scaled the coefficients
        // by coefScaleFactor, the output is reduced by the same factor, so
        // adjust the gain to scale the output of iir2 back up.
        gain.gain.value = coefScaleFactor;
        gain.connect(merger, 0, 1);

        merger.connect(context.destination);

        source.start();

        // Rock and roll!

        context.startRendering()
            .then(function(result) {
              // Find the max amplitude of the result, which should be near
              // zero.
 