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Archive for the ‘audio’ Category

We’ve all been there: after assessing a problem and thinking about a solution, we immediately rush to pursue the first that comes to mind, only to later find that there was a vastly simpler alternative. Thankfully, developing an obscure solution, though sometimes frustrating at the time, does tend to make a good Hackaday post. This time it was [David Wehr] and AudioSerial: a simple way of outputting raw serial data over the audio port of an Android phone. Though [David] could have easily used USB OTG for this project, many microcontrollers don’t have the USB-to-TTL capabilities of his Arduino – so this wasn’t entirely in vain.

At first, it seemed like a simple task: any respectable phone’s DAC should have a sample rate of at least 44.1kHz. [David] used Oboe, a high performance C++ library for Android audio apps, to create the required waveform. The 8-bit data chunks he sent can only make up 256 unique messages, so he pre-generated them. However, the DAC tried to be clever and do some interpolation with the signal – great for audio, not so much for digital waveforms. You can see the warped signal in blue compared to what it should be in orange. To fix this, an op-amp comparator was used to clean up the signal, as well as boosting it to the required voltage.

Prefer your Arduino connections wireless? Check out this smartphone-controlled periodic table of elements, or this wireless robotic hand.

Effects pedals: for some an object of overwhelming addiction, but for many, an opportunity to hack. Anyone who plays guitar (or buys presents for someone who does) knows of the infinite choice of pedals available. There are so many pedals because nailing the tone you hear in your head is an addictive quest, an itch that must be scratched. Rising to meet this challenge are a generation of programmable pedals that can tweak effects in clever ways.

With this in mind, [ElectroSmash] are back at it with another open source offering: the pedalSHIELD MEGA. Aimed at musicians and hackers who want to learn more about audio, DSP and programming, this is an open-hardware/open-software shield for the Arduino MEGA which transforms it into an effects pedal.

The hardware consists of an analog input stage which amplifies and filters the incoming signal before passing it to the Arduino, as well as an output stage which does the DAC-ing from the Arduino’s PWM outputs, and some more filtering/amplifying. Two 8-bit PWM outputs are used simultaneously to make pseudo 16-bit resolution — a technique you can read more about in their handy forum guide.

The list of effects currently implemented covers all the basics you’d expect, and provides a good starting point for writing custom effects. Perhaps a library for some of the commonly used config/operations would be useful? Naturally, there are some computational constraints when using an Arduino for DSP, though it’s up to you whether this is a frustrating fact, or an opportunity to write some nicely optimised code.

[ElectroSmash] don’t just do pedals either: here’s their open source guitar amp.

DriveInSpeakersOpener-8 copyEver used a drive-in movie speaker? Build your own and listen to your tunes in retro style.

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The post Revive Old Drive-In Speakers with a Modern LED Twist appeared first on Make: DIY Projects and Ideas for Makers.

A stock Arduino isn’t really known for its hi-fi audio generating abilities. For “serious” audio like sample playback, people usually add a shield with hardware to do the heavy lifting. Short of that, many projects limit themselves to constant-volume square waves, which is musically uninspiring, but it’s easy.

[Connor]’s volume-control scheme for the Arduino bridges the gap. He starts off with the tone library that makes those boring square waves, and adds dynamic volume control. The difference is easy to hear: in nature almost no sounds start and end instantaneously. Hit a gong and it rings, all the while getting quieter. That’s what [Connor]’s code lets you do with your Arduino and very little extra work on your part.

The code that accompanies the demo video (which is embedded below) is a good place to start playing around. The Gameboy/Mario sound, for instance, is as simple as playing two tones, and making the second one fade out. Nonetheless, it sounds great.

Behind the scenes, it uses Timer 0 at maximum speed to create the “analog” values (via PWM and the analogWrite() command) and Timer 1 to create the audio-rate square waves. That’s it, really, but that’s enough. A lot of beloved classic arcade games didn’t do much more.

While you can do significantly fancier things (like sample playback) with the same hardware, the volume-envelope-square-wave approach is easy to write code for. And if all you want is some simple, robotic-sounding sound effects for your robot, we really like this approach.

The HackadayPrize2016 is Sponsored by:

Filed under: Arduino Hacks, digital audio hacks, The Hackaday Prize

It’s just a little past Halloween, but Adafruit’s talking dog collar, modeled after the movie Up, is still a nice fusion between crafting and hacking.

One reason that Adafruit is so popular is that every time they sell us something, they give us some of the worlds best tutorials and libraries for free. For this project they’re using their Bluetooth LE board and their Audio FX board with a few more mundane vitamins to construct the collar. We’re sure the enterprising hacker could find alternatives if they so choose.

The collar is made of leather and 3D printed props. They went with alkaline batteries rather than lithium, to keep their doggy companion a little safer. All the electronics are hidden under the various props and the wiring is routed behind the belt. To control the app, the different sound bytes are mapped to buttons on their Bluetooth-to-serial phone app.

It’s a good starter tutorial, and the concept applied differently would definitely be good for at least one good prank on a coworker or friend.

 


Filed under: Arduino Hacks

[Captain Credible] is a chiptune music artist. He wanted to release an EP, but a regular old em-pee-three was too lame for him, so he made a tiny board with a coin cell, an ATtiny85, and a 3.5mm socket on it.

