Tag Archives: eurorack

Wob-Wob Fader

Wob-Wob Fader is simple CV-source controlled by fader. The feature here is that maximal voltage is reached in the middle position. This controller make it possible to easy perform sweeps widely used in modern music. similar technique is used with vinyl disks. This module has one Wob-fader and one fader with selectable mode.


UPDATE: Values of R2 and R3 can be changed to 4.7K to obtain more expressive sweep.

Creative Commons license
This circuit is published under Creative Commons «Attribution-NonCommercial-NoDerivs» 3.0 license.
Any use beyond this license must be discussed with author.

Low-Cost PSU

To feed modular system, you need bipolar power supply giving voltages from ±9v to ±18v depending from used system. Additional power lines might be needed. Eurorack standard suggests symmetrical ±12v line and additional +5v line which is useful for MCUs and some another digital ICs. It is possible to use computer power supply for modular systems, but PWM supplies have quite unstable voltage in fluctuating environment. Because of that, tune and volume of the synthesizer powered by PWM supply may have undesirable modulations. In some cases it can be used as artistic effect but to get completely predictable sound you need traditional power supply that uses a transformer.

Here is the example of such kind of supplies — Low-Cost PSU intended to work with external ±12v AC power adapter or external transformer.

The idea was to design power supply that is small, light, not so noisy, cheap and easy to build. This supply can be used as test supply in a lab or as a PSU for small, portable cabinet.

Schematics. The circuit is based on half-wave rectifier. AC splits in two lines and virtual ground with D1 and D2 diodes. The positive voltage is sustained by electrolytic capacitor C2 and ceramic capacitor C4, which is more fast. Then it goes to positive voltage regulator U2, followed by filtering capacitor C7, and protection diodes D3, D5. Minimal load and indication is provided with R2 resistor and D8 LED. The value of the resistor is to be selected manually to obtain comfortable brightness. I used 15K. The negative voltage bus is similar with different polarity and different regulator. The +5v bus is even simplier and utilize low-current regulator, 78L05.

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Low-Cost PSU: принципиальная схема

The Board. The whole circuit including heatsinks, seven 16-pin IDC-connectors and mounting holes, can fit on one 37×24 holes stripboard. Because of simplicity of the circuit, there is very few cuts and jumpers needed.

psu_low_cost_layout_stripboard

This is how it looks inside 3U rack chasis.
Low Cost PSU: фото

Creative Commons license
This circuit is published under Creative Commons «Attribution-NonCommercial-ShareAlike» 3.0 license.
Any use beyond this license must be discussed with author.

Regulated Bipolar PSU

To feed modular system, you need bipolar power supply giving voltages from ±9v to ±18v depending from used system. Additional power lines might be needed. Eurorack standard suggests symmetrical ±12v line and additional +5v line which is useful for MCUs and some another digital ICs. It is possible to use computer power supply for modular systems, but PWM supplies have quite unstable voltage in fluctuating environment. Because of that, tune and volume of the synthesizer powered by PWM supply may have undesirable modulations. In some cases it can be used as artistic effect but to get completely predictable sound you need traditional power supply that uses a transformer.

Here is the one supply of this kind — Regulated Bipolar PSU. It gives enough power for almost any system.

Voltage of the regulated power supply can be precisely set to obtain ideal symmetry for the oscillators, stable tune and low noise floor. This power supply consists of bridge rectifier, filter and three identical parts of voltage refulation, protection and indication circuitry. The positive line works as following: Bridge (D1, D3) rectifies AC, then it being filtered with two 3300uF capacitors (C1, C3) and 100n ceramic disk capacitor (C5) which are connected in parallel. Then goes LM317 regulator working as Adjustable regulator. (IC2, R2, R5, D8, C8) The load resistor (R8) and LED provide both indication and minimal load required for adjustment. The resistor value should be between 2K—10K, so it’s better to find LED which is not very bright.

The negative line works identical to positive with exception of LM337 used as regulator.

This circuit is very similar to Ken Stone’s solution. I believe, he was inspired by LM317 datasheet too.

psu_bipolar_schematic_v1.2

Version 1.2

Schematic
Component view
PCB Layout (mirrored)

BOM

Part Quantity Value Package
C1,C2,C3,C4 4 3300u 35v E7,5-18
C5,C6 2 100n 35v Ceramic C050-024X044
C7,C8,C9 3 10u 16v E2,5-5
D1-D13 13 1n4004 / 1n4002 DO41-10
IC1,IC2 2 LM317 317TS
IC3 1 LM337 337TS
J1,J2,J3,J4 4 Terminal block 2pos 5MM

(or 2pcs 4pos)

TERMINAL_BLOCK_2P_5
JP1 1 Header 2×8 pins 2X08
LED1 1 3mm Red LED LED3MM
LED2 1 3mm Yellow LED LED3MM
LED3 1 3mm Blue LED LED3MM
R1,R2,R3 3 10K Trimmer Bourns W3296 S64W
R4,R5,R6 3 1K 1/4W 1% 0207/10
R7 1 4K7 1/4W 1% 0207/10
R8,R9 2 10K 1/4W 1% 0207/10

Assembled unit (old version) looks like this:
Bipolar PSU: фото

Creative Commons license
This circuit is published under Creative Commons «Attribution-NonCommercial-ShareAlike» 3.0 license.
Any use beyond this license must be discussed with author.

