Tag: vactrol

Cereal Instruments ‘thump’ – DIY Build

Cereal Instruments 'thump' - DIY Build

Cereal Instruments - THUMP - Completed Front

Cereal Instruments ‘thump’ allows you to send two signals through a gritty vactrol amp with low pass gate modes & plenty of gain/distortion. Sounds cool huh? We thought so too and thought it only made sense that the ‘thump’ was our next build. One thing to note is that the ‘thump’ is unlike its brethren kin with regard to power. It is Cereal Instruments first active module, meaning it requires power to operate unlike the ‘mesh’ or ‘swerve’.

The ‘thump’s aesthetics are a matte black panel with orange knobs and white silkscreen give the modules their own unique look. The PCBs that Cereal Instruments uses are excellent quality. They soak up solder like a sponge grabs water. This makes for a stress free build. Speaking of the build, the ‘thump’ would be recommended for intermediate builders and above.

Novice builders could struggle with some of the tight spaces, double PCB layout and the giant pot/switch that needs to be wired in a specific manner in order to get the correct switching.

Let the soldering begin…

Since there are 2 PCBs, start with the logic board first. This is the one that doesn’t have the jack/pot mounting spaces (that is the control board). Resistors, diodes and caps were first up (one cap will be placed on the control board). We used top down soldering instead of bottom soldering due to the ease of access. After these were tacked down, the IC sockets were next. 

Dab one pad with solder and then line up the IC socket with the holes. Heat up the solder and lightly push the IC socket into the melted solder. This will hold everything in place when you turn the control board over and complete the IC socket soldering.  

The main power header is next followed by the standoffs and the electrolytic cap. This capacitor is soldered on the backside of the logic board.  Lastly, attach a wire from the top CV jack pad to the outer CB pot pad as shown in the photo below.

Detailed - Install Wire
fin Divider

Fonitronik Ps3100 Triple Vactrol Resonator – Time Lapse Build

Fonitronik Ps3100 Triple Vactrol Resonator - Time Lapse Build

In our latest build we take on the Fonitronik Ps3100 Triple Vactrol Resonator – A clone of the lovely triple resonator from the rare 1977 Korg Ps3100 polyphonic modular.

What we have here is basically a module combining three bandpass filters (vactrol based filter core from the PS3100) with a simple resettable LFO and some clever CV and signal routing.  The LFO is normalized to the common CV input, which is normalized to the 3 single CV inputs. the 3rd CV channel can be inverted.

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Nonlinear Circuits Vactrol PiLL Eurorack DIY

Time Lapse Build: Nonlinear Circuits Vactrol PiLL (NLC Vac PLL)

Violent Behavior PCB

In this build, we take on the Nonlinear Circuits (NLC) Vactrol PiLL module. While the build itself wasn’t a difficult one, it did take some patience when it came to soldering the LED after mounting the panel. With most of the components already mounted, we recommend you use a very fine time on your soldering iron to be able to get to the LED solder points.

Also, make sure you don’t have a lot of coffee or caffeine in your system when it comes to building this module… save that for when you are done!