Web Audio Tech
I have spent my day diving into Service Workers and Push Notifications since I wanted my webapp STQ (a German Star Trek trivia quiz app) to send out push messages to users. This has probably been the most wanted feature ever since.
Addy Osmani’s guide on PWAs and this codelab by Sam Dutton on implementing push notifications are a great start. But since the technology is still cutting edge, there were a two gotchas along my way, which I want to share.
If you are anything like me, you are curious about the current state and the future of Web Audio. So I asked one of the Web Audio API spec editors, Mozilla’s Paul Adenot, if I could shoot some questions. He said sure, and was so kind to take some time and answer them elaborately. Here are his answers, stuffed with lots of useful information.
Did you come across digital clipping in web audio apps? I certainly did several times (mostly in my own apps though). This undesired effect occurs when you play several sound sources at the same time, which results in a signal that is louder than the maximum of 0 dBFS. Since a digital system is unable to reproduce higher amplitudes, you will hear nasty distortion and get an unworthy waveform looking like this:
I just wanted to mention that I did this thing called Beatsketch last year. It lets you make music on the web without having to know much about making music.
BeatSketch from Sebastian Zimmer is a collaborative music production tool that Sebastian developed for his Master’s degree in Computer Science. A song consists of multiple tracks, and each track is backed by a grid-based sequencer. Any changes you make are synchronised between connected collaborators immediately. It also supports mixing the final song down to a WAV file for downloading. An impressive set of features and a very useful exploration of possible methods of implementing collaborative working.
Chris Lowis on Web Audio Weekly #43
Has anybody created an emoji keyboard that’s actually a piano keyboard for writing musical notation? Wanted a quick way to tweet a melody.
— AudioGrains (@AudioGrainsBlog) 5. Januar 2016
Inspired by @AudioGrains tweet, I made this little Emoji Piano.
Emoji Piano lets you create simple melodies and encodes them with Unicode emojis which you can share and tweet.
THREE.js developer Mr.doob has posted an important comment on this.
WebVR matters. And the great WebVR Boilerplate by Boris Smus allows to get started with it immediately.
Playing around with it, I got the idea to use the Web Audio API to spatialize the sound of an object within the matrix, so that a person wearing a headphone could not only see, but also hear where an object is located.
Since the Web Audio API is great, you can do that with ease.
Currently, I’m doing some XML manipulation and transformation in the web browser. I have encountered some obstacles, tips and thoughts that I want to share with you.