The Mutant Yamaha PSS 2800 MK 2 ///

After one decade in circuit bending experience and a long way to run, it turned out, that I have to do more projects. This year was stranger, than all the other years before, because I established a new workshop, which was flooded two times. I got almost struck by lightning in May and had to overcome main issues in the planning, because it takes always more time, to do the whole job. One whole year went by, to finish this big and robust device. All the sanding was done by hand as always and took more than 16 hours. The wood which I used, came from an cupboard door and my old improved shelf, in my old window. I can't tell all the struggles and strange things I've seen in this time, because no one would believe me. But I'm like a machine, and I would go through walls to make everything possible. So I took off and headed to new fields. I thought, why is this thing so static? I wanted to change the way, my devices would look and they should have more possibilities to alter the sound, like big synthesizers. I spend the nights in front of sketchbooks, turned everything around and saw so many enlightened moments and new ways. This machine turned out to be a turning point in the whole series. I invented new ways to turn the almost simple nature of this seemingly toy keyboards to a new level. I started a band and built enough machines, to get everything to work. We drove around to several places and it was barely planned, but in the end, everything turned out to be right, by accident. A camera team followed us, to document the whole action. I finished this machine in the last hour, to get on to the gig. The stress was a true horror, like I nearly died this year, again and it emerged in one weekend with kind people and a concert, which wasn't seen before. At first, I thought, we are on a performance festival and should perform the post modern noise of this century. But in the end, we were supposed the big bang of art in the whole show. The camera team invited me to give an interview and I wasn't fine with that, but took the chance to say something about it. The whole concert had another background in three dimensions and nobody at the event knew about it. There were shocked faces, and I would like to say, that nobody, who joined the audience that day will ever forget this. All the details will be revealed later, but I can say, that we are hunting sounds. I would like to say thank you, to my band members, who made this possible, without any hesitating moment. The documentation will be released later this year, I hope. The whole setup of this machine was done in a modular way. Nearly every function is able to modulate other modules on the front panel. When we drove to the first gig, nothing inside was finished, but empty. Only the bend points were connected. All the circuit boards went in, during the next month, afterwards. One night before the gig, we walked to an seemingly abandoned place in the face of nowhere. There were hundreds of bats wo hunted insects under the streetlights, and I thought, I'm at the right place to stay.


The so called Atari Punk Console is a popular circuit that uses two 555 Timer Chips or a single 556 dual timer IC. The original circuit, called a "Sound Synthesizer", was published in a Radio Shack booklet: "Engineer's Notebook: Integrated Circuit Applications" in 1980 and later called "Stepped Tone Generator" in "Engineer's Mini-Notebook - 555 Circuits" by it's original designer, Forrest M. Mims III (Siliconcepts, 1984). But the Kaustic Machines Crew named it "Atari Punk Console", because of it's LoFi sounds, which resemble the old Atari noises, from the early video game history.

The Robot Moon 393

Nearly three years ago, a friend of mine gave me a MAM Freebass FB-383 - TB-303 clone analog bass synth. It was a rack version of the famous TB 303 by Roland, lacking the programming features. And he said, he got it from another guy, who abandoned it as useless, and he couldn't work with it, because the front panel was almost unreadable. The lettering on the front Panel, which was brushed aluminium, was done in a nearly neon orange. He only asked me, to change that and to build a new casing for it, which faces up to the actual user. I took the challenge and tried to find bend points on the circuit board, but had no luck. In the end, I was afraid of burning it and so it took six months from start to finish. When you play notes on an external keyboard, the tones tend to fade away. There was one point, when I discovered a fake hold, on the board. This was the breakthrough. And in the end, I called it he "Robot Moon 393". I should have added one or two LFO's, but I wasn't ready for this, at this time. But it turned out, to be the craziest 303 on the planet.

The Yamaha PSS 2900 MK4

This is instrument is really special, because I pulled it out of a pile of junk, under lot of wires and computer parts. One key was broken. The problem is, that I don't use instruments, which are not in a acceptable state and a broken key is enough for me to keep it for over six years. So it gathered dust over time. But I needed it for the PSS line. We wanted to play a gig and I had to build four machines to do the show. So I want online and found a broken Yamaha PSS 480. The seller said, that there is only noise, which comes out of it. I fixed the problem in a matter of minutes and there was only one loose solder connection and dust inside of it. Bridging dust ist a main problem in many old electronic devices., which were manufactured twenty years in the past and before. The usability of this instrument was a mess and the interface was such horror, that I decided to take it apart. I can't keep everything, but the parts. I took the main machine apart and scrubbed it, until it was like almost brand new. The keyboard was in a good condition and used to fit. And here it is, the Alice Edition, dedicated to a friend of mine.

