Better Car Audio With Guitar Effects

Automotive sound is a huge deal; for many people, it’s the place to listen to music. Back in the 80s, you were lucky to get anything more than two door speakers in the front of the car. Fast forward to today, and you can expect a 10-speaker system in an up-spec’d family sedan.

[Josh] has a car, and wanted to improve the sound. In particular, the aim was to improve the sense of space felt when listening. A car is a relatively small space, and the driver sits in close proximity to the front speakers, so it’s difficult to get a good soundstage.

[Josh]’s approach was to create a “surround” effect for the car stereo, by feeding a left/right difference signal to the rear speakers. This was achieved by the use of a series of op-amps that buffer and then generate a mono signal that represents the difference between the left and right channel. For optimum results, [Josh] wanted to delay the signal being sent to the rear speakers, with a longer delay making the soundstage feel bigger, as if reflections are coming from farther away in a bigger room. To do this, [Josh] simply hooked up the signal to a Boss DD-3 Digital Delay guitar pedal – an off-the-shelf solution to an otherwise sticky problem. The DD-3 gives [Josh] a variable delay time with reasonably high fidelity, so it’s a perfect way to get the project done quickly.

The final piece of the puzzle is a filter. The difference signal doesn’t actually sound all that pleasant to the ears by itself, especially when it comes to transient high-pitched sounds like cymbals, so a lowpass filter is implemented to cut these higher frequencies down.

[Josh] made everything adjustable, from the filter to the delay, so it’s simple to dial things in until they’re just right, rather than relying on calculation or guesswork. The general idea is to feed the difference signal into the rear speakers at a low enough volume and with a subtle delay so that it adds to a general feeling of being in a larger room with the sound coming from all around, as opposed to listening to very loud point sources of audio.

It’s a cool project that we imagine would be very satisfying to dial in and enjoy on the road. What’s more, it’s a fairly straightforward build if you want to experiment with it yourself on your own car. Perhaps your problem is that you need an auxiliary input to your head unit, though – in that case, check out this Subaru project.

A Mini-ITX Atari 800

As a community has grown up around the 8-bit microcomputers of the 1980s, there have been some beautifully crafted rebuilds of classic machines to take advantage of newer hardware or to interface to peripherals such as keyboards or displays that were unavailable at the time. Often these have taken the form of small boards, or boards that are designed to follow the form factor of the original machine, and fit in an original case.

[mytekcontrols] has taken a different tack with his Atari 800 build, he’s produced an Atari clone designed to take the most popular upgrade boards produced by the 8-bit Atari community, as daughter boards. And he’s followed an existing form factor, though it’s not one from the Atari world. Instead, he’s made it as a mini-ITX motherboard of the type you may well be familiar with from the world of PCs.

He’s calling it the 1088XEL, because with a popular 1MB upgrade board fitted it boasts a generous 1088k of memory. It sports the original five Atari LSI chips, and manages the task without resorting to surface-mount construction.

The forum thread linked above is a long one that makes for a fascinating read as it deals in depth with the design of an 8-bit micro clone. But if you want to skip straight to the hardware, start at about page 13.

We’ve had more than one 8-bit Atari on these pages over the years. Most memorable though is probably this laptop.

Thanks [Lenore Underwood].

Hackaday Prize Entry: A Femtocell Repeater

For a Hackaday Prize entry, [TegwynTwmffat] is building a cell phone signal repeater. This sort of device is commercially available, but the options are either expensive or, as with some units available for $30 on DealExtreme, obviously noncompliant with RF regulations. This project intends to create a cost-effective, hackable device that works properly and conforms to the right regulations.

The core of this system is a LimeSDR transceiver. This is a board we’ve seen before, and it has a few interesting features. Basically, the core of the LimeSDR is a programmable RF transceiver with coverage from 100kHz to 3.8GHz. There’s also on-chip signal processing and USB 3.0 bandwidth to get the signals to and from a computer.

