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Jeanne 2012

16. May 2019

Between 2011 and 2013 I built up my biggest electrical construction, an instrument I called Jeanne 2012 (see more about the instrument in the Instruments section). I actually meant to build up the “Martenot waves” but they are unavailable – not only the instrument itself but also schemes – just nothing. I have seen them just once in my life. I did not dare to construct the instrument following the original conception since I am not acquainted with the vf technology and, above all, there is really no documentation available. Thus, I made it up as a synthesizer but with controls and functionalities of “Martenot waves”. The construction grew bigger bit by bit (First I constructed particular modules and tried to interconnect them, worked out once devised connections of historical origin – e.g. octavian) and then I started to devise it from the mechanical point of view. The first stage lasted a year, when I was just constructing the modules examining what is possible and how and figuring out how to arrange it all. Afterwards there was another year of the instrument construction – I did all the electronics during evenings and nights while focusing on mechanical things on days.

Here are a few pictures of the constructing phase (it is a fully-fledged analogue synthesizer with the Onde Martenot style controlling plus one more functionality, including LFO and the ring modulator and others). The instrument is actually constructed on the basis of MFOS modules that were developed by American designer Ray Wilson. The real analogue is irreplaceable in terms of sound – see the video in the video section.

The instrument chassis, a bit of joinery, the initial trial of keyboard:

Panels – it is aluminium, varnished, drawn with ethanol micro-markers following templates and over-varnished, simple technology, no offset :-))

Other fragments of instrument construction: mounted panels (the whole instrument has 135 control components, plus built-in tuner and a digital hall), the keyboard fitting (it is 6 octaves – it was made by cutting one Elka X705 manual into two and joining it with another manual, plus electronics around...) and the MIDI fitting in (the keyboard has the MIDI outlet to enable the Master keyboard along with internal sound).

A look at the hall fitting in (it is a “plundered“ Alesis Midiverb, a shortened panel, it sounds great, it was for next to nothing), tuners (they are again from “elsewhere“) and the MIDI module inwards the instrument. Furthermore, an overall look inside, still without a keyboard. A look at legs and pedals.

A look at the complete instrument...

And now the absolute ending, including a bit of speciality: I wanted to have a go at making a gong diffusor, an absolutely unique matter. The signal goes from the amplifier to the electromagnet which is through a small screw tied to an otherwise freely suspended gong. This is perhaps a bit strange “box” under the instrument. The sound is unbelievable and irreplaceable. In the video section you can find it at the end of Messiaen...

The development of gong difussor. I had no clue how to tackle that as there is no documentation of the original “Martenot waves” available – I just found some inspiration from a few photos on the internet. I used a 35-cm gong. Just a few months after the construction completion, I found out that Martenot himself used to use a 50-cm gong – I am just about to venture into it.

Hey, just if someone wanted to build it up themselves, this is the final scheme version :-)))

I also constructed a box for the instrument which is a bit like the original by Martenot, but this one is stereo – a well calculated bass reflex with passive correction traditionally made and very decent amps with FET – cheerful sound:

Then I made an alternative stereo tube box – it was constructed by cutting Hammond H100 into two and I was left a whole bottom – therefore the tube triamp and the speakers (15´a 2x8´). I made the case for it, which created a beautiful full-tube stereo combo playing decently classicly:





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