Patch of The Week: 'Filter Drums' Part 1 - Analogue Cowbell w/ Fixed Filter Bank 914 (& VCF Clave)

video upload by AJH Synth Official

"This week's patch is the first of a short series showing ways to use filters for vintage rhythm/drum machine percussion style sounds, beginning with an analogue cowbell-type sound using the Fixed Filter Bank 914.

00:00 Patch of The Week: 'Filter Drums'
02:07 Patch Sheet

Some filters can be used to create tones without any input sound, simply by pushing them into self-oscillation (raising resonance beyond it's threshold point), but the Fixed Filter Bank is not a regular filter/VCF, so it works a little differently. Rather than controlling the overall frequency of the filter, each of it's bandpass filters has a preset frequency, for which you control the level. On the AJH Synth module they are deliberately tuned to one of two pitches when pushed into feedback, which makes it more musically useful. Here, I mix in some white noise to add texture to the feedback frequencies.

For comparison, I also included the Ladder Filter here to demonstate how a typical VCF (which can self-oscillate) can be controlled by a sequencer, with the steps controlling the pitches it produces. The point is that either module has it's advantages when used to synthesize particular sounds. In this video the ladder filter is producing simple tuned claves."

Patch of The Week: No-Input Filter Drums Part 2 - Using VCF Self-Oscillation to create Percussion

video upload by AJH Synth Official

"This week's patch shows some ideas for using self-oscillating analogue filters to produce vintage drum machine inspired sounds, the basis of which can be used to emulate such sounds as the clave, bongo, cowbell, and kick/bass drum of early rhythm boxes. I used the sounds of the Roland CR-78, TR-77 and Acetone FR-2L as inspiration here, but in a later Patch of The Week video I'll be recreating some sounds of 70's machines more directly, using VCOs and noise sources. In the meantime, the methods contained here might be of interest to those wanting to make some simple percussive accompaniment with a limited number of modules. At the end of the video I'll show some vintage-inspired patterns using the modular as a 4 voice drum machine, without needing to use samples or a sampler. Patch notes and link to downloadable patch sheet below.

Index:
00:00 Intro
00:25 VCF Clave
01:12 Fixed Filter Bank Bongo/Cowbell
02:27 Gemini 2412 Bongo
03:20 VCF Kick/Bass Drum"