Right now, [TegwynTwmffat]’s focus is getting his LimeSDR up and working and figuring out how to set up a few radio blocks to do what is needed. There’s a great update to the project that showcases Pothos, and so far [Tegwyn] has a full-duplex repeater working. This is great work, and really showcases the capabilities of what software-defined radio can do.

Global Cyber Attack Halted: Autopsy Time

Friday saw what looked like the most dangerous ransomware infection to date. The infection known as WannaCry was closing down vital hospital IT systems across the UK canceling major operations and putting lives at risk.

Spread Halted?

It spread further around the world and almost became a global pandemic. Although machines are still encrypted demanding Bitcoin, one security blogger [MalwareTech] halted the ransomware by accident. As he was analyzing the code he noticed that the malware kept trying to connect to an unregistered domain name “”. So he decided to register the domain to see if he could get some analytics or any information the worm was trying to send home. Instead much to his surprise, this halted the spread of the ransomware. Originally he thought this was some kind of kill switch but after further analysis, it became clear that this was a test hard-coded into the malware which was supposed to detect if it was running in a virtual machine. So by registering the domain name, the ransomware has stopped spreading as it thinks the internet is a giant virtual machine.

Why was the UK’s NHS Hit So Badly?

According to the [BBC] Information obtained by software firm Citrix under Freedom of Information laws in December suggest up to 90% of NHS trusts were still using Windows XP, However NHS Digital says it is a “much smaller number”. Microsoft has rolled out a free security update to Windows XP, Windows 8, and Windows Server 2003 “to protect their customers”. There was much warning about XP no longer receiving updates etc, the 2001 operating system just needs to die however so many programs especially embedded devices rely upon the fact that the OS running is Windows XP, This is a problem that needs sorted sooner rather than later. There is still obvious problems facing the NHS as all outpatients appointment’s have been canceled at London’s Barts Health NHS Trust which happens to be the largest in the country. However [Amber Rudd], Home Secretary, said 97% of NHS trusts were “working as normal” and there was no evidence patient data was affected. Let’s just hope they update their systems and get back to fixing people as soon as they can.

Where Else Was Hit?

There was quite a few other places hit as well as the UK’s NHS including The Sunderland Nissan Plant also in the UK, Spanish telecoms giant Telefonica along with some gas companies in Spain. In the US FedEx was affected, France has seen production in some of it’s Renault factories halted. Finally, Russia reported 1000 governmental computer systems has been hit.

So is this the end for ransomware?

No, this infection was stopped by accident the infected are either still infected or have paid up, had they not included the sloppy code in the first place then who knows what would have happened. Microsoft had rolled out patches but some people/organizations/Governments are lazy and don’t bother to apply them. Keep your computers up to date, Good luck because we think we will be seeing a lot more ransomware malware in the coming years.

[Update WannaCry v. 2.0 has been released without the “kill switch”, We wonder what will happen now. Probably not a lot as the media attention has been quite intense so it may not be that big an infection however there is always a few who live in the land where news doesn’t exist and will go a long their day until BAM! Ransom Ware installed and pockets emptied.]

From Amritsar to Busselton; More World Create Day Stories

A few weeks ago, we took Hackaday IRL and into hackerspaces around the globe. This was World Create Day, a community effort to come together and build something that matters. Think of it as the pre-game for the Hackaday Prize, our online competition to change the world by building hardware. The groups at these hacker meetups have sent in pictures and reported on what they created. What happened during this worldwide hacker meetup? So much awesome stuff.

The SupplyFrame Design Lab

Did you know Hackaday has its own Hackerspace? It’s true! We have an eight-foot ShopBot, a Tormach, we just got a rig to do injection molding, and apparently, the intern is busy setting up a resin printer.

There are a ton of really talented people associated with the Design Lab, and they were out in full force on World Create Day. [Diego] from Deezmaker has been working on robot muscles and customizable linear actuators for a while, so that was obviously the focus of his World Create Day. Everyone needs mirrored LED-equipped welding/steampunk goggles, so that was [Rich Cameron]’s build, pictured to the right.

