Greetings to everyone. For the 432 Hz and 528 Hz communities; for the theorists Robert Grant, Shannon de Bie, Robert Comber, Bo Constantinsen and Ananda Bosman; and to the families and legacies of those who are no longer with us: Maria Renold and Zhu Zaiyu. It is a great honor to help the world see and hear, side by side, the results of your work.
From the beginning, I was moved by a question: are there correct frequencies for musical notes? In groups, so that the instruments can play together, it is necessary to tune them to the same frequency. Historically, this reference was chosen as a practical rounding, within a comfortable range for the human voice and ear. Today, however, I believe that we already have the technology and information necessary to improve this tuning, aligning the musical notes more precisely with mathematics, geometry and cosmology.
Over time, notable names have focused on these ideas to create musical scales. And some of the most important theorists to address 432 Hz and 528 Hz are listed below.
Robert Grant, bestselling author in mathematics and geometry, and one of today’s most prominent advocates of 432 Hz, with the 24-note PTT system that includes both 432 Hz and 528 Hz.
Maria Renold, musicologist who worked closely with Rudolf Steiner and developed two tuning systems inspired by his ideas, now among the most widely used in the 432 Hz community.
Shannon DeBie, exploring exact numerical relationships to create mathematically stable musical intervals.
Robert Comber, with 72 notes per octave, offering higher microtonal resolution for astrological and harmonic correspondence analysis.
Bo Constantinsen, with the sequence of “the sacred numbers,” considered highly significant in mathematics, geometry and cosmology, and associated with therapeutic and spiritual properties.
Ananda Bosman, with one of the simplest and most versatile adaptations, promoting the use of 432 Hz while preserving Equal Temperament.
Shu Zaiyu, the creator of Equal Temperament, presented here in 440 Hz to support tuning comparisons.
Toni Mazzotti, with two original systems: the Torus Triplets, based on the 18 triplet number combinations emerging from the three toroidal orbit positions, popularized in recent decades as healing frequencies; and the Spiral Tuning 144-EDS (coming soon).
Learn more about the 432 528 Tunings Theorists here.
🎹 432 528 Tunings app
432 528 Tunings is a free online educational application that tunes instruments, converts audio and compares the main alternative musical tunings.
→ What the 432 528 Tunings app does
- Compares soundly and visually the main tunings in 432 Hz, 528 Hz and 440 Hz
- Plays notes through MIDI, computer keyboard, and mouse cursor
- Operates online through browsers, on any system or device
- Converts audio between 432 Hz and 440 Hz with full quality
- Tunes software and hardware instruments via MIDI ports
- Show detailed descriptions of each tuning and its theorist
The application is already available at: https://tonimazzotti.com/432-528-tunings/
Click on the 432 528 Tunings logo to access the start guide.
12 Tunings, 8 Theorists
Shortcuts
Tools
Waveforms
Viewers
Converter
In and Out
💡 Future Plugin Architecture
With the 432 528 Tunings application, it is already possible to tune instruments, convert audio, and control external software and hardware. The next step is to bring this system directly into professional music production environments.
The goal is to develop two dedicated plugins for digital audio workstations (DAWs), such as Ableton Live, Logic Pro, Cubase… A Master plugin will act as the central tuning controller of the project, while a Follower plugin will apply and distribute the tuning across instruments and channels in real time.
Both plugins are planned to support Windows, macOS, and tablets, with current compatibility for MPE and a future-ready architecture for MIDI 2. However, this stage requires extensive development, cross-platform testing, system integration, and platform certification (including Apple authorization).
This Plugin Ecosystem will allow full real-time tuning control across entire DAW projects, something that is currently not available in standard workflows.
→ What the Master plugin will do
- Centralize tuning control within the DAW
- Apply alternative tuning systems such as 432 Hz and 528 Hz
- Control external hardware and software via MIDI
- Support automation across the entire project
→ What the Follower plugin will do
- Follow the Master instance or operate independently
- Apply tuning per channel or instrument
- Use Pitch Bend, MPE, and future MIDI 2 protocols
- Support independent automation and fine control
🔍 The Problem in Music Production
Although the tunings of 432 Hz and 528 Hz are widely debated and increasingly adopted, their practical and precise use in music production remains complex and fragmented. Tuning through MIDI Polyphonic Expression (MPE) offers greater compatibility, but lower tuning accuracy, acting mainly as a transition solution between MIDI 1 and MIDI 2.
MIDI 2 was officially released in 2020, but its total adoption depends on software updates and new hardware, a process that will occur gradually in the coming years. Consequently, there is a clear disconnection between the available musical tuning knowledge and the accessible and reliable music production tools.
💛 Partnership
This project is currently in development and requires funding to move forward. If you are interested in supporting this work or collaborating, please get in touch.
🔓 Custom License
This software is made publicly accessible for educational purposes.
You are allowed to:
- Use the application
- Study and analyze its behavior
- Reference its concepts with proper attribution
You are NOT allowed to:
- Copy or replicate the system in whole or in part
- Use the software or its logic in commercial products
- Modify and redistribute the system
- Create derivative software or systems based on this application
For commercial use, partnerships, or licensing inquiries, contact me:
Custom License: tonimazzotti.com/license
Terms of Use: tonimazzotti.com/terms
Privacy Policy: tonimazzotti.com/privacy
All rights reserved.