Hacking a Discman into a glitch machine!

A while ago I came across a female hacker/circuit bender under the name r20029 who managed to turn an obsolete Sony Discman into a crispy glitch machine! She baptised it the 'Sony Discbitch' :-)
I managed to hack my own CD player. Here's what it sounds like:

What the hack does is getting access to the anti-skip IC which stores a couple of seconds of audio on a RAM chip. The position of this chip varies from player to player so look up the name of the chip until you find the anti-skip IC. The pins A0 through A9 are DRAM adress pins. If we connect these pins together, we can confuse the machine to get glitchy playback and weird artifacts and noise.

After damaging a couple of CD players I finally managed to solder wires onto the tiny surface mount pins. Hot glue is your friend to make sure you don't accidently pull the wires off the pins when you've soldered it all together.

I think this mod holds great potential for a future module for my modular setup. Maybe have a couple of sample CD's with different material suited for glitchifying.

DIY Modular #1: Wooden case and CRT-monitors.

Hola amigos y amigas! :-) Besides enjoying a long summer holiday, before starting on my master's degree in electronic music, I've been rethinking my entire setup and decided to abandon the idea of having lots of separate boxes which I have to arrange and connect for every concert and instead jump on the modular wagon but with my own standards and designs. (no "eurocrack" ;-P ) I am going to design and build every module from scratch and include some different and unique modules and parts and try different methods of circuit designing. The frontplates are going to be transparent so all the insides are visible, which adds an extra dimension the the machine - it will be an work of art, from circuit to interface.

I wanted something organic and easy to work with so I went with wooden frames for the cases and for the front- and backplates I chose transparent acrylic glass as it's neat to be able to see the insides of the machine. I will put a lot of emphasis on the aesthetics of the circuits, parts and components because of this. For attaching the acrylic frontplates I am going to use an alu-rail with rectangular 'slide nuts' as the width of the modules will vary.
In the future I want to be able to expand with further identical cases on top so I added a mechanism for attaching the frames to each other. The drawing above shows my vision of what the machine will ultimately end up looking like.

Some snaps of the cases / frames:

Wooden frames with plexi back plate

Single frame / case

Both frames attached

I found it crucial to start with the design of the power supply part. I had an old PSU from a laptop lying around - 19V DC with app. 5A of juice to play around with. Some of the parts will be quite power-hungry so in the future I might have to step it up to 10A. I found a cute old capacitor from Denmark and decided to use it as stabilizing cap. My plan is to have most of the modules run on  ±12V but I might add a 5V line as well but so far I've been using LM317 variable voltage regulators for each device.

Power connector and switch w/ LED

Rear view - large capacitor added

Personal notes on PSU

The first actual modules will be a 'terminal' with a green-monochrome CRT TV. It will receive a video signal from an Atmega328 generating simple text strings with data such as the temperature inside the box, total run time, date and time and a lot of other stuff.
Next to it another CRT TV of the same size will display the master stereo output as a simple oscilloscope. Beneath the TV I will install two analog VU meters with a nice warm backlight as well.

Shelf for the TV's and front plate test	Side view of the shelf	Rear view of the CRTs
Both TVs turned on!	VU meters on as well. :-)	Startup-text generated by the arduino

An analog current panel meter will be beneath the terminal showing the power usage for alle the modules. Each TV draws around 1000 mA but so far 5A in total should be enough. I've used 7812 regulators for each TV to supply 12V but the regulators turn very very hot and will shut off without proper cooling so I had to mount rather large heatsinks.
The plan is to mount front plates in front of the TV's and have all the knobs and in/outputs controlling the TV and the terminal.

For labels I want every front plate etched with a CNC router (or just by hand?) and then edge-light it with an LED-strip installed beneath the acrylic. A test looks like this (scrap acrylic with scratches):

LED-strip test

Edge-lighting test

Edge-lighting test

Snaps from The Lab 2015

I now have 3 months vacation after finishing my last exam so I thought I would show you some of the more recent additions to the studio / lab. :-)

Tascam Portastudio 244 (4-track)	Various CRT-TVs for future projects	Old school oscillators
Modding a guitar with pickups etc.	Wooden frame for modular synth	Sequencer board for Aristoteles
4-track Reel2Reel	Original Gameboy with LSDJ Tracker	Monochrome monitors
Thrift shop findings!	Donations from a physics teacher	Double-bass (gift from a friend)
Univox LEM Tape Echo	Univox LEM Tape Echo	Retro cassette player without case

Debut album released on DIY audio player

For my bachelor-degree project I decided to pile together various recordings and compostions collected during the past years I've been under my alias Dögenigt and make an album.