Rather than just writing some code to generate the tones for a pre-composed song, his “Dead Cats” EP generates the music itself. Using the arduino-tiny library, which adds the tone() function to the ATtiny, he has the chip pick its own time signature, key, subdivisions, and tempo. The melody and drum beat is randomly generated into an array. In addition to that, there are some code “one-liners” which insert unique sounds. After that the code just loops through the music.

If you don’t like the song, simply unplug the audio cable and plug it back in. The 3.5mm jack he chose has a built-in micro-switch, so the board is only powered up if someone is listening. If you’d like to see the circuit diagram, purchase the EP, or take a look at the code, all of that is available on his site.


Filed under: Arduino Hacks, musical hacks

ns1

We’ve been playing with NS1 Nanosynth in the last few weeks, when it first appeared under our radars on the Christmas’ Gift Guides (while going sold out in few days, after Synthopia blessed it with this interesting review).  It’s a hackable and customizable analog synthesizer coupled with an Arduino Micro platform.

Personally, it was one of my first steps into modular synthesizers. Nice sounds, easy approach. Peter Kirn is perfectly picturing this amazing compromise here!

Synths: they’re fun to tweak and play. Modulars: they’re fun to patch. Arduinos: they’re fun to hack. Small things: they’re fun to carry around.

But how to track patches? How to share sounds with friends? I was playing mainly with my son, and managed to print out a paper sketch depicting all the different pinout of the synth. I wasn’t satisfied with that, I needed more!

I started writing Sound Machines, about new patches, more sounds. It turned out I made a Fritzing part out of the Nanonsynth, and we started sharing each other patches. This repository holds them, and this is a short review of the best. Enjoy!

 

Here you can listen to the envelope Generator (ADSR) in action:

 

Want to add your very own sounds? You can either add it to their repository or comment here!

Mag
10

Embroidered Nyan Cat Brings a Meme to the Real World

adafruit, arduino, arduino hacks, audio, audiofx, cat, embroidery, Github, LED, meme, nyan, nyan cat, Sewing Commenti disabilitati su Embroidered Nyan Cat Brings a Meme to the Real World 

Have you ever come across an Internet meme and just thought to yourself, “I have to bring this into the physical world!” Well [0xb3nn] and [Knit Knit] did. They decided to take the classic nyan cat meme and bring it to life.

The frame is 24″ x 36″. Many hours went into the knitting process, but the result obviously turned out very well. The stars include 24 LED sequins to add a sparkling animation effect. These were sewn onto the back of the work using conductive thread. They are bright enough to shine through to the front where needed. These connect back to an Arduino Pro Mini 5V board.

The Arduino is also connected to a capacitive touch sensor. This allows the user to simply place their hand over the nyan cat image to start the animation. No need for physical buttons or switches to take away from the visual design. An Adafruit AudioFX sound board was used to play back a saved nyan cat theme song over a couple of speakers. The source code for this project is available on github. Be sure to watch the demo video below.


Filed under: Arduino Hacks
Mar
04

mabos2-2

Social Vibes’ is a Masters Degree (MSc.) project, in Interactive Media by Cian McLysaght, at the University of Limerick, Ireland. They shared with us their project, running on Arduino Uno, composed by a physical artifact designed and created specifically for an installation adopting the fundamental sound mechanisms used in a vibraphone, know also as a ‘Vibe’:

The instrument consists of twelve musical tones of different pitches. The music created on the instrument is derived from a continuous stream of input via multiple users on Twitter and the explicit interaction from Twitter users, tweeting the instrument directly to the project’s, “@vibe_experiment” Twitter account. Data associated with the emotional status of Twitter users, is mined from the Twitter network via Twitter’s open source, application programming interface (API).

For example if a user tweets “The sun is out, I’m happy”, the code I’ve written will strip out key words and strings associated with the user’s emotional state, within the tweets, ie “I’m happy”, and translate this to a musical notation. Mining Twitter’s API, allows a continuous stream of data. These emotional states are then mapped to specific notes on the physical musical instrument, located in a public space. The tempo of the musical expression will be entirely based upon the speed and volume of the incoming tweets on the Twitter API.

Twitter users who are both followers and non followers of the musical instrument’s Twitter account (@vibe_experiment) can tweet directly to the instrument and this direct interaction will be given precedence, allowing user’s who tweet directly to have their emotional state ‘played’. This allows users to hijack or take over the instrument and experiment with it in a playful manner, but also allows those with musical knowledge the potential to compose simple musical arrangements. When users are not tweeting the instrument directly, then the instrument will revert to mining the Twitter API.

To entice users to interact and observe the action of the instrument there is a live streaming broadcast of the instrument via Twitcam on the Vibe’s Twitter account. This is a live streaming broadcast of the instrument via Twitcam on the @vibe_experiment account. Twitcam, is Twitter’s built in live-streaming platform. This simply requires a webcam and a valid Twitter account.

The instrument constantly tweets back updates to it’s own Twitter account to not only inform people of the general status but also to engage users to interact directly with the ‘Vibe’.

vlcsnap-2015-01-23-15h12m16s206Just for fun, I designed my own variation of a treasure hunt game

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