Ok, so I’ve good a pretty good sound system there. What now? It had been a long time since I’ve touched my turntables and I was missing the sound of vinyl quite a lot. Main reason I didn’t get the things out of their crates and connected them to a stereo is that I was simply too lazy and I didn’t find the right place for the setup in my room. My BassJump provided me with a bearable solution (both in weight and quality) for a while, but feeling the bass is something different.
Some time ago I was at an exhibition of Jay Gard and I decided I wanted to build something in that direction. So here it is:
The front panel features a rotary switch for off/line in/phono/bluetooth (bt not integrated yet) and the volume and bass pots of the sound system. to have more control of the sound I added a Behringer EQ . It adds quite some noise, probably the power supply, but it’s alright. All in all I’m very happy with what I got. Vinyl is back in the game and placing my monitor on top of the box provides me with a nice home cinema sound.
I am in the process of getting the building plans done in Fusion360 as an exercise and will provide them here if anyone’s interested.
]]>Features:
- DIN rail form factor
- AtMega2560 based
- USB/FTDI
- RS232
- RS485
- Ethernet
- 12V supply voltage
- nice to have: LED Indicators for IOs
Additional Features:
- Relays (230V)
- Power Outputs 5V/12V 1A
- Optocoupler IOs
- nice to have: all IOs optically isolated
- nice to have: debounced limited outputs for buttons
As I write I started pestering reddit with my questions on [possible circuits] and [requirements]. Let’s see what it leads to :)
]]>One could keep the whole thing extremely modular and design something around a master controller communicating with smaller boards that all have a certain purpose. But I want at least a certain functionality on one board to keep the wiring and communication programming as simple as possible. So currently I am thinking about building a stackable board that has the main processor and all the com I/Os on it that can be expanded by boards with extended features such as relays, decoupled outputs and such.
I was inspired by the [controllino]. I might as well buy one, but they seem to be in trouble with their part suppliers and I just can’t wait. Also, I want to do this by myself, learn stuff and make it available to everybody.
I did some research and stumbled over the [OpenPLC] project. I like what he did so far but I find the form factor a bit too clumsy for my purposes.
In the next weeks (and months, as these things tend to turn out) I will do some research/crowdsourcing as to different parts of the circuit and I will try to document it here. So whoever is up to such nerdy stuff: stay tuned :)
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Of course, as with many such initiatives and programs, working with them is not always easy. Especially for newcomers KiCad is hard to get into, as it starts with the fact that somewhere around summer last year no more “stable” versions were released (a good explanation can be found here, see also here). Nightly builds are available, but it’s hard to find out which one is actually working and you’d have to build them from source. I myself am incapable of doing the latter. The KiCad User Mailing List is a great help when it comes to that and other questions. The project website is anything but up to date and lots of information is scattered around the webs on various sites. But it is constantly getting better.
Sometime 2014 [KiCad.info] opened with an active [forum] and lots of tutorial videos. The forum is quite active and I just got a freshly built version for OSX (BZR5324) from there. Executables for windows and Linux can also be found here. The CERN has entered the project in 2013 and contributed a push&shove router and several other functions to the suite that were merged into the main branch this year. Great stuff! They also managed to set up a donation page so I could finally give some money to the project.
As you can see, not all footprints on my recent update to one of our machines are available…
If for some reason I someone is interested in using the 3D-display of the layout, I found a tutorial how to make VRML modules with Wings3D. Alternatively, I managed to build a footprint in Sketchup8, use an export-to-stl plugin I found somewhere to export the model (in inches), and open it with Blender to add textures/materials and then export is as .x3d (scale x10, Z-up, Y-forward). I am not sure it’s worth the trouble though, unless you are dealing with projects where every mm in your enclosure counts…
I did two introductory workshops to KiCad so far, main problem being the fact that everybody present had a different version with diffferent bugs and features installed. Now I finally found something what I would call a fairly up-to-date and stable version and my colleague XeN was so nice as to install it on a virtual linux machine I can make available to future participants to use.
