Web synth is a browser-based [daw] and audio synthesis platform.
Try it now at https://synth.ameo.dev/
It's 100% free and open source. It's built on the WebAudio API and makes heavy use of modern web features like WebAssembly, AudioWorkletProcessor
and SharedArrayBuffer
for things like implementing custom digital signal processing code and generating realtime visualizations.
It shares similarities with other tools like Bitwig Grid and audio programming environments like Pure Data, but it also has most of the features you'd expect from a traditional DAW like a [midi-editor], [sample-library], [signal-analyzer], and several built in synths and effects.
You can also check out a standalone demo of web synth's [fm-synth] module here: https://synth.ameo.dev/fm.html
Or, watch the (out-of-date) demo video to get a feel for what the full app can do: