Instruō - ceithir overview

ceithir is now available to purchase direct from: https://www.instruomodular.com/shop • Quad stereo mixing VCA Morphable filter modes  • Stereo enhancement • Internal LFO modulation  • Optimised Oscillator mode  • Pingable resonance • Multiple limiter types The culmination of years of filter experimentation at Instruō, ceithir is a quad state-variable filter and resonator system that expands upon the sonic architecture first introduced in the I-ō47. Each of its four analogue filter cores can operate independently as a traditional state-variable filter, a resonant sine waveform oscillator, or a precision pitch-trackable resonator, offering low pass, band pass, high pass, notch, and morphable responses alongside extensive CV control. Integrated waveshaping and soft-limiting circuits allow ceithir to move effortlessly from subtle harmonic enhancement to aggressive resonant saturation, while dedicated strike inputs transform each filter into a playable percussive voice. Far beyond a conventional filter bank, ceithir is designed as an animated stereo sound environment. Advanced Morph and Width controls generate immersive spatial movement through phase manipulation by all-pass filtering, while four internally routed trianglewave LFOs create evolving modulation networks capable of continuously reshaping frequency, resonance, stereo enhancement, and timbre. With parameter linking, global frequency control, and integrated master stereo routing options, ceithir delivers the unmistakably musical character of Instruō filters on an entirely new scale. --- Hello! I'm very excited to formally announce the ceithir. This has been very much a passion project of mine that developed from a winter design project beginning ~christmas 2024. This module design idea paralleled a plan to document the design process to a greater detail than I have previously with Instruō modules. There is now a multi part series of behind-the-scenes videos I have produced detailing various stages of module design. I tried to focus each one to be relatively stand alone, highlighting particular stages of my design and troubleshooting/refinement processes.    • Instruō - ceithir   This video is a more typical module overview in my long form style (It's easier to make a long video than it is a short one!). ceithir is a BIG module! And is not necessarily the most practical addition to all systems... But if you like it's features and tone, a more practical option is the ceithir's older/smaller sibling: the I-ō47 (which is also featured in this video). I hope you enjoy this module, or it's design video series, or both! The fact that there is support and enthusiasm for this scale of ridiculous design project is something I cannot thank you all enough for. Please feel welcome to join us over on Discord and at various trade shows out there. Cheers! ~Jason 00:00:00 Instruōduction 00:02:50 single filter fōcus 00:04:17 INPUT 00:06:33 Q 00:09:06 INVERTING INPUT 00:10:59 MULTI-MODE OUTPUTS 00:13:08 CV INPUTS 00:16:57 MORPH 00:19:14 OUTPUT (LIMITER) 00:22:33 STEREO OUT 00:23:57 LFO 00:26:19 I-ō47 mini-video feature 00:29:52 ceithir global features 00:31:44 INPUT NORMALLING 00:32:56 MEGA STEREO 00:33:53 TRUE STEREO 00:34:46 GLOBAL 1V/OCT 00:36:54 TRUE STEREO SUMMING CONFIGURATION 00:38:53 ARM PHASERS 00:41:40 MASTER LIMITER 00:44:32 MODULATION BUS 00:45:46 MODULATION BUS - FM 00:48:52 MODULATION BUS - ANIMATE 00:53:26 Resonator Mode 00:56:46 RESONATING COMPLEX AUDIO 01:02:46 QUADRATURE SINE WAVES 01:06:09 STRIKE INPUT (KICKS) 01:18:24 Oscillator Mode 01:20:42 4-QUADRANT / RING MODULATION 01:21:37 AMPLITUDE STABILISATION 01:23:58 QUASSILLATOR (QUAD-OSCILLATOR) 01:26:29 Parameter Link 01:28:59 STEREO TWIN PEAK