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Elka Synthex



elka synthex

elka synthex

audio demo trend price : 5000€
manual schematic demo video comments



Still ompressive analog polysynthesizer designed by Italian organ societies Elka & Orla.

Now Synthex reached the Olympus of all-time cult machine.

synthesizer Elka

left board

info KEYBOARD (weight: 30 Kg) 61 keys (no velocity) huge with black metal panel and nice wood sides; it originally came with a pair of legs attached on the sides.
The main panel offers no less than 36 knobs + 84 buttons + 6 levers, in addition a joystick for pitch bending and modulation.

Back panel terminal connectors: tape interface, sequencer sync, double jack outs, a pedal control for filter cutoff (upper, lower or both sound layer) and finally a set of 4 footswitch inputs:
1- program up
2- envelope hold
3- envelope release
4- glide control)

up to 8 voices polyphony based on subtractive synthesis generated by 4 overlaped boards featuring 2 voices on each of them.
The soundboards are multiplexed and manage different playmode voices combinations like DOUBLE MODE which layers 2 patches or even assigned to 2 different SPLIT modes.

edit OSCILLATORS there are 2 analog oscillators DCO per voice at octave range 16' 8' 4' 2' 1'.
A single DCO offers 4 possbile waveforms:
1. saw
2. pulse
3. square
4. triangle

5. noise: in addition it possible to add a white-pink noise generator to the mix.
Synthex oscillators structure features a detune knobs at 5 semitones range, a SYNC function for oscillators pitches and a digital ring modulator with fixed value.

PERFORMANCE special Polyphonic Portamento has a GLIDE option assignable to OSC1 or OSC2 (or both at same time) with adjustable speed rate.

filterFILTER is a multimode resonant model based on 8 * Curtis CEM 3320 chips. The VCF works in 3 different modes with possible polarity inversion option:
1. LP is the lowpass at 24dB/Oct slopes.
2. BP1 is bandPass at 12dB/Oct or BP2 at 6dB/Oct slope.
3. HP is highpass at 12dB/Oct.

The filter can be round and sweet or nasty.

lfo LFO section offer 2 modulators with a frequency range from 0.02 Hz to 20 Hz.
1. LFO1 offers 4 different waveforms (triangle, sawtooth, ramp and square) and modulates 6 destinations: pitch 1-2, osc width1-2, filter and amplitude, in addition the depth parameter can be set as well as a delay time.
2. LFO2 is simpler and directly triggered by the joystick: vertically it acts as a normal pitch bender while horizontally it changes the LFO amount sent to DCO or the VCF.

adsr ENVELOPE there are 2 envelope generator in total.
1. EG1 : 4 segments and defines the Filter VCF.
2. EG2 : same segments as EG1 and it is hardwired to amplitude.
Also 2 extra functions for envelope control: HOLD and SUSTAIN.

fx EFFECT a stereo mode circuit routes each voice to right or left channel, in addition a 3-modes analog chorus (which has fixed rate and depth values) brings a very lush touch to the sound, perfect for vintage strings or evolving pads! Hear by yourself a specific recording in the demo section.

edit SEQUENCER features a 4 tracks with 128 events each saved in non volatile-memory. Notes are recorded in real-time or step mode.
There are 5 recording functions buttons: Write, Beats, Delete, Loop, Ready-Reset + 2 knobs for gate EG (long or short envelope) and frequency rate.
Each track transmits Midi out signals and can be activated anytime with relative button, then, during playback, the whole sequence can be shifted in real-time for performance.

edit SYNC internal frequency or slave mode controlled by external +5V trigger pulses.


memroy MEMORY holds 40 ROM presets + 40 RAM slots user.
No external storage nor Midi dump as the only way to backup your library is the tape interface which is quite easy and reliable, just remember you have to access to tape mode switching the appropriate tab on the back panel.

midi MIDI second and third Synthex versions implement a basic Midi interface that manage only basoc note ON-OFF data. The internal Midi buffer is pretty basic, consequently the CPU easily chokes at big data flows... in such case, just switch the italian beast OFF / ON.

repair synthexMAINTENANCE definitely NOT the most reliable machine in the world: voice boards lifespan that is quite unpredictable! fortunately enough there are not so many custom IC onboard, Synthex is mainly build with common electrical parts "on the shelf" most of them still widely available on the market, but maintenance requires patience and experience since there are a LOT of circuits inside. Anyway you should not worry too much about this aspect on the future, just be friendly with you trusted technician.
schematic Get free schematics HERE.

picture by Gallioa picture of a Synthex overhauled personally by one of the original creator.

big elka synthex

lfo Production Series according to Castelfidardo center there were 1850 machines produced:

- wave 1: 50 units (no Midi)
- wave 2: 800 units (external Midi box)
- wave 3: 1000 units (standard Midi)


cat on synthex

*Laser Harp is the preset used by Jarre. More info about this controller HERE
**Drums Sequential DRUMTRAKS
***Delay by Dynacord Pdd14
**** acid line Roland Tb303 drums+ Roland Tr909 + Vocoder SCV350

cloud sound Soudcloud Synthex DEMO

beethoven cloud2 cloud1


Paul Wiffen & The Elka Synthex Synthex Demo Sounds Synthenoxe Part 1.0
Paul Wiffen Demo Sounds Synthenoxe Part 1.0

Elka SYNTHEX - My Sounds 1 - 20 Laser Harp sound by Elka Synthex ELKA Synthex & Roland CR-78
My Sounds 1 - 20 Laser Harp sound with Roland CR-78

italian synthesizer

german scan



german scan



synthex data sheet




music messe


scanning magazine


jarre synthex

laser harp
discover the LASER HARP




CHECK OUT Synthex prototype page featuring different voiceboards design.


UVI Vintage Legends features some SYNTHEX samples but also Yamaha CS-70-20-40, Chroma, Yamaha DX1, DK Synergy and K250. AUDIO DEMO



synthesizer Elka panel slider


-Massive polyphonic sound
- Sequencer


- technical care
- basic Midi
- High price



"The Elka Synthex is one of few analog polyphonic-structured synthesizer that boasts deep bass, rich strings and complex magical electronic sound"

The elka synthex board is for review, tips and questions. Please write only in english. Trading posts are allowed, but at your own risks!



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all snapshots*, sounds, texts copyright Polynominal.com / Eric Pochesci
* overhaul picture by Riccardo Gallio: thanks! also for some demos.

elka synthex 4.5 out of 5 based on 101 ratings. price €5000