'Pan Flute' - How to make this movie-inspired, all-analog Synth Patch in Eurorack Modular

video upload by AJH Synth Official

"This was loosely inspired by the 'pan flute' sound from the film 'Aguirre: Wrath of God', and uses a single VCO, white noise, and envelope-controlled filtering to simulate the pipe and breath elements that form the sound. Fixed Filter Bank sculpts the noise, removing low frequencies and pushing selected highs, before being mixed into the Sonic XV's bandpass filter along with the square wave from the VCO. Importantly, the FFB's wet/dry mix is also controlled by an envelope here, a rare feature on a filter bank. Pulse width modulation from red noise ads a subtle distortion to the oscillator, and the VCA in the Dual LFO is used to ad optional pitch vibrato and VCF frequency modulation.
Patch sheet PDF: https://kvisit.com/8AE/_v8G

Aside from the flute scene (see link in video), the movie soundtrack was mostly the brilliant work of Popul Vuh, and makes the official album release worth listening to regardless of the movie, with memorable use of Mellotron. However, the Werner Herzog movie itself is equally brilliant and memorable, a captivating, immersive experience to watch, made on an unimaginably small budget, yet a direct influence on Coppola's 'Apocalypse Now' a few years later.

The AJH SYNTH Eurorack range consists of high-end modules, all hand-made in the UK, most of which are based on classic, vintage designs, authentically recreating the circuitry of much sought-after analogue instruments and technologies of the past, whilst greatly expanding them, and bringing them to modern Eurorack levels of convenience, limitless flexibility, and reliability.

Check out the AJH Synth playlists for module 'User Guides', and 'Patch of The Week' videos, which will be either performances or 'how to' guides, detailing functions/methods, and a range of sounds, some familiar, some less so, containing a patch sheet at the end to show you how to construct it for yourself.

Video by @DreamsOfWires

PATCH NOTES:
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Green dots show approximate pot and switch positions. Pots and switches that do not have green dots are not used in this patch, and should be left at their zero or off positions. Multiple cables may branch to different destinations, this is where some form of multiple should be used.
This patch needs a lot of fine-tuning, so precise pot positions cannot possibly be illustrated, but this should serve as a starting point, from where further experimentation should be applied. The video tries to explain what is happening with the core modules, which should make it easier to understand what needs fine-tuning.
KEYBOARD: Here the controller's MOD output is used to send Aftertouch, but alternatively Velocity, or direct control from the MOD wheel/strip could be sent to the Dual LFO's CV input instead, depending on your controller and personal preference. DUAL LFO: Output goes directly to EXP-CV of the VCO, and IN 1 of the CV MIX.
CV MIX: This module is used here to combine the CV from the LFO and Contour Generator 1, then to fine-tune it, before sending to Sonic XV and Fixed Filter Bank.
FIXED FILTER BANK 914: The IN 2 pot needs to be at zero - this sets the Dry level to zero if nothing is connected to the IN 2 socket, so that when the envelope changes the Wet/Dry level it is in fact affecting the output level of the module, as only a varying portion of the Wet signal is then sent to the Muting Mixer.
Modules used from top-left to bottom-right: Glide + Noise, Vintage Transistor Core VCO, Sonic XV, Contour Generators, Discrete Cascaded VCA, Dual LFO + VCA, CV Mix, Muting Mixer, Fixed Filter Bank 914."