ST-Modular Envelope & Slopes, New DIY Feature-Rich Modulator Modules

ST-Modular is expanding its DIY module range with two new modulators: Envelope is feature-rich ADSR/AR envelope generator & Slopes a sequenced quad slope generator.

The Eurorack adventure can quickly become expensive. Two oscillators, filters, envelopes, LFO, a case, quickly increase the bill. However, if you build the modules yourself, you can save a lot. Soldering experience is a prerequisite for this. There is a huge DIY community and many Eurorack modules are available as a DIY project. As a PCB only set or in a complete kit.

One of the stars of the DIY scene is currently Stefan Tretau from ST-Modular. In the past few months, he showed very interestingly, deep modules that are only available as DIY projects. For example, Oberhausen is a complex oscillator module with many shaping options and one of the big products from Stefan. Today he showed two more modules, this time two sophisticated modulator modules.

ST-Modular Envelope

Envelope is a classic 12HP ADSR/AR envelope generator with advanced control and shape functions. The module has four sliders, one for each stage for the length that is also controllable via CV. Each CV input has a dedicated attenuator for precisely adjusting the CV amount. Then, there are dedicated shape potentiometers for the attack, decay, and release stages. With these, you can switch from exponential to logarithmic response curves.

With the RF CV input, you can control all rising and falling stages at ones. Pretty handy functionality. A loop function is also onboard. Thus the module can generate modulations like an LFO and controllable via the mod rate knob. The Envelope module also features an internal gate and modulation source. It allows you to internally apply a triangle/square wave LFO to any stage when nothing is patched to the CV inputs and the attenuators are turned clockwise. It has an envelope out (env out) as well as an inverted output (env inv).

Further, it includes an internal VCA routed to the envelope output. This gives you quickly an envelope-controlled signal available at the VCA out jack. A nice feature-rich envelope generator with many useful functions, and a nice layout.

ST-Modular Slopes

Slopes is a quad slope generator with an integrated gate divider that can simultaneously generate 8 control voltages. You can adjust them using the rise knobs and fall sliders. Each slope can be triggered with a trigger or gate signal and outputs a voltage from 0 to +10V and on the inverted outs respectively -10V. Lower voltages are available via the attenuator on each slope.

Shape 1/2 and shape 3/4 potentiometers let you add an additional triangle LFO to the two signals which can be controlled using the rate knob. The latter also changes the rate of the internal gate, which is divided by 2, 4, 8, and 16 and fed to the four slope gate inputs (from left to right). You can break it with an external gate/trigger signal.

Slopes also as a sync function (CLK input) with which you can synchronize the slopes to external modules. This overrides the internal gate generators and feeds the gate divider to trigger the four edges according to its division. The RST/Dir input resets either the gate divider or changes its direction.

The module has four outputs (1/2 & 3/4) which provide a mix of slopes (1 & 2) and (3 & 4). You can change the mix by inserting an inverted signal of one slopte with the 1 INV or 3 INV switch. Plus, you have inverted outputs for edges 1 and 3. According to ST-Modular, the slopes can be very short and snappy but also longer with up to 10 seconds. Slopes is also a very versatile module and brings a lot of organic movement into every modular system.