This means: no more excuses. Stay tuned for upcoming workshops this year :)
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A recent (actually january feels _very_ far away by now) extended trip to Colombia could point prejudiced souls (and bots) in that direction. But actually it’s not the good old puffing, sniffing or shooting things up that keeps me from leaving messages to strangers on this digital outpost of mine. It is work. Plain and simple. It’s not an overdose, it’s rather the suddenly continuous supply, and thus consume, that distracts me from this representative duty. As of february I joined Fast Forward Imaging, developing and building devices for 360 degree product photography. Since then, tasks keep on coming in and I struggle to restrain myself to a healthy amount of work at a time. In the past, freelancing on a project basis, I used to take what I could get and finish it all as fast as I could, knowing I’d go into recovery once the supply ran out. Now I am sitting on a monster stash that will rather finish me than the other way around.
I hope this metaphor transports my struggle as well as the fun I’m having doing what I’m doing. For the past months there were no timeouts to write a little explaining article about what I was learning. Believe me though, I learned quite a lot, and one of these days I hopefully will find the time to write about it.
So stay tuned ;)
So viel Sand und keine Förmchen… Where did you spend new years eve?
Besides the lack of customization, code can become pretty confusing when having over 1000 lines to go through to find a certain function. Of course, this has been a problem of many programmers and thus there are already programs that offer good solutions to it. I went for [TextWrangler], a free version of BBedit and so far it helped me a great deal. I can define my own shortcuts for everything, have a dropdown menu of all my functions, can use markers and many more. I still use the Arduino IDE for checking and uploading my code. As far as I know there are ways to set up an automation for Editors like Textwrangler, too, but I haven’t bothered with that yet.
When first opening an Arduino project in TextWrangler, it will look like this:
(click on images for full resolution)
It’s missing all the highlighting of syntax elements such as commands and stuff. This you can change by installing a .plist file that contains all the definitions for the code. I found that one for the Arduino on [Github]. This needs to be put in Textwranglers “Language Modules” folder. On Mac, you have to right-click on the TextWrangler file in your Programs folder and choose “display contents”. You find your Language Modules folder in there. Windows users better check with the [TextWrangler] website (sorry).
Once the .plist file is in place you’ll need to (re)start Textwrangler. Then go to TextWrangler->Preferences->Languages and under Custom Extension Mappings associate .ino files with the Arduino language.
When next opening your file, it should look like this:
You can see that there is a dropdown menu with all the functions in the file. You can also minimize and expand those functions for faster scrolling.
You will still need the Arduino ID to upload what you edited. For that you open your file in Arduino. Then in Arduinos Preferences you check “use external editor”. This will make the Arduino code window appear grayish and prevent you from editing the code there. Whenever you upload or check your code now, the Arduino IDE will reload the file automatically and then perform the operation. This means you have to save your TextWrangler file before uploading. But, of course, you can keep it open all the time.
That’s about it. I hope this was helpful.
]]>In the last months I started working on some of the more tedious tasks such as cutting, crimping and soldering connectors to 100 speakers and then mounting them into the framework. Then I started assembling them but thought better of it. At the moment I am missing a PCB that does the pre-amplification of the audio as well as converting the Arduinos signal voltage levels (0-5V) to those of the rest of the circuit (+/-6V). Such a circuit already exists, of course, but not in a format that would fit in my construction. Realizing how much cables actually have to be connected inside the Diskokugel, I decided not to assemble it temporarily because it would take ages to disassemble it again. So you will have to wait until I got around to design that PCB and ordered it.
Until then these 2 images will have to do:
Audiopanel is an enhanced version of the [audioweb 0.1] I installed 2 years ago in my room. It’s a panel of 14 small speakers that switch the sound around like my [Diskokugel] will one day do and also is backlit by rgb-LEDs. It also has a “stereo mode” where 6 speakers each work as left and right channel. The lighting can be controlled in hue, saturation and brightness. Right now this is all done by hand, but in the future I hope it will all work via bluetooth.