The Yamaha PSS 2900 MK3

Back in 2009 I released a small EP with six songs. A friend of mine joined us two days before christmas and gave me exactly this Device. It was the first synthesizer in my life. You would say, this was late. Yes, but not too late I think. Then my obsession startet to get real. I tried to bend it two times, but it was a real mess, because no one of the modifications seem to work properly. So I changed everything back to its default state. 

After six years passed by, I tried it another time and made my first prototype for the PSS series. Because it was more than sketchy, I decided to give it a proper look and some of the new functionalities of the later models. Through these modifications, it tends to behave in another way, than in its prior state and I have to say, that it is not about the look, but functionality. 



Once again, it took me nearly half way, through the galaxy and back. It was completed after 160 hours of work and there are 25 m of wire inside of it. It’s a heavily bent Atari Punk Console in my own suitcase design. The whole story began with a small keyboard, which was a gift, from a friend. The power button was broken off, hanging on the rest of some plastic casing and it's wires. I took it through the city, in the middle of the night. It was snowing and I ended up, in a spontaneous snowball fight, with strangers. It was fun, but I slipped and the whole keyboard broke apart in two pieces, when I fell to the ground. But I kept the broken unit in a box and needed it for the speaker holding, to finish this project. The clue is, that the speaker on the back has a backlight and is entirely rebuild with wood and the cap piece from a bottle of wiper. Because the original speaker had different measurements, than the original, 4 Ohm speakers, but I needed an 8 Ohm speaker for it, to work properly. When I tried to assemble the case, there where two screw nuts, which I didn't had. But there is always a way and I drove to a scrap metal container. It was empty, but I climbed in, because there where some screws and screw nuts on the ground. And what a surprise. Two screw nuts, out of seven, which I found inside, had the right diameters. Jackpot!!! The orange cable chamber, on the back, came from the handle of an ironing board. The other orange plastic parts are from of a toy laser gun and the roll of insulating tape. I salvaged the eyes for the space invader, on the top panel, from an ugly sixties lamp, which came out of a pile of trash on the street. The wooden side-panels are made from an old shelf.This time, I had to make my own circuit boards, but it worked well. When the oscillator board made it's first noises, I tried to find different ways, to control the oscillators. I added one square wave “LFO” –  one 8 step sequencer –  routable to chip A and B. The keyboard design is dedicated to the arcade button style on the old cabinets. You can also transpose the sequence with the keyboard. Nearly every function on the front-panels are switchable to light control. The Ghost Hold function is a Key, under the real keyboard. Because the circuit is a mono synthesizer, you couldn't press the lowest key, if it would be solved, in this way. So this is one extra key and a hold function, across the whole keyboard. You can hold the key you like, with a 12 position rotary switch. Every step, on the 8 Bit Sequencer can be switched off, to alter the according sequence. The Keyboard can be switched to light control, as well, as the tuning of the two chips. You can control the pitch, the HP Filter, as well as the LP Filter, with the LFO. The main speed, of the LFO and the step sequencer, are also switchable, to light control. This mean machine, is a real beast and some adjustments, may lead to confusion, but I had to built it this way.

This little guy came out of a trash mountain and was stuck under some smashed laptops and a bunch of cables. I took it with me and gave this buddy a few days to dry.

I was surprised. Sometimes I can’t understand, why somebody would throw it away.

The main problem with these units was the power connector on the back. After a while, it gets wobbly and the unit starts to break down for no reason. Another problem is the power supply. It has to have 12 Volts with 2000 mA. These instruments used to break down during the operation, if they were underpowered. This Synthesizer had a broken Main Switch. You couldn’t change the operation to one hand and so on. So I went down in the basement and pulled a similar contact switch out of a dead Hohner Organ. The measurements were not the same, so I had to cut the iron feather in half, soldered the two contacts together and melted them into the original plastic holding. Hell Yeah, it worked and the rest is unknown history. The PSS 290 and the PSS 280 have the same board. But I noticed one jumper cable on the board, which seemed to be out of place.

