🎹 ISLA v3.0.0 — ALIVE + LIVE

Let the Music Flow.

ISLA is ALIVE. And now, ISLA can listen LIVE.

Version 3.0.0 marks a major milestone in ISLA's evolution from an experimental musical signal-processing engine into an interactive audio application.

With ALIVE, listeners can open local recordings and explore ISLA's musical transformations. With LIVE, macOS users can process system audio continuously—including music playing through a browser—and listen through connected speakers or headphones.

At the heart of ISLA remains one question:

What if musical transitions could be softened, connected, and transformed through mathematics while preserving the character of the original performance?

This release brings that exploration closer to everyday listening.

✨ What's New in v3.0.0

🎧 ALIVE — Interactive Audio Playback

ISLA now offers an interactive terminal experience for exploring local music recordings.

Load mono or stereo WAV recordings.
Prepare and switch between Velvet, Legato, and Melt.
Compare transformations against the original audio using Bypass.
Play, pause, resume, stop, and replay recordings.
Inspect playback status and processing progress.
Perform file preparation separately from the audio playback callback.

ALIVE builds on ISLA's existing phase-aware DSP research and offline-processing foundation.

🌊 LIVE — Real-Time System Audio Exploration

For the first time, ISLA supports continuous processing of macOS system audio through a dedicated LIVE monitoring engine.

Using BlackHole 2ch as a virtual audio input, listeners can route supported system audio through ISLA and hear the result on their physical speakers or headphones.

LIVE introduces:

Continuous audio capture and processing.
Stereo support at 44.1 and 48 kHz.
Stateful frequency-domain harmonic processing.
Weighted overlap-add reconstruction across successive audio blocks.
Smooth switching between musical profiles.
Time-aligned Bypass comparison.
Device-routing checks and safeguards against unsupported output configurations.
Monitoring status, signal diagnostics, and explicit stream cleanup.

LIVE remains experimental and is not presented as a professional, hard-real-time audio solution.

🎛️ Three Musical Profiles

Velvet — Gentle harmonic softness

Explores a softer, less sharp harmonic texture.

Legato — Musical continuity

Explores a more connected musical impression.

Melt — Flowing harmonic transformation

Applies a more pronounced harmonic-smoothing effect.

Bypass — Hear the original

Returns to the original captured signal with the same LIVE processing delay, allowing comparisons without changing playback routes.

The current LIVE profiles use related spectral-processing mathematics at different strengths. Their musical descriptions express creative intentions rather than guaranteed perceptual effects.

🖥️ Guided Audio Setup

ISLA introduces an interactive device-selection workflow intended to make LIVE easier to configure.

After launching ISLA, enter:

setup audio

The guided setup helps select the required BlackHole capture device and an eligible physical stereo output.

Existing manual commands remain available for experienced users.

ISLA does not automatically change macOS system-audio routing or start monitoring during guided setup.

🧠 Engineering Foundations

Version 3.0.0 extends ISLA's deterministic DSP foundation with a practical playback and monitoring architecture.

Major engineering capabilities include:

Stateful, continuous harmonic processing.
2048-sample analysis windows with 512-sample processing hops.
Preserved analysis and reconstruction state between blocks.
Separated audio callbacks and DSP worker processing.
Bounded buffering and explicit failure handling.
Regression tests for signal continuity, playback behavior, device management, and DSP invariants.
Continued support for legacy Python interfaces and existing offline-processing functionality.

ISLA's ALIVE and LIVE engines intentionally use different processing pathways. Their outputs are not guaranteed to be identical.

🧪 Testing and Validation

ISLA v3.0.0 builds on automated tests and native macOS acceptance work.

Recorded development validation includes:

Python regression testing and cross-platform CI.
Actual macOS audio capture through BlackHole 2ch.
Playback through physical audio outputs.
Mode switching during continuous playback.
Numerical waveform and continuity verification.
Native testing at 44.1 and 48 kHz.
Device-routing validation and audio-stream cleanup.

Owner listening confirmed that all three LIVE modes produced subtle differences, with Melt preferred during the documented listening session.

These results support the functionality of the experimental system, but do not constitute comprehensive musical-quality or hardware-compatibility acceptance.

Additional stress, long-session, physical-disconnection, and broader device testing remain necessary.

🚀 Getting Started

ISLA is open-source and available on GitHub:

https://github.com/dfeen87/ISLA

For the macOS terminal experience, install the Python playback dependencies and launch:

python -m pip install -e '.[playback]'
python -m isla

For LIVE audio, install BlackHole 2ch separately and follow the repository's macOS routing instructions.

The local-file ALIVE experience does not require BlackHole.

Python 3.10 or newer is required.

Please review the README's setup, audio-routing, safety and recovery instructions before using LIVE.

⚠️ Current Limitations

ISLA is an experimental audio research project.

LIVE currently targets macOS 13+ with BlackHole 2ch and a separate physical stereo output.
The Python-based LIVE system is not guaranteed to meet hard-real-time audio requirements.
Monitoring introduces latency and may affect video synchronization.
Processing is not automatically loudness-normalized.
Wider device and operating-system compatibility remains unverified.
The JUCE VST/AU plugin pathway remains experimental and is not certified for professional real-time operation.
A documented legacy nonzero-strength chunk-streaming limitation remains under investigation.

ISLA should not be considered a finished commercial audio processor.

🔬 What's Next?

Future research will investigate whether Velvet, Legato, and Melt can develop more independent musical characteristics through carefully validated DSP improvements.

Additional priorities include:

Mathematical robustness and numerical precision.
Reproducible musical listening comparisons.
Greater perceptual differentiation between processing modes.
Long-duration LIVE stability.
Audio-performance optimization.
Broader native macOS acceptance.
Future graphical interfaces and other listening experiences.

Experimental changes will be evaluated independently before inclusion in a release.

❤️ A Special Dedication

ISLA is dedicated to Isla, the creator's niece.

Her name represents the inspiration behind a project that brings together musical expression, mathematical curiosity, and thoughtful engineering.

What began as an exploration of phase-aligned note smoothing has grown into a working experimental audio system.

ISLA continues to evolve through human creativity, open-source collaboration, and AI-assisted engineering.

Special recognition goes to the foundational contributions of Microsoft Copilot and Google Jules, as well as OpenAI's ChatGPT and Codex in advancing ISLA's interactive ALIVE and LIVE experiences.

And to everyone who listens, experiments, tests, and contributes:

Thank you for helping the music flow.