The Solar 42F Drone Synth by Elta Music.

In this 42N Version, the LFOs have been supplemented with a switch that can be used to change the speed range of the speed control.
The cartridge slot also benefits from a simplified loading procedure.

Ambient Machine:
• Drone & Ambient Synthesizer
• analog sound generation
• 8 oscillator units
• 4 "Classic Solar 50" Drone Voices with photosensors [Drone 1/2/4/5]
• 2 Morphing Waveform Oscillators with Sub VCO [VCO A/B]
• 2 "Papa Srapa" Drone Voices [Drone 3/6]
• 10-channel stereo mixer with panorama
• Stereo effects processor
• Dual 12dB LP/BP Polivoks filters with distortion
• 2 noise generators
• 2 Sample & Hold generators
• 2 LFOs with variable waveform
• 5-step step sequencer
• Envelope follower
• Preamp for external audio signals
• Contact microphone
• Touch controller with 12 stripes
• Joystick controller
• incl. 13 FX cartridges, 5 patch cables, power supply unit

With the Solar 42N, Elta Music presents the successor to the highly acclaimed Solar 50 and thus the current premier class of drone synthesizers.
With its eight drone voices and oscillators, the Solar 42N combines three different approaches to sound generation and merges them into a complete work. The stereo signal path contains two Polivoks filters, which can be used to control the overtones of the incredibly dense oscillator mix, as well as a modulatable effects processor that is operated with cartridges. The touch controller is the central element for playing notes. Furthermore, there are a number of modulation sources such as the CV joystick or the 5-step step sequencer. All in all, the Solar 42N is an extremely versatile and interesting candidate for soundtracking modern sci-fi films, creating dark atmospheres for video games, capturing the morning fog musically over the first coffee in the conservatory and for everything that involves constant interaction between musician and instrument in the context of electronic music.

F vs N generation As far as modulation options are concerned, the Solar 42N has plenty to offer.
There are two LFOs with variable waveforms, two Sample & Hold generators, a 5-step step sequencer, an envelope follower, a Preamp with contact microphone (similar to Mutable Instruments Ears), the opulent touch controller with 12 stripes and a joystick controller.
The touch controller comes closest to a normal keyboard.
Everything else provides cyclical modulations, meandering sound shifts and a whole lot of life of its own, from mild to wild.
Each CV input can be modulated by one of these control voltage sources.
Everything that generates or requires a Gate or Clock can also be linked together in other ways.
Instead of driving the step sequencer with the pulser, it is driven by the envelope follower and the S&H is controlled by the Gate of the touch controller.

The modulation sources of the Solar 42N
The Classic Solar 50 oscillators
The four similarly constructed drone oscillator groups 1, 2, 4 and 5 with the strange dome each contain five tunable sawtooth oscillators.
Technically speaking, they are somewhat idiosyncratic, as they do not follow the logarithmic or linear voltage control of conventional VCOs.
The first and second oscillators are tuned low, the third medium, the fourth and fifth high. Depending on the control setting, there are also overlaps that create pulsating, choral clusters.
The mute switch can be used to deactivate each oscillator individually, creating different variations of chords and triads.

In addition, pitch modulation can be switched on for each oscillator, which is modulated via a photosensor (the dome) or a voltage generated in the Solar 42N.
The photosensor is influenced by the ambient light; it behaves differently in bright rooms than in a darkened studio.
The large buttons 1, 2, 4 and 5 are used to trigger the attack/release envelope of the drone group, which influences the level curve in the signal mixer.
HOLD can be activated instead of the envelope, in which case the activated individual oscillators are constantly audible at the corresponding mixer input. The Classic Solar 50 oscillators
The Papa Srapa oscillators

The two blue Drone Voices 3 and 6 are based on the DIY noise synthesizers of the Russian electro shaman Papa Srapa, who produced electronic devices with similar sounds in the early 2000s. These drone voices can be used to imitate sirens, bird cries, the sounds of space monsters and gunfire as well as surf and wind noises. The circuitry of this obscure "sound machine" is based on two Trigger-Schmidt oscillators that operate in completely different frequency ranges. White noise and setting options for FM and AM sounds are also part of the repertoire. The large buttons 3 and 6 are used to trigger the attack/release envelope of the drone group, which influences the level curve in the signal mixer. HOLD can be activated instead of the envelope so that the drone voices are constantly audible at the corresponding mixer input.
The Papa Srapa oscillators

The Morphing Waveform Oscillators
The green VCOs A and B are classic 1V/oct triangle-core oscillators based on the famous AS3340 VCO chip.
Both oscillators offer the basic waveforms sine, triangle, sawtooth and square, invertible sawtooth and sine to triangle morphing as well as a switchable sub-oscillator.
Pulse width modulation, linear or exponential FM and a wide tuning range give you everything you need to create "ordinary" oscillator sounds. The two oscillators are largely identical, VCO A has a hardsync input and VCO B a waveform output.
Both VCOs are primarily played via twelve touch controllers, which are also normalized to the ADSR envelopes. As with the other voices, the envelopes have a direct influence on the level curve in the signal mixer.
HOLD can be activated instead of the envelope, in which case the oscillators are constantly audible at the corresponding mixer input.
A morphing waveform oscillator
The backend - mixer, filters & effects
All signal sources, i.e. the eight oscillators and drone voices, the external audio input and the Preamp flow together in the audio mixer.
The volume and panorama of each channel can be adjusted.
This is followed by two Polivoks filters for the left and right sides. The filters work in either Lowpass or bandpass mode and have a common CV input for modulating the cutoff parameters; an adjustable distortion is the crowning glory of this charismatic duo.
Which signal source ends up in which filter is determined by the panorama control; in the middle position, the signal passes through both filters.
The last element in the signal path is the cartridge-powered stereo effects processor. The Solar 42N is supplied with 13 cartridges, each of which has three effect programs sorted by theme.
One of these effects can be selected for the left and right side.
Both sides are adjusted simultaneously with the X/Y/Z parameters, which can also be modulated via the control voltage, regardless of the effect selected. Finally, there is the Master Volume controller with headphone output.

Owner's manual