Non-Visual Beats: Redesigning the Groove Pizza
William Payne, Alex Xu, Amy Hurst, S. Alex Ruthmann · 2019 · Proceedings of the 21st International ACM SIGACCESS Conference on Computers and Accessibility (ASSETS 2019) · doi:10.1145/3308561.3354590
Summary
This demonstration paper describes the accessible redesign of the Groove Pizza, a popular free web-based drum step-sequencer developed by NYU’s Music Experience Design Lab (MusEDLab) that reaches thousands of users per month. The original Groove Pizza uses a circular visual interface where users click nodes on concentric rings to create rhythm patterns — each ring represents a different drum sound and each node represents a beat position. However, the original was built entirely with SVG images, "invisible" UI layers, and custom animations, making it completely incomprehensible to screen readers. Two of the paper’s authors are Groove Pizza developers who recognised these barriers. The redesign, built with Tone.js, p5.js, and p5.speech JavaScript libraries, addresses two core challenges: creating keyboard input that maps meaningfully to the musical instrument’s affordances, and providing screen reader output that conveys interaction feedback without interfering with the music-making experience. The redesigned interface presents sixteen nodes per loop (called "slices") across three concentric circles (instrument layers), with full keyboard navigation replacing the mouse-only original.
Key findings
The redesign implements two custom keyboard mappings for rhythm sequencing. In the first mapping, the top row of letter keys (Q-P) toggles odd-numbered beat nodes while the second row (A-L) toggles even-numbered nodes. This design leverages a fundamental feature of Western music: even-numbered beats sound "off of" the pulse, so standard rhythms can be created safely with the top row while more syncopated patterns involve the second row. A second mapping reduces the number of keys needed by grouping four consecutive nodes per top-row key with the second row selecting within the group. For audio output, the paper identifies a key tension: music output and text-to-speech compete as audio streams, making it difficult for users to understand both simultaneously, while non-music sounds during performance are distracting and hinder creativity. To address this, the redesign implements three audio modes: "Practice Mode" (music quieter, text-to-speech amplified), "Sonification Mode" (most text-to-speech replaced by synthesized tones where pitch encodes position and timbre indicates present/absent), and "Performance Mode" (all non-music audio disabled, full music volume). This mirrors the distinction between exploratory and performative modes found in professional music tools like Max MSP.
Relevance
This paper highlights a significant gap in creative technology accessibility: while affordable music software has democratized music composition for sighted users, blind and visually impaired musicians face substantial barriers. Digital audio workstations like Ableton Live and GarageBand use visual grid interfaces with hundreds of on-screen controls that are inaccessible to screen readers. The piano roll — the standard interface for MIDI editing — relies entirely on drag-and-drop visual interaction. Third-party accessibility patches exist (such as Dancing Dots, which has added JAWS support for nearly thirty years) but cost extra and can break with software updates. The Groove Pizza redesign demonstrates that accessible music creation tools can follow universal design principles rather than requiring separate assistive add-ons. The keyboard mapping approach — designing key layouts that mirror the musical structure rather than simply providing generic grid navigation — is an important design insight for any accessible music tool. As a demonstration paper, this is preliminary work: the redesign has received informal feedback from two blind musicians and one blind non-musician but has not undergone formal user testing with visually impaired participants.
Tags: music accessibility · blind · visual impairment · screen readers · sonification · keyboard accessibility · music creation · web accessibility · universal design