The synths and gear of Kraftwerk
By Glenn Folkvord

As one of several successfull synthesizer bands to come out from Germany, Kraftwerk has surrounded themselves with many myths and misunderstandings, and not always have they been interested in disavowing these rumours. One such myth is that they built all of their synthesizers and equipment themselves. While custom modifications and a few self-made inventions have occurred in their long career, most of their gear has been available off-the-shelf. Electronic Shadows has looked into Kling Klang Studio and dissected a selected range of Kraftwerk gear.
 
While the band used guitars, flutes, a vibraphone and other acoustic instruments on their first two albums, their 1973 album Ralf & Florian saw the use of electronics and keyboards extensively for the first time. Flutes and an 8-string guitar was also used, but the classic Minimoog synth was also used, as well as a Farfisa electric piano and an EMS Synthi AKS (pictured right). The latter is a portable version of the popular VCS3, with a small membrane keyboard, released in 1972, three years after the original VCS3 came out. One unique feature of this instrument is that that signal routing is not done by cables, but by placing small pins into slots in a patchbay grid, seen as a black square in the picture.

Guitar pedals
Kraftwerk’s keyboard and processing arsenal expanded for the next album, Autobahn (1974), their break-through album. In addition the the Minimoog and the Synthi A, they also used a white ARP Odyssey, a Farfisa piano, a customized Farfisa Rhythm Unit 10, and various processing equipment like Schulte Compact Phasing A and Vox Percussion King (below). The VPK is a guitar effect that looks like a miniature amp head. It is not a drum machine, but it has two circular pedals that you tap on to play the rhythm. You can also tap the rhythm on the finger buttons on the control panel of the unit. The King had ten sounds; crash cymbal, brush cymbal, bass drum, snare drum, drum roll, bongo I, bongo II, block, clave and castanets.

Another guitar pedal on Autobahn was the Mutron Biphase, a popular phaser pedal made by Musitronic in the mid 70s. It features 1 x 12 or 2 x 6 optical phaser with two sweep LFO sweep generators, resulting in square or triangle waveforms. You can also control each phaser manually, like a filter, with a pedal CV input.

Orchestron
The rest of the 70s did not see too many new synthesizers added, even though many other effects and processing units were used, such as the Roland RE-201 Space Echo, an Eventide FL-201 flanger, and other boxes. A Micromoog was added to their studio in 1977-78 and provided the bass sound for The Model on the album The Man Machine (1978). But more important was the Orchestron (below), in simple terms an analogue sampling device which used optical discs to store recorded sounds. Kraftwerk were given one of these long before it became commercially available. It was responsible for the choir sounds on Radio Activity (1975), which did not come from the famous Mellotron, a big keyboard instrument that many other artists used for choir sounds. The Orchestron also provided the choir sounds on the tracks Radioland, Franz Schubert and Showroom Dummies. The Orchestron goes back to the early 70s when the Optigan (OPTIcal orGAN) was developed by a subdivision of toymaker Mattel. It was different from other consumer organs of that time because the sounds were read off LP-sized celluloid discs which had graphic waveforms of real instruments and sounds printed on them. A unique concept in the early 70s, as it functioned as a primitive analogue sampler. But the Optigan lasted only a few years, and then Opsonar wanted to develop the technology into professional use. After initial development by Opsonar, Dave van Koevering (a former Moog employee) adopted the project and created the Orchestron, which he manufactured for two years in a variety of models, starting in 1976. The Orchestron was a more reliable instrument than it’s predecessor, but did not offer a substantially better sound quality, which is probably why it never became a big success. Only eight discs of sounds were made; Pipe organ, flute, violins, choir, hammond, french horn, cello, and saxophone. Kraftwerk later replaced their original Orchestron with a two-keyboard version which was used until 1981, when it was was replaced by a Moog Polymoog synthesizer.

Going digital
Getting into the 80s, Kraftwerk went digital. Their most digital-sounding album of the 80s, and only one of two albums of that decade, was Electric Café (1986). Their instruments on this album included some conventional models, such as the Linn LM-1 for kick and snare drum sounds, a NED Synclavier for processed voices and Emu Emulator for bass sounds. The LM-1 was Roger Linn’s first commercial drum machines. It was also the first programmable drum machine to offer sampled sounds. Twelve different sounds at 8 bits could be programmed in 100 different patterns either in realtime or steptime. The first 35 Linn “drum computers” were manufactured in Roger Linn’s home, but was later taken over by 360 Systems, which improved the quality of the unit. Roger Linn explains the trademark Linn sound in Mark Vail’s book Vintage Synthesizers: -I believe the LM-1 sounded better because I didn't incorporate strict textbook digital sampling theory. By the book, I should have filtered out any playback frequencies above the Nyquist frequency, which is a little less that one-half of the sampling frequency. I used a sampling rate of around 27kHz. However, filtering on playback would have made some of the drums sound pretty dull. Instead, I let some of the frequencies above that point get through, because the results, which can get distorted, sounded like the sizzle of drums anyway. Thanks to that decision, the LM-1 sounded better than some drum machines with the same sampling rate, because it had the highs. In a sense, I'm thankful that I wasn't very good at the engineering.