What makes me proud is I made this mostly out of stuff I had lying around in my workshop somehow. I took electronic from older circuits and some broken boards and made it up as I went on. That’s why the stuff in the back looks so “modular” ;)
The whole rgb part still has some glitches. I used an HSVtoRGB patch I found in the [Arduino forum] based on formulas acquired [here] but it doesn’t seem to check out comletely yet. Also, since there is no separate GND for analog and digital signals in my circuits, the audio signal can have quite an influence on the dimmer when turned on loud. But I decided this to be a feature ;)
Using the stuff that also powers my Diskokugel, I learned quite something about the circuitry again. I know now that I could have saved my time trying to make it [louder] with a different amplifier setup by simply experimenting some with the existing pre-amp. There’s more headroom here :) Also the issue of the separate GNDs leaves me a bit concerned how this whole thing will work out inside the ball itself. We’ll see…
]]>- I started working as a Hardware Developer for [Fast Forward Imaging], designing pcbs for their machines
- my laptop got stolen
- I continued to design the next generation of [kwäek.control], but after a brief test had to realize, I’ll need to start over.
- my father had a stroke (he recovered fast, but I was quite thrown out of balance)
- I got deeper into Arduino- and C-programming
- I had one of the most relaxing holidays of my life, spending a week on a houseboat
- I lost my purse, keys and sketchbook and someone used my EC-card to relieve me of my hard earned money the same day
- I continued to work on [Diskokugel], starting an actual assembly of the ball
- I stated building a panel with speakers that uses the Diskokugel technology to have a decorative system replacing the [cable salad] that infested my bedroom wall about 2 years(!) ago
The loss of my sketchbook is what will affect this blog the most. It contained over a year of ideas, concepts and documentation. In the last weeks hardly a day went by without me missing some information out of it…
Anyway, all this I write to prove to the world that I still exist and keep doing the good stuff. Some of the things that happened were somewhat unpleasant (Ha! Ok! Let’s be honest: people have been driven to axe murder with less) but let me tell you: I am happy and healthy. And, as always, I promise I will write more often in the future. So stay tuned!
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]]>– I got fresh PCBs in from Seeedstudio and soldered 14 of them
– then I did a test with 96 speakers, after equipping all of them with crimped cables. Crimp till you cramp!
– I bought and tested a Bluetooth [Audio Module] and a [Bluetooth Serial Module] with Arduino attached. More about that in another article, though.
The PCBs came out well indeed this time and I was very happy to find that [c-base] has a reflow oven and hot air soldering equipment in it’s labs. This way the first half of what is to be Diskokugels intestines was soldered quite fast. While I was waitig there was plenty of time to cut, curl and strip of the isolation of 200 cables and the crimp and solder them onto 100 speakers. I get my lessons in Zen out of these tasks…
After that it was just a few more power and audio cables to crimp and then it was all ready for testing. Main objectives of this run were:
– check how the circuit acts on power-on
Diskokugel will have 200 amplifiers and they can draw _a lot_ of current. To reduce the current needed there will be measures to activate only a certain number at a time. That is however controlled by a controller that needs to boot up first and there is no control whats happening inside the switches of the individual boards in the main time. It turns out that as long as there is no audio signal, the circuits quiescent current is relatively low. That means I will use a relay to switch the audio in from ground to signal once the microcontroller has powered up. Easier than having to switch power on for one board after another :) 2 boards at full volume used about 1A at 12V. That makes about 150W for all Speakers at once. That also have to run through a voltage divider to provide +/- 6V and a virtual ground.
– check how serial communication works with a longer cascade of boards
The serial signal is put through 25 ics after all and there might be interferences. It works, but I had to set the SPI speed to 1/8th of the Arduinos clock speed. The fastest switching speed for 96 speakers was about 40ms this way. Since I had to lay everything out on a table, I had to use longer cables at some points. Once everything is mounted on the [icosahedron], it might work better.
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