Adding a multitimbral MIDI SoundChip to Arduino
Part two of a multi-part blog post on building a MIDI synth instrument.
The basic idea is to use 3 Arduino's to make a visual / sound instrument.
Arduino 1) Send control data.
Arduino 2) Generate wav audio from MIDI input.
Arduino 3) FFT EQ visualization.
LET'S BEGIN !
Solder on Stackable headers.
Careful to try get the headers aligned. ProTip is to put your stacking headers to the table & set an old shield underneath with pins facing up (into the receptacle end of the headers) to line them up for easy soldering. So a shield underneath this one in the photo below.
I just went for it & tried to hold it still, so stacking headers came out a tiny bit wonky, but the pins still lined up perfectly with Arduino, so yay!
The chip driving this board is the VS1053, essentially the brain / heart / guts of a MIDI Synthesizer. I will admit one of my main reasons for building this is playing DOOM and other DOS games which can send MIDI to the shield. Modern update for an old SoundBlaster16 or Roland Sound Canvas.
And we're done.
Stayed tuned for the next episode.
Control MIDI the old fashioned way. With knobs.
Part one of a multi-part blog post on building a MIDI synth instrument.
The basic idea is to use 3 Arduino's to make a visual / sound instrument.
Arduino 1) Send control data.
Arduino 2) Generate wav audio from MIDI input.
Arduino 3) FFT EQ visualization.
Yes, it would be simper to do this with an Arduino Micro (or RPi3) + a teensy for similar functionality. But not as much fun.
LET'S BEGIN !
Soldered the MIDI jacks first. Make sure to solder them flush to the board.
Since they need to withstand plugging cables in & out, good to get them perfect. OR make a case which takes some of the brunt of the insertion force.
Soldered the rest of the surface components. This kit is relatively quick to assemble.
The variable resistor traces are quite close to the push buttons so watch out for that. I may look at these solder joints again under a microscope.
So theoretically you should use stackable headers, but the SparkFun Instrument board which I'll be sending signal to (from this) is pin incompatible, so using breakaway headers. Measure the length of the MIDI shield's headers & gently snap off what you need with a set of needle-nose pliers.
Ideally you have an old unused shield around to act as a brace for soldering the header pins, but in a pinch can use a breadboard to keep pins in line.
Snap Male headers attached.
All done !
Really useful additional tutorials
Stay tuned (pun!) for the rest of the build of the Hydra instrument !
A new regular Blog series.
Featuring quick overviews of the various platforms Elmwood offers.
Intro to Wearable/Sewable Electronics aka 'e-textiles' : Adafruit.
Common Elements:
Different Product lines:
Older models, aka 'counting all the chickens' :
There were non-CircuitPython ArduinoIDE 'C' based versions of most boards in the past.
Important People in wearables from Adafruit :
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Adafruit originally went big with wearables with the FLORA arduino based product line. They have been slowly transitioning to CircuitPython based boards such as the Circuit PythonExpress, Gemma m0 and Trinket m0. However, if you WANT TO, you can still flash the firmware on those & use good old Arduino 'C'.
'Neopixel' is the most commonly promoted library which can drive LED strips to make things like the FIREwalker sneakers One could as easily start with Gemma and work with that for quite a while before needing the expanded feature set of the Circuit Playground Express.
Circuit Playground Express Educators Pack
Gemma talking toy guts sound pack
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Performance :
A regular blog series featuring quick overviews of the various platforms Elmwood offers.
Intro to Wearable/Sewable Electronics aka 'e-textiles' with Lilypad.
Lilypad Ecosystem { SparkFun promoted Wearable platform }
Out of the Box :
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Featuring a novel 'protosnap' approach: you test your circuits on the board & then snap them off & sew into your project when ready.
 Lilypad has many kits & options.
Full range found here.
All Lilypad products are Ardunio IDE based. Kits have a very quickstart approach & can get going immediately. Protosnap kits generally don't require any programming, the other boards are more versatile.
We recommend you try some of the kit projects & then move to individual component based projects.
Individual Boards :
USB Based.
FTDI Based. * FTDI cable versions came before USB ProtosnapPlus boards.You'll need a FTDI cable for programming these boards.
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As much fun as the 1.0 hoodie was, realized could take it up a notch by adding a
That way it would flash along with the beat when you wear it to a concert or on stage.
We stock a 6v and a 12v. To drive one length of EL Wire you need to use the 6V.
high-brightness-aqua-electroluminescent-el-wire-2-5-meters +
el-wire-6v-sound-activated-pocket-inverter + a 4x AA Battery Pack
Before soldering anything, it's a good idea to make sure the circuit works with alligator clips.
From Left : EL Wire adapter to sound activated inverter to 4xAA battery pack.
