Derek Wang's NIME with Gideon D'Arcangelo Blog

video...

me playing bubbaboard

photo from NIME performance at Tonic last May

NIME Tonic Photos

here:

bubbaboarding and banjo? momma update...

talking to amos bloomberg about performing a duet with bubba and a banjo for the NIME performance at tonic. A duet will allow me to play acoustic and digital rhythm as well as play tones and have someone backing me up....

more details to follow after we meet and discuss further...

MOMMA - wow.. this speaker is starting to get pricey. learned from various discussion forums regarding leslie cabinets that the "sweet tremolo" sound the horn was spinning at 380 rpm!!! sooo fast... and found a motor that could potentially hit that at mcmaster carr, but the motor is extremely expensive ...$161 !!!
made the purchase with great pains and will show to roger baines (electrical engineer/former VP at johnson electric a major electric motor manufacturer). he's coming to speak this friday re: using electrical motors in your applications and is a family acquaintance...

talked to folks at making things about wiring a motor to the existing Teleo system, and David (don't know last name) there recommended using a MOSFET to deal with the considerable load (12v 5 amps 500+ rpm)..

will have the circuit built and will use PWM to control speed of the spin...

considered using a rotating belt like one used in a leslie, but for the sake of easier speed control and quicker design build will attach motor shaft directly to shaft that will be rotating.

concerns: The top of the pyramid of momma speaker will spin extremely fast... a little worried that this might be dangerous!!!

Ongoing issues:

1. sound and performance - honing and will fine tune with Amos with accompaniament

2. Momma speaker
- build issues described above

- Will need to find way to amplify (prob use old integrated amp stereo component for time being).

speaker pic and playing with different scales

Here's a pic of my foam board protoype speaker...

the top of the triangle will spin according to the speed of how much i tilt the bubbaboard... i am still just receiving the parts (woofer, tweeter, and crossover arrived today..waiting on slip ring before i search for a motor)... hoping for that "leslie" type effect.... i even found a slip ring .. or more precisely a "rotating electrical connector" from mercotac.. they claim it's better than a slip ring and the technology was created by none other than Don Leslie of Leslie cabinet fame...
If it all works out the speaker pyramid thingy will be called Momma to complement the Bubbaboard...

Scales - I am currently contemplating using one of the axes on the bubba accelerometer to dictate the type of scales/chords that can be played.... i will limit it to maybe three types per patch and find a way to clearly know how far to tilt the bubba to play what kind of scales/chords...

Bubbaboard- sounds, scales, tones, and speaker!...

with the bubbaboard prototype more or less complete, i've been focusing on the sound processing in MAX/MSP and have been playingn with a few ideas regarding amplification..

Sound processing - i have started to put together different types of patches to experiment with the Bubba...

1. the original patch - consists of high pitched frequencies that go down in pitch as you play in lower sections of the washboard...

2. less dampened sounds - playing with scales and tones that have more sustain in order to build layered sounds...

3. blues patch - working on a patch to play blues scales and perhaps chords...

Accelerometer - still hammering away how to utilize the X and Y sensor data ... currently using to increase vibrato modulation and pitch bend...

Amplification - for my Materials class, I have proposed to make a speaker (will require amplifier) that will try to emulate the mechanical vibrato effect of a leslie speaker. The spin speed will be midi controlled, and am thinking of using x or y axis data from the accelerometer to control the spin speed.. still hammering out the mechanics, so sketches and more details to follow... i also have a photo of the foam core prototype of the pyramid shaped speaker that i made which will be posted as well...

getting ready for the prototype presentation

here is the first pic of the bubbaboard...from the back.... three teleo mounted devices on the top which will read sensor data (IR ranger, accelerometer X and Y, and cross fader switch)... red electrical tape mounting a piezo contact mic in the middle towards the bottom of the washboard...

can't see it but there is also a IR ranger mounted to the wood leg that is connected to the bottom two legs perpendicularily... the IR data tracks hand movements and will potentially help with pitch control...

a close up of the cross fader that is attached to the left side...

a close up of the piezo mic in the back... attached by red electrical tape..

a close up of the teleo devices.. from left to right... USB unit, Multi I/O unit, and power unit...

and finally the accelerometer mounted in mysterious substance (badly molded silicon rubber)... looks like a chunk of ham that's fallen on the ground a bunch'a times..

Playing with piezo's..

focusing on the piezo sensor to see what kind of data i can analyze in max...

made a piezo out of radio shack components using the
instructions on this site

stil in the process of playing with the BONK object so no exciting news yet..

other news...

Teleo MIDI - I/O Box.
made by:
making things

Purchasing this box created quite a moral dilemma. The box is essentially two PIC chips each mounted to two components with an additional component to handle power. While I could over time make these modules (albeit not as professionally), I really want to focus my time in getting the data from sensors and manipulating and analyzing in MAX/MSP for sound generation. I just feel really guilty as ITP culture dictates that everything is DIY. Not to mention that this TELEO box is relatively expensive (250 dollars). Not I-cube expensive, but expensive nonetheless. Regardless, what's done is done and now I have put off PIC programming for another day...

Teleo specifics:
As mentioned the intro system is comprised of three components

1) I/O component is used to manage the I/O.. analog and digital..pwm

2) data out component sends out data via USB to MAX. Making Things provides a set of MAX objects to manage sensor data.

3) power supply component.

I will post photos in my next submission of the system.

