Apps by Jeff Holtzkener
Concentric Rhythm app icon

Music

Concentric Rhythm

Jeff Holtzkener

$3.99 4.65 · 1 storefront · 43 ratings In-app purchases unconfirmed
Open on Apple

About this app

Concentric Rhythm is an interactive tool for generating, developing, and exploring musical patterns. It uses geometric transformations and many other simple processes to create, develop, and evolve music. The looping musical timeline is visualized as a circle, which allows you to treat musical patterns as concentric shapes. This makes performing geometric transformations such as rotations, reflections and folding very natural and intuitive. It also provides tools for melodic lines such as random-walk generation and scale-based inversion and transposition. You can generate rhythmic lines using cross-rhythms or the Euclidean algorithm, and allows for great visualisations of complex polyrhythms. Concentric Rhythm now allows you to assign each pattern to a different MIDI channel and send your results to other MIDI compatible apps or devices. Concentric Rhythm was originally developed as a new way to improvise electronic music, but it is also a great tool experimenting with and developing musical material, or just for casually playing with music in a unique, hands-on, way. Many of the ideas here were inspired by the book ‘The Geometry of Musical Rhythm’ and this app is a powerful tool for anyone who is interested in exploring these ideas. But at the same time is easy enough to use that anyone (even with no musical or mathematical background) can make interesting musical patterns and think about the musical world a little differently. Note: There are known compatibility issues when used with AUM, especially on iOS 14

Latest release

What’s New

Version 3.0.4 Mar 4, 2021

- can auto-save last MIDI Send value - significant improvements for Audiobus and AUM hosting

Audience growth

Ratings growth

Steady
7-day gain +0
Ratings / day 0.0
30-day gain +0
US rating-count history
43 ratings
43 Aug 24, 2026 · 43 ratings Aug 24, 2026

Baseline captured. Growth appears after the crawler observes a changed rating count.

Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.

Price tracking

Price intelligence

1 captured event
Current $3.99
Historical low USD 3.99
Paid → free
Price history
Current $3.99
$3.99 $2.00 Free Aug 24, 2026 · $3.99 Aug 24, 2026

First snapshot captured. The trend line starts after the next crawler price observation.

  1. First observed Aug 24, 2026 · 1:57 AM $3.99

Screenshots

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