On GotSound.org we are using wavesurfer.js to play sounds in a browser.
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MediaElement fallback to support old browsers like Internet Explorer not always works.
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this series is done through layering and processing many samples of drum sounds i synthesised using various plugins namely xoxo's vst's and zynaddsubfx mixed with some old hardware samples i made a long time ago. there are 4 packs of the same series : PERC SNARE KICK and HATS all using the same process.