A fabulous time was had by all, but just because this was only one of three World Create Day meetups hosted ‘officially’ by Hackaday doesn’t mean it was the biggest or the best. There was plenty of fun the world over.

Amritsar, India

World Create Day is a worldwide event, so of course we had a few events in the second most populous country on Earth. [Inderpreet], [Shubham], [Simrat], and [Navjeet] put together a World Create Day event at the Department of Electronics Technology at GNDU Amritsar, their local university. A slew of people showed up, [Inderpreet] gave a talk on The Hackaday Prize, and much fun was had by all.

FabLab San Diego

The Fab Lab in San Diego also hosted a World Create Day event, Projects that made the cut included a real time, IRL closed captioning device. Think of this one as a universal translator, but only one language, with a screen. Or a voice to text thing running on a phone. Either way. Other ideas included an improved mobility cart, an underwater autonomous robot, wireless communication nodes, pressurized algae incubators, and a whole bunch more.

The folks at the San Diego Fab Lab also produced a short video of their World Create Day activities, you can check that out below.

Continue reading “From Amritsar to Busselton; More World Create Day Stories”

Say Hello to This Cortana Hologram

Halo’s Cortana enters the real world with this internet appliance. [Jarem Archer] has built an amazing “holographic” home for Cortana of Halo and Windows fame. The display isn’t really a hologram, it uses the age-old Pepper’s ghost illusion. A monitor reflects onto 3 angled half mirrored panels. This creates a convincing 3D effect. Cortana herself is a 3D model. [Jarem’s] wife provided gave Cortana her moves by walking in front of dual Kinect depth-sensing cameras. This motion capture performance drives the 3D Cortana model on the screen.

The brain behind this hack is the standard Windows 10 Cortana voice assistant. Saying “Hey Cortana” wakes the device up. To make the whole experience more interactive, [Jarem] added a face detection camera to the front of the device. When a face is detected, the Cortana model turns toward the user. Even if several people are watching the device, it would seem as if Cortana was “talking to” one person in the audience.

The cherry on top of this hack is the enclosure. [Jarem] 3D printed a black plastic stage. An Arduino drives RGB LEDs whenever Cortana is activated. The LEDs project a blue glue that works well with the Pepper’s ghost illusion. The result is a project that looks like something Microsoft might have cooked up in one of their research labs.

Continue reading “Say Hello to This Cortana Hologram”

Transparent 3D Printing?

Transparent plastic is nothing new. However, 3D prints are usually opaque or–at best–translucent. [Thomas Sanladerer] wanted to print something really transparent. He noticed that Colorfabb had an article about printing transparent pieces with their HT filament. [Thomas] wanted to try doing the same thing with standard (and cheaper) PETG, which is chemically similar to the HT. Did he succeed? Watch the video below and find out.

You can get lots of clear plastic filament, but the process of printing layers makes the transparency turn cloudy, apparently mostly due to the small gaps between the layers. The idea with the HT filament is to overextrude at a high enough temperature that the layers can fuse together.

[Thomas] wanted to create some clear parts and diffusers for lamps. The diffusers print using vase mode and the lamps he creates when them look great even without clear diffusers.

His first experiments involved layer height and extrusion rates. He tried to determine what was making things better and worse and modifying his technique based on that. There were also some post-processing steps he tried.

If you want to see what the Colorfabb HT parts made by someone other than Colorfabb look like, check out the second video below from [3D Printing Professor]. The prints he is making don’t look very clear until he does some post processing. Even after the post processing, it isn’t going to fool anyone into thinking it is glass-clear. However, the parts that Colorfabb shows on their blog post about the material do look amazing. Between the overextrusion used to prevent gaps and the post processing steps, [3D Printing Professor] warns that it won’t be easy to get parts with precise dimensions using this technique.

If you have a big budget, you could try printing with actual glass. There seem to be several ways to do that.