Doepfer
Kraftwerk took a long break in terms of studio albums between 1986 and 2003, but they toured several times in that period. Their kit for the 1998 world tour included synthesizers such as Nord Lead 2, Kawai K5000, Quasimidi QM-309 Rave-o-lution, a Doepfer A-100 modular synthesiser, Studio Electronics SE1, Waldorf Microwave, plus different sequencers, effects, processing and samplers. In the late 90s, Kraftwerk formed a tight relationship to Doepfer, especially regarding their sequencers and MIDI units. One of the Doepfer units Kraftwerk used in their 1998 tour was the Schaltwerk (pictured right), a high-end MIDI sequencer designed to create pattern-based musical structures. With all it’s functions available simultaneously, it is ideal for rhythmic patterns and arpeggios during improvisation and live events. Related is another Doepfer unit, the Regelwerk. It is somewhere between a MIDI controller and a sequencer, with 6 CV outputs for analogue synthesizers. It can generate MIDI data by means of 24 faders, each with two additional buttons and LEDs. With the faders you control parameters such as aftertouch, velocity and note on/off and nine other functions. The Regelwerk, designed as a hardware alternative to mouse-clicking in softwares, is also designed to easily create musical patterns, sequences and rhythmic structures and is ideal for live use.
 
Software based studio
For their first studio album in 17 years, Tour de France Soundtracks (2003) Kraftwerk approached music making an entirely different way than before. They have now digitized all their old tapes and sound sources, and invested in a virtual computer based studio. -We no longer have to deal with lots of cables and physical connections before we can work. The total-recall, power and portability aspects have convinced us completely to go virtual, says Kraftwerk member Fritz Hilpert. Tour de France Soundtracks was composed and recorded on a PC network with Cubase SX and a TC PowerCore soundcard (above) as the foundation. -PowerCore has played an important role in our production process, as it allowed us to run hi-end tools inside our native virtual setups, without clipping the CPU or having to get connected to our outboard gear all the time, Hilpert comments. For reverb on the album they used MegaReverg and ClassicVerb, both software effects from TC, plus a vintage Quantec Room Simulator hardware reverb. - We like MegaReverb’s natural sounding room impressions, especially for percussive material. It creates defined spaces rather than blurring the sound picture, Hilpert explains. He also used the TC Native Bundle’s dynamic processors and EQs, especially the DeX, during preproduction of the album, and when processing voices. Sound sources for the album includes the Steinberg Halion software synthesizer (pictured right).

Kraftwerk vocoders
A typical Kraftwerk album features vocals and lyrics processed by vocoders or, more recently, computers. Traditional hardware vocoders have been around since the mid 60s and grew in popularity in the 70s, but was originally invented by Homer Dudley (pictured right) in the mid-30s, when he worked at Bell Laboratories. The project he worked on was to reduce what we today would call bandwidth usage on their telephone lines. Modern vocoders, at least hardware ones, works by the principle of modulating the amplitude of a carrier signal (the synthesizer’s sound) to mirror that of the exciter signal (the human voice, fed into the vocoder through a microphone). The loudness of various frequencies in the exciter signal is analysed and the vocoder then adjusts the corresponding frequencies in the carrier signal, resulting in “robotic voices” which Kraftwerk used several times, for example on Die Stimme der Energie, The Robots, and Autobahn.
 
Kraftwerk’s vocoders include Doepfer A-129, MAM VF-11, Roland SVC-350 and VP-330, Sennheiser VSM-201 and EMS 2000 / 3000 / 5000 series. A NED (new England Digital) Synclavier (pictured right) provided synthesized voices on the tracks Electric Cafe and Music Non Stop (both 1986). The Synclavier is a very expensive digital sampling synthesizer aimed at professional sound designers. Even today, almost 25 years after it’s release, units may sell for up to 200 000 dollars (but basic used models going for around 5000 dollars). Kraftwerk probably used the 1984 model, with full sized keys with velocity and aftertouch, 64 voice polyphony, 32 MB of waveform RAM (expandable to 768), and digital recording of up to 16 tracks at 50kHz.

During the 80s and 90s, more and more computerized voices were used, in stead of vocoderized human voices. On the Computer World album (1981) computerized voices can be heard, coming mainly from the Texas Instruments Speak and Spell toy! It was introduced as a children’s learning aid in June 1978 and featured the first low-cost massproduced realistic electronic speech chip.

But robotic voices were so integral to Kraftwerk’s music that they were not satisfied with what they could find in the shops. In November 1990, the band patented the Robovox, a system and method for “synthesized singing in real time” controlled by MIDI. It was used to create a new type of computer voices for their compilation The Mix (1991), voices that could sing in a very human fashion.

For the recording of Tour de France Soundtracks in the early 00s, the band received a pre-release copy of the TC Helicon VoiceModeler software as the first artists in the world. It was used to create the whispery voices on Elektrokardiogramm, as software vocoders now were the tools used. Another software vocoder from TC, the D-Coder (based on an old Waldorf hardware vocoder) was also used, including for drum sound processing.

There you are, a little peek behind those metallic sounds from Düsseldorf, Germany.