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BufferSourceNode to AudioParam Connection

From: Nick Thompson <ncthom91@gmail.com>
Date: Mon, 5 Nov 2012 20:40:47 -0500
Message-ID: <CAOXEKCMRuvcY5_gEjJ4s84Mhtrzvw1DyOz75sspMSkaHHmsbBg@mail.gmail.com>
To: public-audio@w3.org
Hey all,

I'm currently experimenting with sidechain implementations, and I've
noticed a discrepancy in the way AudioNode's connect to AudioParams.

If you route an Oscillator into an audioparam, the output of the Oscillator
does not reach AudioContext.destination unless you specifically connect it
thereto. Example: http://jsfiddle.net/Ddz3y/1/ In this example, the output
of one oscillator simply modulates the gain on the output of another
oscillator, as you would expect.

However, if you route a BufferSourceNode into an AudioParam, the output of
the BufferSourceNode still reaches AudioContext.destination even if you
don't specifically make that connection. Example:
http://jsfiddle.net/VdLf6/Here, you'll notice the same setup as in the
previous example, and you'll
notice that the output of the OscillatorNode is clearly audible when the
buffer sample's kick drum is played, but at the same time, the buffer
itself is fully audible even though I did not specify a connection to
AudioContext.destination (unless you're counting the connection from
bufferNode -> gain.gain, gain -> context.destination).

I'm not sure what to make of the discrepancy here. A bug in the
implementation? Or perhaps that's the expected behavior? If that's the
case, I feel the documentation should be updated to reflect that, as it was
pretty unexpected. Or maybe I'm just approaching/using this feature
incorrectly? If that's so, please correct me!

Thanks
-Nick
Received on Tuesday, 6 November 2012 01:41:15 UTC

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