The early days of electricity appear to have been a cutthroat time. While academics were busy uncovering the mysteries of electromagnetism, bands of entrepreneurs were waiting to pounce on the pure science and engineer solutions to problems that didn’t even exist yet, but could no doubt turn into profitable ventures. We’ve all heard of the epic battles between Edison and Tesla and Westinghouse, and even with the benefit of more than a century of hindsight it’s hard to tell who did what to whom. But another conflict was brewing at the turn of 19th century, this time between an Indian polymath and an Italian nobleman, and it would determine who got credit for laying the foundations for the key technology of the 20th century – radio.
Portable Media Players are great for listening to music on the go. At home though, using headphones may not be the most convenient or comfortable option. [decpower] didn’t have a stereo to connect his iPod to. Since he didn’t want to shell out a bunch of money to buy one, he decided to build his own iPod dock and powered speaker combo.
The case is made out of plywood: many, many layers of plywood. Each layer of plywood was cut out using a laser cutter. Unlike most speaker cabinets that have a distinct boxy enclosure, this unit is mostly solid with cutouts in each layer only where voids were designed to be. [decpower] tried to replicate the Bose Wave Radio internal sound passages. Up top a dock slot complete with a 30-pin connector makes connecting an iPod super simple.
Unfortunately, [decpower] doesn’t say what he’s using for an amplifier or where his speakers came from. He does indicate that there is an internal battery for powering the setup and it appears there is a volume knob out back. Regardless, the final project looks pretty good and [decpower] deserves some kudos for the unique construction method.
Bose, every salesperson’s favorite stereo manufacturer, has a line of WiFi connected systems available. It’s an impressively innovative product, able to connect to Internet Radio, Pandora, music libraries stored elsewhere on the network. A really great idea, and since this connects to a bunch of web services, you just know there’s a Linux shell in there somewhere. [Michael] found it.
The SoundTouch is actually rather easy to get into. The only real work to be done is connecting to port 17000, turning remote services on, and then connecting with telnet. The username is root.
The telnet service on port 17000 is actually pretty interesting, and we’re guessing this is what the SoundTouch iOS app uses for all its wizardry. [Michael] put a listing of the ‘help’ command up on pastebin, and it looks like there are commands for toggling GPIOs, futzing around with Pandora, and references to a Bluetooth module.
Interestingly, when [Michael] first suspected there could be Linux inside this box, he contacted Bose support for any information. He figured out how to get in on his own, before Bose emailed him back saying the information is proprietary in nature.
[Mansour] was disappointed to find out that his Bose QC15 headphones had a dead right channel. These headphones have active noise cancelling, which uses a microphone to capture ambient noise and digital signal processing to insert an out of phase signal. Since they’re quite expensive, [Mansour] was determined to resurrect them.
First, he determined that the right speaker had died, so he found a replacement on eBay. These were designed for a different set of headphones, but matched the impedance of the original Bose part. After replacing the driver, it seemed that the repair was a failure. The sound cancelling wasn’t working, and a the playback was high-pitched. As a last attempt, he potted the speaker with glue, to match the original construction. Much to his surprise, this worked.
The problem was that the new driver didn’t have sufficient sound isolation from the microphone, which is meant to pick up passive noise. This feedback likely caused issues with the noise cancelling DSP. A little glue meant a $20 fix for a $400 pair of headphones.