THE PSS 2800 MK1

My first Synthesizer or Keyboard was a Yamaha PSS 290. A friend gave it to me in 2010 – thank you very much Karl. My first two Bends on this Keyboard were a true horror. I found a hidden distortion, but every sound used to end in a clipping. So I pulled them out again. But one year later, I tried to bend it again and I had more experience. In the end, I found so much interesting bends and tested it via the first prototype. They are not harmful to the engine. And a big respect goes out to Yamaha, because this machine never hangs up. If you think the unit broke down or crashed, you are wrong. All you have to do is …. pressing some of the keys or adding some more patch-cables. And the Ghost in the Machine will come back. This build was planned as a giveaway for an artist. After two prototypes, I moved the machine to a new level. And it went to London, to “Look Mum No Computer”. May the “Ghost in the Machine” be with you!

Demo // Youtube: "Look Mum No Computer"

Show More


It’s a small suitcase Synthesizer with one “Crazy LFO” – one Bitcrusher – one programmable 8 step sequencer – and the “Robot Guru Spot” to crash the device in different ways. And sometimes, the Guru is meditating. The whole unit was built out of trash wood, which should be burned. One month ago, I added a Synch-Mod to enable two of these little synths, to talk to each other. This little buddy came out of a pile of trash and some lights broke down. The reason for this was a broken connector inside. I fixed it and it works wonderful.

Show More


This small device is a prototype for the Terrormin MK3. It has one “Simple LFO” – one Bitcrusher – The machine was also built out of trash wood. You have various random controls for the pitch and a hold function for the tone itself. The antennas are touch sensitive and you are able to play around with it, like on a normal Theremin. But it is quite different, especially the behavior of the machine. The base section holds some controls for the light sensitivity, volume, the LFO and the robot voice. There will be another one, but this will take some time on the drawing board, of the lab.

Show More


My second Bend was a small unlabeled keyboard toy. I could pitch it and one day it died. But I kept the parts in a box as usual. I had this idea of two voices in one box. So I took two smoke detectors, build this box and salvaged the keyboard unit. The keyboard is touch sensitive and changes the tone right before you could push a key. In the center of the panel you have a tune knob for the right pitch. Yes it is only a noise machine, but it has some points, to explore the capabilities of the sound. And like always, nearly everything was build from parts, which I found on the street or in the trash bin.

Show More


One night, a friend asked me, if I could build a Theremin and yes, it was possible, but in another way ….  after this conversation, on the way home from the party, I found a smashed Ghetto Blaster and I took it with me. I realized it with an old cigar box and some parts from old furnitures. I didn’t have the parts for any circuit, so I used a smoke detector for the voice …. it worked fine …. during all test-sessions …. and it became a very strange machine ….

Show More


It was a Casio MA 130 and it’s finished  …. and there are still more things to do!” It became a real monster …. and now it’s a Space Machine …. ! It has a low filter and a high filter, which I found on the main circuit and a hidden distortion. There are two smoke detectors inside, which could trigger one note each. But the trigger time wont change, because I didn’t know, how to do it otherwise at the time. Behind the instrument is a hidden Random Trigger, which reacts to light like a Geiger Counter and matches every beat. Above this section is the Robotron Step, which is able to sequence 8 Steps like a traditional sequencer and you are able to add more steps to the according sequence. The next block houses one Bitcrusher and a simple Delay unit, which are patchable. The last thing to do is to fix the delay unit, but I know, why it isn’t working properly …. but everything step by step …. I think this old buddy has to be redone in a more actual style, because it is also a prototype unit, to test new ideas ....

THE PSS 2900 MK2

This Machine is the second version of the Yamaha PSS 2900 and it came from the trash. The machine was the most abused one in my collection and saw much better times. I had to remove everything, because there was water inside, spiders, much dirt and corrosion. On the downside, the case was cracked open and some of the screws for the housing were broken out. I decided to make new side-panels, to cover the broken edges. It looks used in a nice way and works fine ....



  • Grey Facebook Icon
  • Grey Tumblr Icon
  • Grey Instagram Icon

Lennestraße 1 | 19053 Schwerin | Germany

This site was designed with the
website builder. Create your website today.
Start Now