PATCH #3: "Sync Simple"

Earlier this year, Doepfer announced its new Basic System 3 (BS3), the latest in its line of complete, pre-configured Eurorack systems aimed at beginners, experts, explorers and purists alike.

To accompany the system, Doepfer — in collaboration with Stromkult — has designed a comprehensive Patchbook with fourteen different patch ideas for the BS3. Every patch comes with custom-made patch diagrams and a step-by-step-patching manual, making it easy for anyone to recreate and play with these patches.

While the patches were specifically designed for the BS3 and its configuration, most of the patches revolve around basic "building block" modules such as VCOs, VCFs, VCAs, mixers, envelope and LFOs and thus should be able to be recreated on a variety of systems — above all, we hope these patches may inspire you!

You can download the full PDF of the patchbook with all of the patches here (link goes to Google Drive).

Every individual patch is divided into an introductory overview of the patch, a section for the audio path, a section for the control voltage path and a final "play the patch" section with ideas on how the patch could be further tweaked and iterated upon.

PATCH OVERVIEW

This is a simple oscillator sync patch. A “sync sound” refers to the act of patching an output from an oscillator into the synchronization (sync) input of a second oscillator, which can create a large amount of interesting (often metallic sounding) overtones.

(the diagram for this patch includes both the audio and control voltage path)

AUDIO PATH

As sound sources, we use sine waves from both A-110-1 oscillators, which are summed via the A-138 mixer.

We send a saw wave from the first A-110-1 into the “sync” input of the second oscillator. This routing creates the oscillator sync the patch is named after. When the first oscillator ends a cycle, it resets the period of the second oscillator and forces it to have the same fundamental frequency. Note that in this configuration, the pitch relation of the second oscillator affects its timbre. The first oscillator in our patch is tuned to a C, the second to a G.

The signal from the A-138 mixer is routed to the A-108 VCF. The filter’s “24db LP” output is fed to the A-131 VCA before being distributed to our headphones or speakers.

CONTROL VOLTAGE PATH

Both of our envelope generators, the A-140-1 and the A-140-2, are triggered by gate from the keyboard/sequencer. The A-140-1 controls the gain of the A-131 through its “CV1” input. The second envelope from the A-140-2 goes to the “CV3” input of the A-108 to modulate its filter cutoff frequency.

The first ADSR from the A-140-2 is routed through the A-138j Janus Mixer. One of its output is fed to the “CV2” input of the A-108, creating another filter envelope. The other output called „Si Out B.“ goes to the “CV2” input of the second A-110-1, creating a pitch envelope. Note that since the oscillators are synced, this will create a change in timbre rather than pitch.

PLAY THE PATCH

Experimenting with the tuning of the oscillators yields significant changes in sound.

The envelope from the A-140-2, when routed through the A-138j, can be inverted using the “Inv” switch, altering the direction of envelope modulation (moving downward instead of upward).

Increasing the cutoff frequency on the A-108 accentuates the upper harmonics generated by the synced VCO.