The dashed white lines on the inverter go to the RED lead on the battery pack.
Then I cut some heat shrink tubing. Important to slide this on the wire BEFORE you solder it.
At this point realized I needed to strip the ends of the battery pack a bit more to get a good connection.
Attempted to do it 'old school' by rolling a boxcutter along the wire. Then found out it was Stranded Core and gave up to go find the excellent set of Hakko wire strippers.
If your wire is solid core you can get away with rolling it under a boxcutter, stranded core you end up cutting through half the strands & won't work.
Once you have the insulation cut, for stranded core, roll it off with your two fingers. This will twist the wire to make it easier to solder.
Tin both the leads
If I have very fine wire, rather than trying to horizontally solder them,
I will sometimes twist them together with needle nose & then solder that connection. Especially for clothing which will have more movement and torque on the joint.
Slide the heat shrink back over & apply light heat with a lighter or heat gun in smooth back & forth motions.
Don't hold the heat source in one spot or you may get smoke & eventually possibly fire.
Also the tube will only shrink so much, so use the right guage.
Success !
**Footnotes**
The hoodie being modded is a BetaBrand Reversible Disco Hoodie from San Fransisco.
For larger (non-hoodie) projects, If you want to drive 3+ meters of EL Wire, you would need to use
el-wire-12v-sound-activated-pocket-inverter + an x8 AA Battery Pack.
For the x8 you would have to cut off the barrel jack adapter & strip the leads a bit.
For a good sewing starter project, I decided to replicate Adafruit's Tron Hoodie.
You only need a hoodie, needle & thread, & some EL Wire with a battery pack. No soldering involved.
Relatively straight forward, sew thread loops around the EL wire about every 3 inches.
To get a nice curve along the hood, use a tighter spacing of stitch.
Good idea to measure the inner length of your hoodie first as I ended up having enough EL wire to do half the back too.
A second consideration is if you want it inside the zipper or outside.
Inside you won't see half the EL if you zip it up.
I chose a reversible hoodie, so could wear it inside or out.
Sew the battery connector close to a pocket, so that can sit in there undisturbed.
Completed Hoodie :
The standard EL Inverter has 3 modes for the EL Wire.
Fully lit, flashing & seizure mode.
Good times.
Intended as a companion to read before the OFFICIAL BUILD GUIDE
Some additional hints on things to be aware of during assembly.
Unboxing.
Use the buttons to prop board up to make it even for soldering.
Little containers are great for organizing kits with many parts.
You need to save your component lead 'off-cuts' so clip them off FACING AWAY from you into a small box.
Careful to distinguish between similar LOOKING parts.
Can use needle-nose pliers to bend leads out a little to make it easier to mount on the board. Be very gentle.
When preparing to insert the IC, gently & SLOWLY roll / bend it against a firm non-static, non-scratch surface. This will make the pins easier to insert.
*OPTIONAL / NOT RECOMMENDED*
I pulled the battery JST connector out to make it easier to move the board around for soldering. It was firmly in there, so used two sets of pliers to remove. IT's VERY easy to DAMAGE your board like this, so only do this step if you are super confident in your abilities. Not recommended & NO REFUNDS if you damage your product. Mini linesman (square pliers) must be parallel to sides of JST mount on board.
If you haven't recently trimmed your fingernails, I'm sure a motivated person could do it without tools as well.
*/ END OF OPTIONAL STEP*
A real PROTIP is to use tools to prop components FLUSH to the board from underneath & solder them in on top.
This will keep it even when you solder.
The serial programmer, in this instance.
The LCD will no longer let you sit it entirely flat.
The Volume & Brightness Dials ESPECIALLY must be soldered in flush, or they will not be able to turn as they will hit the LCD. Check it on both sides to make sure no gaps are under one of the Dials connector legs.
*OPTIONAL*
Use a microscope (or magnifying glass) to make sure all your solder joints are not overlapping.
For the curious, I viewed the USB microscope output on Ubuntu using Cheese App. No drivers were necessary.
*/ END OF OPTIONAL STEP*
Almost done...
Booting !
All that's left is the case assembly.
I used clear gorilla tape to affix the speaker to the back plate.
Can now play all the demo games on the card !
Remember to sleep!
*We had some extra colored buttons around the office, so used those to spice it up a bit. The standard kit comes with black buttons.
IF you hit any snags, check here first :
IMPORTANT NOTE : Had a brief panic it was dead, as I accidentally shut it off while it was loading a game. When you turn it back on, the screen will be lit, but no content shown.
If this happens to you, follow the C-button (top left) reboot method here :
https://www.makerbuino.com/build-4-some-more-soldering/
BE PATIENT while games are loading, up to 30s each.
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