That 'ring' you hear when tapping is a sign of low damping: the wood doesn't dissipate energy as fast, so it rings longer. IRW does tend to have higher damping (a shorter 'ring') than BRW or Blackwood, but, like all woods, it tends to vary a lot in that regard. I've never seen a piece of IRW with damping as low as the best BRW, but a good piece of Indian can be close to an 'average' piece of Brazilian. A poor piece of IRW will have twice as much damping as a good one. Some of the 'stump' BRW is almost the same.
I've found when tapping wood that I get fooled sometimes. Based on taps, for example, I thought that Persimmon had fairly low damping, but found on making an actual measurment that it was more like maple than a rosewood. I think, in that case, it was just so massive that I had to really hit it hard to get it moving, and so it took a while to run down. You'll see the opposite in some ways with balsa and other low density woods: they aren't very good as 'flywheels', and lose energy fast moving air. I always thought balsa had high damping when I was tapping thin sheets, but when I got a piece that was 2" square and measured it, it was right in there with spruce in that respect.
If you really want to hear 'cardboard', try Mesquite burl. The piece I've got is somewhat inferior to Masonite as a tone wood, with very low stiffness and high damping. It looks interesting, though, and smells nice...
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