Posts Tagged ‘Diskokugel’

Diskokugel Progress 10/13

Sunday, October 6th, 2013

Some months went by since I last updated on the state of my [Diskokugel] project. It might seem a never-ending story this one, but rest assured, I am getting there.

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:

Diskokugel Eyecandy

Wednesday, March 6th, 2013

To motivate myself (and to keep you entertained) I’ll show you some pictures of the recent progress.

With my bold head glittering from cold sweat I took a soldering iron and separated my nice round [Kugel wireframe] into segments again. Luckily that went well, if I ignore that I had to buy a new power iron because the old one broke for no apparent reason(it was exactly one! day over its warranty). To those elements I attached my freshly cut [mirror balls]. I also took the [useless PCBs] as dummies and attached the to the icosahedron inside. I then tried to figure out a pattern how to attach the speakers to the PCBs inside, which was a bit tricky because the cables wont be distributed evenly.

Anyway: having a party in our place there was a need to clean up and make things look good. As it turns out, putting a light inside the existing object makes it quite flahy. But see for yourself…

Diskokugel Ballroom

Thursday, January 17th, 2013

Pushing the [Diskokugel] forward, I cut 120 christmas balls in half to serve as bodies for the speakers. It took quite some time, but they make for some nice self portraits :)

cutting some balls

I love patterns and textures...

Me, a landscape

Better not an Omen

Friday, January 4th, 2013

Well, here’s for a happy new year: for christmas I ordered myself a series of pcbs to finally get the [Diskokugel] running. After spending 5 hours getting the goods out of customs I had to realize that the pcbs have no solder pads. Instead, they’re coated in paint entirely. I tried to get the paint off with acetone and a steel brush, but there’s no way I can use these…

I wish you all more luck in the new year ;)

try to solder this...


Diskokugel News

Thursday, May 10th, 2012

As promised, Christian and I went to testing the new Diskokugel board last weekend. We started by soldering one of the LM4863s he bought on eBay to the new board. Christian had his concerns whether the stuff he bought from Hongkong would actually work :) During the last week I finished soldering most of the parts to board (my first smd project!).

Next week I will test the board as a whole to determine whether the actual delay of 6 months was worth it. If it turns out that the new design doesn’t meet my requirements I will simply go back to the old design and continue there. Progress needs to be made!

testing the lm4863

my first smd board!

Trying to make Diskokugel louder

Tuesday, November 1st, 2011

After my first experiences with the [Diskokugel] circuit building [Audioweb] and [AudioSphere] I tried to optimize the circuit for further use. That means I tried to look for a way to get some head room with the volume, since the current design didn’t quite satisfy me volumewise. I discussed the problem with Christian and we did some experiments using a [TDA7053a]. Not only would the TDA make a higher amplification available. Working on 5V instead of +/- 5v, as the transistor circuit works right now, it would have rid us of one power line that has to be transferred into the turning ball via a sliding contact. Also, soldering two chips on the board would have been much faster than soldering those 16 transistors.

The TDA7053 has a DC volume control input, which made us hope that we would simply connect it directly to the 4094 register to switch it on and off, making the 4066 switch obsolete. Unfortunately that didn’t work. The 7053’s offset voltage rises with the applied control voltage, thus producing a crack at the output when raised rapidly. Ultimately we got the thing working by keeping the control voltage at ~0.7V and switching the audio signal on and off with the 4066. However, since in this version all amps are constantly active, I am afraid the whole system would be prone to interferences and the power consumption would be very high. I had a very hard time testing the whole setup. I don’t know if it was my breadboard or whatever, but something started oscillating regularly and there was never a setup tat was save from that or other interferences. Christian told me however that he got something working.

I am not sure how to proceed yet. I think I will stay with the old circuit for now and see how far it takes me. After all, one result of the experiments with the TDA was that a higher volume makes it harder to locate the source of the signal. That would be sort of counter productive. It also shows that there are possibly limits to the use of this whole technique…

Audioweb 0.1

Monday, September 5th, 2011

As a special gimmick for my birthday party i used the elements of [Audiosphere] to build a web o 6×6 speakers on a wall in my room. The sensation is, of course, a different one and since its now totally at hand, I will do some more experimenting in the next weeks.


the cable length of the sphere didn't fit, so it doesn't look perfect yet. I still like it :)

AudioSphere for PDCON

Sunday, August 14th, 2011

Having introduced the [Diskokugel] project at Berlins biweekly [puredata] [user group], I was asked to build an installation for the finalizing event in Berlins [LEAP] gallery. Being busy doing technical coordination for the [Über Lebenskunst Festival] this was quite a task.

I used the five prototype circuits to build a walk-in sphere of 40 speakers. The speakers were attached to nylon strings stretched from the ceiling to the ground, so you could bend them aside to step in. In an effort I provided a crude interface in PD that provided a joypad for people inside the sphere to select different programs, such a random, sound going in circles, etc.

Contentwise, we had placed a call for content, which resulted in one piece that was handed to me and which worked quite well. I have yet to get the adress of the composer to thank him again ;)


The result was quite to my liking and so was the feedback (apart from nobody understanding the interface, but in the end that didn’t matter much). The sphere was fun to use. I personally found it pretty dizzying standing inside the speakers while the sound came from a different direction every 25 milliseconds. Unfortunately, as of now there are no pictures to show. The  installation stood at LEAP only for two days, in which I had forgotten to bring my camera. Hopefully I will find someone of the PDCON who made good ones.

[UPDATE: pictures of the building process and a picture from a mobile phone (thanks ckp and astring!)]

a picture by astring

in action. the nylon-strings could be bent apart to step inside. (pic by ckp)

arrangement of the circuits

some notes

more notes

1,2,3 test…(3)

Sunday, June 26th, 2011

I found the time to go to Leipzig and use the [sublabs] oscilloscope on my [Diskokugel] circuit. Actually Nobody did that, assisted by Christian. It took a while to get it to work and the result was both satisfying and not satisfying. Because there was nothing to see. The crackle we hear when switching a speaker on and of did not show on the oscilloscope, which means the circuit works perfectly, and leaves us clueless as to the source of the problem. I did some more experiments but still have no idea.

Well, I might just leave it at that. Since the crackle is only really a problem when switching extremely fast or when a pure sine is used. I need to get this ball done now…

nothing to see here...

1,2,3 test…(2)

Tuesday, June 21st, 2011

I’ve been quite busy in the last weeks:

I presented my project at the [PD user group] in Berlin and got some interesting feedback. They would like to exhibit the Diskokugel or an installation based on it at the final party of this years [pd-con]. I feel honored but I have no idea if I can actually make it until then. Money is also an issue here. Having all the circuit boards made will cost…

I solved half of my clicking problem by getting the synchronization with the sound phase to work. Still, clicking occurs and since there was no oscilloscope at hand, I recorded it to make sure it’s not some kind of acoustic illusion due to differences in speaker loudness. The waveform clearly shows a distortion when the speaker is activated. When it’s turned off, something produces a sudden click and then the speaker swings out.

I will meet with Nobody and Christian (god praise his patience!) at the [sublab] this weekend and we will check the whole setup with an oscilloscope. I hope that we can fix this easily.

The noise occurring when a speaker is activated

When the speaker is turned of, something gives it an extra push.