NexusUI is not a ‘canned solution’, but is a set of components that can be used to build custom interfaces.
The BBC has published some online demonstrations that recreate the sounds of the BBC Radiophonic Workshop using the Web Audio API:
Explore the BBC sound of the 1960s with our 4 demos of Radiophonic equipment, built with the new Web Audio API standard. Each demo comes with commented code, so you can learn how to build your own audio applications.
The demos include simulations of the Workshop’s gunfire effects, the ‘Wobbulator’, tape loops & a ring modulator.
Alex Gibson’s WAVE-PD1, aka WavePad, is a basic synth toy that sounds a bit like a theremin, built with HTML 5 audio.
WavePad has a simple touchpad UI and generates sound based on the waveform and filter settings that you can select. It can also be affected using delay and feedback settings.
While it’s unsophisticated as a synth, it’s built with HTML and delivered via the Web, so it should theoretically be cross-platform. At this time, only about 25% of the smartphones in use support HTML5 audio.
Browser-based virtual studio Soundation Studio has added support for external MIDI recording.
Now you can connect an external keyboard to one of the virtual instruments in Soundation and record directly to the “cloud”. Soundation Studio comes with 4 different synthesizers, a drum machine and a sample player. You can also use the virtual keyboard in Soundation to record a part.