For a long time I'd been thinking of an alternative to the digital release or vinyl and what have you and I discovered a tiny circuit based on a miniature arduino-like chip (ATtiny85) which can be programmed to read lossless quality sound files from an SD-card and play them (in 44.1 kHz 16 bit) via the PWM pins.
So I decided to go ahead and build the circuit into a small audio player to be built into some casing as my album and have the project and journal revolve around that.

I've been working on the project for the past couple of weeks - it's all in the papers I wrote.
Link to the paper in danish: http://data.xn--dgenigt-q1a.dk/DIEM/opgaver/BA3-Bachelorprojekt.pdf
I tried to translate into english but failed to do so. Let me know if you have success!

Images from the project:

Wave-player based on ChaN's circuit and code:
Runs of 3.3V and outputs sound directly to jack output in 44.1 kHz 16-bit sound. So far, only mono as more digital pins are needed. The PWM-outputs on the ATtiny85 each create an 8-bit signal, when 2 are added together they make 16-bit. For stereo 16-bit sound 4 digital pins are needed. We didn't have enough time to do this but I know of a guy who did it with an ATmega328.

    Finalized player with batterypack, speaker and SD-card.

 

    Simple version of the player with no jack output but screw terminals instead for power and output.

    Player cased inside VHS-cassette :-)

    ChaN's (simple!) circuit

The album is already online on my bandcamp as digital download but in the future I will have the release available on this platform as in the pictures above. The whole album can be bought for $10 and of course streamed for free. All the tracks are made with my homemade gear. Enjoy!

Composing music on the Gameboy with LSDJ

I've been busy with my undergraduate project on the conservatory but I've been spending my time fiddling with the LSDJ (Little Sound DJ) for Gameboy Classic / DMG - really fun and inspiring way to compose music! You've only got 4 channels to play with: 2 pulse oscillator channels, a wave/sample channel and a noise channel.

I enjoy making pseudo-covers with trackers so here's my first gameboy-track inspired by Xanthochroid's "Bipartisan Apostasy" Dimmu Borgir style ;-)

Dögenigt @ Mayhem: Noise Convention #1, 18/10/2014

I just received this footage from the Noise Convention last year on Mayhem, Copenhagen. The video is not very long but there's audio recording from the mixer of the full concert if anyone's interested.

Roberta the Robot v0.1 (voice recognition test)

I want to show you a cute little side-project I am currently brewing on. It's going to be a robot with a

voice recognition shield for Arduino (EasyVR 2.0 Shield). The idea is to have a fully functioning voice controlled robot able to control power relays with motion tracking servo motors for the neck and arms.
Right now I am testing the voice recognition out with responds in both english and danish.

The final idea is shown in the drawing to the right. There will be a lot of challenges involved if I am going to realize all the ideas. I will need a little help from my friends.

DIEM Analog Synth Workshop 2015

Just a few shots from this weeks analog synth workshop with Henrik Munch on DIEM.

Henrik explaining the VCO	Random CV from  S/H module	The Roland System-100M
Close up of the System 100M	Syncing tempo with drum machine	The iconic TB-303
Moogerfoogers	Learning to use Oberheim Xpander	Jamming with the gear

Aristoteles Logic Synth Update #5: Sequencer

I couldn't hold myself back after finishing the AND-gate module for dear Aristoteles so I dug up the schematic I drew for the 10-step sequencer module and jumped right in. In the video below I'll demonstrate how it works and the possibilities are vast! Combined with the AND-gates it's very convenient for creating melodies and patterns.

The sequencer is based on the '4017 CMOS Decade Counter' which counts from 0 to 9; adding 1 every time a clock pulse is received on the CLK input. It has 10 outputs going high/low one at a time depending on the current count. Only one output at a time can be high; the one corresponding to the count.
There's a reset pin which decides when the counter will reset to 0 so it's possible to have it count to any number below 9. I've implemented a rotary switch for setting the count from 9 to 0. If the reset pin is set to ground, the count limit will be set to 9 (default).

If an audio range signal is sent to the clock pin and one listens to one of the outputs, you get harmonic intervals when reducing the count limit. This makes sense as it only takes half the time to count to 5 instead of 10.
The frequency ratio to the frequency we get when counting to 10 (which can be seen as our fundamental) can be calculated by dividing 10 with the desired count. So the relation between i.e. 10 and 5 (10/5) is 2. We multiply our fundamental with this number to calculate the interval, which in this case would be an octave.
The chart below shows the intervals we get when we're adding the value of the fundamental - which is what happens every time we add a step for the counter. Interesting stuff!

Multiple of fundamental	Ratio within octave	Common name	Hz and chroma (Example)
1x	1/1	Fundamental	110 (A2)
2x	2/1	Octave	220 (A3)
3x	3/2	Perfect Fifth	330 (E4)
4x	4/2	Octave	440 (A4)
5x	5/4	Major Third	550 (C♯5)
6x	6/4	Perfect Fifth	660 (E5)
7x	7/4	Harmonic Seventh	770 (G5)
8x	8/4	Octave	880 (A5)
9x	9/8	Major Second	990 (B5)
10x	10/8	Major Third	1100 (C♯6)

As is the custom, I've attached the scheme for the circuit for this module. It's not that intricate, just LED's and output jacks on each output. I see that I forgot to add the transistor LED-drivers, but it's just as usual - look in the schematics for the other Aristoteles modules to see how they should be wired.
I've used a 12 position rotary switch for the reset switch, I couldn't find any 10-pos so 2 of the positions are grounded which just sets the count limit to 9 (all 10 steps). It can be tricky to find out which pins correspond to the switch positions but easy enough when using a multimeter for testing continuity between the output and the desired pin.

I will post all my stripboard layouts in a single package when I am finished with the last module :-)

 UPDATE 7/2-15:

My brother and I (as the duo SNU) had a really nice jam with the Aristoteles modules so far.  Here's a video of  our session when the sequencer was still on breadboard. I had my Clock Box (which also runs on 40106 and 4040 oscillators) control the power for the 4017 so a lot of modulations back and forth.

Aristoteles Logic Synth Update #4: Logic Gates

I thought it was time for building the next module for dear Aristoteles, my 'lo-fi logic synth project' so I did the logic gate module which consists of 8 AND gates with 2 inputs and an LED for the output. The truth table on the right describes how the gate will behave: the output only goes high (1) when both inputs are high. The result is a very simple form of amplitude modulation, or it can be used to control the path of signals from the other modules with counters or LFO's, you name it.  The video below speaks for itself.

In the video I demonstrate the effect of the 3 different frequency ranges on the oscillators: LFO range signals are good for 'letting through' audio range signals at a certain rate for "beep beep beep beep" sounds. 2 audio range signals will generate complex pulsating modulations and beatings when adjusting the pulse width.
Setting the range to the high pitched setting on both oscillators will generate classic vintage radio-like modulation squeeks. I also tried using the 'octave divider module' for one of the inputs which has its own unique sound.

I chose to have all the logic gates as AND gates. For a long time I was in doubt about wether to have a pair of XOR or NAND gates just for the hell of it but I could not find a good reason as they don't do much sound-wise where as the AND gate is so clear in its function and I want to be able to make complex signal paths with counters, dividers, random clocks and all eight oscs - all controlling each other through the gates. 

I am already starting on the 10-step counter 'cause I cannot wait to have each step 'open' a unique oscillator with different frequencies!

The circuit is very simple, I basically just wired the in- and outputs straight to the 4081 but attached 100K resistors on each pin to prevent static electricity from the end of the wires going into the chip when patching.
LED's are controlled by transistors as always to prevent voltage dropping on the outputs.

UPDATE:
I had my brother a.k.a. SNU over and he fell in love with the new module which resulted in hours of wiggling.
Here's a a little peak of the tweak :-)