Portable Audio Hacks

101 Articles

GPS Audio Tour Brought To You By Surface Speakers

September 6, 2011 by 8 Comments

The team at Eschelle Inconnue wanted to “trace a sound cartography of Islam” in Marseilles, France, so they came up with a clever little GPS walking tour powered by an Arduino, MP3 playback module, and a surface transducer speaker.

The team used a Processing app to define geographic areas where each MP3 file would play. An Arduino on the build queries a GPS module and selects the audio file from an MP3 playback module. This isn’t uncommon, and a lot of large outdoor museums (think battlefields) have similar setups.

Determining which audio to play at what location is fairly easy, but that’s not what makes this build special. Instead of simply hooking up a pair of headphones to the build, the team decided to use a surface speaker that turns just about any solid material into a speaker. From the writeup, this is supposed to, “diffuse sounds by giving the illusion to collect them, to listen to the words of the walls, the whisperings through the materials” but we think it’s just a great way to have several people listen to the same audio file at the same time.

PVC Boombox Is Not A Potato Cannon

June 16, 2011 by 14 Comments

After [Luke] built a suitcase mini-ITX rig for LAN parties he was left with one problem: he didn’t have any speakers and he didn’t want to use headphones. Not wanting to do something boring like a USB-powered speaker setup, he built a PVC Boombox.

Built around 3 inch PVC pipe, the boombox houses an off the shelf 15 W amplifier, bluetooth receiver, and charge controller. [Luke] found a deal on a dozen 1400mAh lithium ion batteries and despite the standard, “if you don’t know what you’re doing, don’t use lithium” trope commonly given as advice, he forged ahead anyway. [Luke] picked up a power converter that charges the batteries and provides some protection. The batteries are charged though wall power with a transformer and a huge cap scrounged from an ATX power supply.

[Luke] is pretty pleased with his boombox. Not only does it put out some decent quality sound, the battery life should be tremendous. It’s not a ground-up build, but we think it’s a pretty nice project. [Luke] will be taking the ‘boomtube’ to the Detroit Maker Faire next month, so if you see him make sure to say hi.

Portable SID Plays Chiptunes

June 3, 2011 by 19 Comments

[Markus] on the DangerousPrototypes forum came up with a great little SID player.

The SID was (is?) the awesome sound generation chip inside the Commodore 64, and along with Game Boys and NESs laid the foundation for the chiptune scene. We’re happy to finally see a small SID player that doesn’t resort to SID emulation or a relatively huge MIDIbox.

The SID player itself is a shield on a CUI32 PIC dev board. The PIC32 emulates the 6510 and 6526 CPU and CIA chips found in the Commodore 64. A small USB memory stick stores the High Voltage SID Collection and the file system is navigated with an OLED screen. [Markus] says that the player draws 370 mA, so he runs it off a small wall wart. Still, we’re wondering if it’s possible to run this off of an SD card with a SwinSID so power draw can be reduced and a fully portable SID player can be realized.

We’ve got a touch of nostalgia for chiptune and demoscene music right now, so we’re going to listen to some [Nelly Furtado] [Janne Suni] right now, but you can check out the video demo [Markus] posted after the break.
Continue reading “Portable SID Plays Chiptunes” →

Android Talks Pulsewave

November 10, 2010 by 41 Comments

Serial communications are a mainstay of digital computing. They don’t require much physical infrastructure and they exist in variations to fit almost any application. The behaviour of serial communications lines, varying from high to low voltage in a timed pattern, is analogous to a 1-bit DAC. Using a whole DAC for serial communication would be a waste in most cases, but the [RobotsEverywhere] team found an exception which you may have encountered already.

Since the audio output of the Android is accessible and addressable, [RobotsEverywhere] wrote source code to use the left and right channels as separate serial communication lines. This circumvents the need to bust into the device and muck about with the hardware which is great if you want a no-risk hack that allows communications to an RS232 port. Any hardware on which you can write to the DAC (and control the sampling rate) is a potential target.

There are some external electronics required to convert the audio signal to TTL, but it’s not very complicated–a couple of comparators and change. You can see it in action after the break.

As a bonus, when you’re done for the day you can plug in your headphones and listen to the soothing poetry of pulse waves all night long.

Continue reading “Android Talks Pulsewave” →

Solderless Drawdio Terminally Implemented

November 9, 2010 by 5 Comments

So you’re stuck in a boring class and you can’t fight off the urge to hack something, even your pencil, to pass the time. Maybe you are performing a live electronics show and you drop your synth down a flight of stairs and all that you are left with is a handful of components, a screw terminal block and a pencil. There are thousands, perhaps millions of these kinds of situations and for each one the answer is the solderless drawdio clone by [Martin].

You may have seen the original Drawdio here before, a fun piece of technology that is simple enough to recreate. This latest approach would make an excellent introductory project for a hacking workshop seeing as the guide is straightforward and the lack of soldering would make logistics so much easier. The results are very similar to the original–check the video after the break. Continue reading “Solderless Drawdio Terminally Implemented” →

Chumby One Becomes A 3g Router

April 29, 2010 by 19 Comments

[bunnie] has taken a few moments to show us how to turn our Chumby One into a 3g router. As it turns out, there is an easter egg that allows it to communicate with certain models of 3g dongles. There’s no GUI for this trick, so you’ll be doing most of your configuration via SSH. That shouldn’t be a problem for this crowd though. The Chumby One just got a lot more appealing.

Classy Hard Drive Speaker Set

September 14, 2009 by 17 Comments

hdd_speakers

Hard drive speakers aren’t anything new, but they have yet to be done very professionally. Most hard drive speaker hacks are awesome, but aren’t meant to be a showpiece. [Oliver] took the opportunity to put together a set of 20GB drives and a custom-built acrylic case with a horizontal VU meter up front. The project is well-photographed and documented and can be recreated without the use of laser cutters or other expensive tools. The only thing it’s missing is an iPod dock!

Related: Giant bulb VU meter