle back to zero

clk (yellow input, pos edge) increment by 1

rst (yellow, pos edge) set counter to zero

LimitReach (yellow output, active high) raises everytime the counter reaches N

by interconnecting multiple copies of these two structures its possible to develop very complex integer sequences for arpeggios

i´ve included a simple structure to show the basis for them

---

PowerArp2005-Bantri.pch2
Description:		Download
Filename:	PowerArp2005-Bantri.pch2
Filesize:	1.83 KB
Downloaded:	1205 Time(s)

---

[oXo]

Really great, many interesting stuff here ...
Thanks for sharing your knowledge

[egw]

Thanks for the great ideas!
It will be a while before I get a chance to try them out.