Still looking at Eric Singer's I/O box for comparison as well but need to focus on hashing out details of sound generation...

still bubbaboarding...playing with additional controls

primarily focused on sound and sound control in MAX/MSP while I await the delivery of the teleo MIDI I/O box...yes very un-ITP to not build your own microcontroller... but given the tight time frame, I was weary of setting up my own PIC chip to interface with MIDI. The Teleo from www.makingthings.com in San Francisco is essentially a PIC chip mounted to a PCB with different modules for In's and Out's (the set I bought comes with a I/O module with ADC's, Digital Inputs and Outputs and PWM for motors... can't remember how many off the top of my head for each, but more than sufficient for the instrument.. the whole set with MAX externals is 250 dollars... so cheaper than an I-cube but very pricey nonetheless... I hope to use it for other applications and when I get time to get savvier with the PIC I can always hawk it to the phys compers who are scared of PIC programming ;)

Current Status
Playing with different MAX objects primarily BONK and fiddle which are real time audio analysis objects for percussion and pitch respectively. Thinking about using a contact Mic to analyse the muted washboard sounds. Obviously there will be little pitch, but wondering if Bonk will be of use.

IR Rangers - Still experimenting... pending outcome of how they work with Teleon... could be used to play chords/scales...

POTS-
Planning on incorporating pots for:
Volume
Tremolo/Vibrato
TBD - maybe just to always have a third option for something I discover in MAX

Buttons -
Looking at arcade style buttons for:

Sustain - of chords/scales generated in MAX/MSP

Activation - perhaps holding button down will tell MAX to generate chords/scales in order to facilitate play b/n acoustic and digital generated sounds...

REASON Adapted -
Hoping to use some of Dan Palkowski's patch to Reason Subtractor rack item for those 70's-ish synth sounds...

Concerns:
Scale and Chording - While I am using an accelerometer for Pitch bending (tilt the washboard to bend pitch)... i'm still not sure how I"m going to play notes/scales/chords with the IR ranger. Really hoping the BONK Max object will give me some direrction....May have to focus on ambient type sounds instead... for the time being would still like to have it as a solo instrument in addition to accompaniament though...

bubbaboarding

So in case i haven't mentioned got the washboard (10 bucks from hardware store somewhere on Washington Ave near Tom's diner in Brooklyn).

Now I have something physical with which I can test out sensors and see how the sensor data goes...

so current progress:

MICROCONTROLLER - Given the compression of time, I really have started leaning towards the BX chip primarily b/c I am not sure if I can get up to speed quickly enough on the PIC, particularily since I also need to focus on receiving MIDI data into MAX/MSP and processing it.

Eric Singer is also offering a midi I/O box for beta testing... it costs 125 bucks (discounted for beta testers) but he says it may not be available for evaluation for another two weeks...

here's an email snippet about Eric's miditron box:
I am beginning public beta testing of a new MIDI I/O box that I have
created and will be selling shortly. It is called MidiTron™, and it
provides 20 terminals of user-configurable i/o, in any combination of
digital input, analog input (up to 10), digital output and analog
(pwm) output.

so intriguing but the timing may be poor for my bubbaboard...
also looking at the teleon from www.makingthings.com which is essentially a PIC mounted with the logic already programmed for sensor inputs and MIDI output...

MAX/MSP and SOUNDS - Have been playing a lot with RM AM and FM synthesis for my Frameworks for Interactive Sound class... I am really digging the modulated sounds that are coming out of it and am curious how modulated sounds off a contact mic attached to the midi washboard would sound. i could perhaps then pitchbend the sounds depending on how I move the washboard around (sensed by accelerometer).

IR Sensors
Also playing with IR sensors to see if data will be detected off movements up and down the washboard...

Accelerometer and some sensing ideas

So thanks to John Bergren I have a 2-axis accelerometer from Analog Systems already mounted on a custom spec'd PCB express board. Still need to hook it up to a microcontroller.

This week's challenges:

What controller to use:
I am more familiar with the Basic Stamp chip than the PIC and am weary of the intiial cost of starting with the PIC (software/programmer is over 300 bucks). I want to have a setup I can use outside of school, and if I am resolved to using PIC chips in the future then that is something I have to seriously consider.

Sensors:
- Accelerometers - Def going to use this sensor for either pitch or pitch bend.

The big problem is what I am going to do to detect motion and vibration on the washboard corrugated metal surface:

1. Capicitance sensors - Jamie Allen thinks from his past experience that these sensors would be way too slow and...

2. piezos - may find all the noise from the washboard too noisy...

3. homemade sensor - also suggested by mr. allen (i do whatever he says :) )
constructing metal objects on a block of wood and using spoons equipped with sensors to sense how quickly they metal is passed by..

other sensors to research and either consider/eliminate:

1. contact mics

2. metal, or polymer that has variable resistance as my spoons/thimbles move up and down

SOUNDS:
another big challenge.. still want to combine rhythms and tones.... argh...

Concept Ideas pt 2 - The Bubbaboard

My Concept

The Bubbaboard

The Bubbaboard will be based on the washboard, a standard accompaniment instrument in Zydeco music.

The traditional Zydeco washboard has evolved from a traditional washboard:

Initial Concept Presentation ideas

Still thinking about a percussion/melodic instrument based on a washboard paradigm (either an actual washboard or something that senses movements like spoons playing on a washboard)...

part of the inspiraton comes from mark argo's instrument...

I want to create something with an "old-time" traditional feel yet will make sounds and tones that are original and unique.

One of the main debates was whether or not to make a new instrument out of an existing one. A washboard in particular, as pointed out by Gideon last week, already makees a significant amount of noise.

So I am thinking about still using a real washboard, dampening it somehow, and using sensors (hall, IR... not sure what yet) to capture the movement of mallets (spoons perhaps) moving over the washboard creating percussive rhythms.

I would also like to create something tonal as well....

anyway.. my inital thoughts...