Galilean Moons

galilean_moons_thumbhexinverter.net announced new Eurorack module, Galilean Moons.
Galilean Moons is a dual amplitude transmutator. It transmutates the amplitude of incoming signals through the use of voltage controlled envelopes and VCAs. It is designed primarily to create voltage controlled percussive sounds when fed with a sound source (in particular, its sister module, Jupiter Storm), but can be used for all sorts of other tasks in your modular system as well as to generate typical synth sounds.

– Two voltage controlled digital functions (envelopes), each normalised to their own low-distortion linear, DC-coupled voltage controlled amplifier
– Each envelope offers percussive attack/decay, attack/sustain/release or looping (LFO) mode
– Envelopes can each be linear or exponential
– Enables a new noise output, “XOR”, if plugged into a Jupiter Storm behind the panel. (everything besides the XOR output works with or without a Jupiter Storm!)
– VCA inputs are normalised to the newly-enabled XOR and main (“I”) output of Jupiter Storm when nothing else is plugged in
– The envelopes and VCAs can be fully utilised elsewhere in your system by plugging into the corresponding function’s jacks
– Perfect for synthesizing voltage controlled percussion and other effects!

Module width: 18HP
Current consume: 88/65mA
Depth: 30mm

ACXSynth MIDI2CV Firmware v5.4

New version of alternative firmware for ACXSynth MIDI2CV has been released..

Changes:

1. Added full support for legato play in Mono and Poly1 modes
2. D2 key toggles legato retrigger
3. E2 key toggles velocity curve in Mono mode (Linear/exponential)
4. Trigger duration is extended to 1.28 ms.

New version can be downloaded on the Project page

hexinverter.net ACXSynth MIDI2CV polyphonic MIDI-CV converter

MIDI2CV_ThumbCanadian company, hexinverter.net Electronics makes various modules for analog synthesizers. Almost every project is cross-platform and designed not only for Eurorack but also for 4U/5U formats. The model range includes noise-generating modules, sequencers, percussion, envelope generators and effects. This summer Hexinverter has released a new model: 4-voice polyphonic MIDI-CV converter.

MIDI-CV converter 5U module was designed by Alain Coupel of ACXSynth. In the year 2013 Stacy Gaudreau started to make his own version for Eurorack. Finally project became nice 8hp wide DIY module. Later I took a part in developing too by making new firmware.

Full kit (PCBs, components, front-panel and hardware) costs $120. (it’s not perfectly clear, USD or CAD, but rates are very close)

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Полумодульный синтезатор Pittsburgh Modular Cell [48] System 1

System-1-Main-ViewАмериканская компания Pittsburgh Modular имеет в своём арсенале несколько десятков модулей, поэтому они могут предложить несколько готовых Prewired-систем, заточенных под разные задачи. Одной из серий таких систем является Cell [48], основанная на одноимённом кейсе на 48 посадочных мест. Далее речь пойдёт о первой такой системе, представляющей собой управляемый по MIDI базовый одноголосный синтезатор.

Cell [48] System 1 — это готовый синтезатор, который может послужить отличным отправным пунктом в мир модульного синтеза. В качестве главного компонента используется модуль Synthesizer Block. С этим модулем постоянно соединены несколько интерфейсных модулей, за счёт чего синтезатор полностью готов к работе без единого воткнутого кабеля (не считая, конечно, MIDI или CV/Gate и аудио-выходов). При этом каждый основной компонент системы может быть соединён с другими компонентами этой или другой системы.

В базовом виде, система Cell [48] System 1 предоставляет широкую выборку традиционных тембров аналогового синтезатора: жирные басы и тёплые лиды создаются несколькими поворотами ручек. Использование соединительных патч-кордов позволяет экспериментировать с модулем, предоставляя широкие возможности по модуляции параметров одних компонентов сигналом с других компонентов.

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Gijs Gieskes

Сегодня я коротко хочу рассказать об одном интересном дизайнере из Нидерландов, который вносит серьёзное разнообразие в мир Eurorack модулей. Я точно не знаю, как правильно должно звучать его имя, но я буду называть его Гийсом Гискесом. Он делает электроакустические модули с нарочитым отсутствием гламура. Надо признать, что он разрабатывает модели с сумасшедшей скоростью, да и разнообразие его идей поражает. В формате Eurorack, в модулях с панелями из прозрачного оргстекла и текстолита могут быть помещены самые разные предметы или их части, параметры работы которых могут управляться с помощью CV: метроном, жёсткий диск, динамики, радиоприёмник, вентиляторы и другие предметы. Гискес разрабатывает и чисто электронные приборы, для которых он даже публикует схемы, но его «фишкой» является именно электроакустическая серия модулей.

Пример самоделки Гискеса: жёсткий диск с аналоговым управлением

А вот, например, Clock генератор из метронома с пьезо-звукоснимателем

Множество подобного добра со схемами или на продажу вы найдёте на официальном сайте Гийса. Ссылка на его сайт также есть в нашем разделе ссылок.

Flame Arpeggiator 2013

На MatrixSynth пользователь со смешним ником Ebotronix выложил видео с демо-композицией относительно нового цифрового арпеджиатора фирмы Flame, известной по модулю Talking Synth. В демо перепробованы все возможные режимы.

К сожалению, пока непонятно, где можно купить этот модуль.