DAISY DUB -T HE P LAYABLE DELAY Rasmus KJÆRBO 1 1 Sound & Music Computing, Aalborg University, DK 2 Rumkraft Aps, Copenhagen, Denmark ABSTRACT The surge of advanced microcontrollers allowing for real- time processing of audio has taken the DIY world of instru- ment and effect builders by storm. This project utilises the Daisy Seed barebone platform from Electrosmith to imple- ment a high definition playable musical delay for dub mix- ing and live performance. An important aspect of the plat- form is the capability to execute C++ code with extremely low latency at 24-bit 96kHz audio quality, comparable to state of the art delays like the contemporary and widely used El Capistan by Strymon Engineering. A second as- pect of the project seeks to replicate the specific character and playability of vintage delay Roland SDE-2500 - one of dub pioneer King Tubby’s favourites. Finally, the project explores rapid prototyping of real-time audio effects and sound generation with Max and Gen by Cycling74 and the translation to executable and embeddable Daisy Seed code with the Max object, Oopsy by Electrosmith. Evaluation, design, and implementation was conducted alongside a se- ries of qualitative interviews with avid music producers, sound engineers and live performers with expertise in de- lays, sound design, and dub mixing. 1. INTRODUCTION Music producers, sound designers, audio effect developers, DSP programmers, musicians, sound-, mixing- and mas- tering engineers, and live performers all utilize delay lines. Whether for inspiring and driving polyrhythms generated by the interplay of freely timed or synced repetitions of au- dio or for swelling sound effects during a live performance, working with analog or digital audio will most surely take your journey past a plethora of delay lines. Many versions of the delay effect exist, each with its own unique take on controlling and bending time. In this project, I construct the Daisy Dub Delay (see fig. 1) a digitally controlled, high definition delay with design and sound characteristics of the dub era in the 60s and 70s Jamaica and United Kingdom. In said era, dub produc- ers and sound engineers usually worked as electrical engi- neers, constructing their own unique sound effects in order to stand out and champion the record and sound system scene [1]. The delays from the 60s and 70s where pre- dominantly analog, rack mounted and had few knobs and Copyright: © 2021 the Authors. This is an open-access article distributed un- der the terms of the Creative Commons Attribution 4.0 International License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Figure 1. Daisy Dub Delay - https://youtu.be/ fcGmwTvWMJk buttons along with simple LCD displays. Advanced de- lays of that time offered layers of menu diving - great for sound design, but hard for live manipulation of parameters. Lastly, you still needed to patch delays in series to other ef- fects to achieve the out-of-this-World soundscapes, as dub music often explores. The design goal of this project is to offer simplified access to direct controls of the delay line, with a limited but ex- pressive amount of extra sound design options accessed via a display and a rotary push encoder. Concealing the ma- jority of parameters in a simple and accessible menu sys- tem maximizes playability without compromising sound design possibilities. 1.1 State of the art 1.1.1 El Capistan by Strymon Engineering - released 2010 El Capistan is a 24-bit 96kHz delay with various types of modulation, input stage filter, filter in feedback path, and an algorithmic spring reverb. A go-to delay for musicians and dub mixers alike. The form factor is great, but in- teraction with the unit is limited to only five knobs, two three-way switches, and two stomp buttons (bypass and tap tempo) (see fig. 2). One particular thing about El Capistan is the MODE A:B:C switch, which - depending on your TAPE HEAD selection - will vary your delay speed in ei- ther an single octave up/down or changing delay time from your selection to a dotted version. Noteworthy attributes of Strymon’s El Capistan: Playable