Well that is just simply disturbing. Really.
Walnut? Not nearly dense enough. Maple, possibly. But certainly not walnut. Besides, both walnut and cherry for that matter will add their unique colorations to the sound.
And I do hope that we migrate this discussion back to the aeron chair.....a much less disturbing picture. Though I do usually sit in a copy of the less expensive herman miller chair mentioned earlier - the Ergon3 not as comfortable as the Stressless Recliner that I would like to afford, but a pretty good desk chair, especially for the price.