Wood blocks underneath components?? snake oil?

Yes. Snake oil. Cheap snake oil (in this case, free), but snake oil nonetheless.

Personally, I put my components on the properly engineered feet they came with. Well, except for my satellite receiver. That, I must admit, I balance on top of my favorite house plant (only lightly watered), with a rubber band on the left rear corner, wrapped around a very special Brasilian rosewood #2 pencil. No varnish or paint on the pencil, naturally, but rather lightly oiled and hand-rubbed for the best resonance control. The olfactory presentation of the receiver is much improved when following this procedure.

Okay, all kidding aside, shouldn't the feet and chassis be engineered properly for resonance control to begin with? Makes sense to me....

Your moniker seems to indicate that you work for Boulder Amp of Colorado. Is that correct?

Wood = okay but ceramic (pumice) foot sanding stone material is more neutral than wood if that's your preference. Ceramic replaced everything I tried, included roller feet, sorbothane, wood, vibrapods, etc., etc.

Stereophile has an excellent article titled "Bad Vibes" I don't have time to get the link.

Dumb question time for all you resonance control affictionados....

Its my understanding that everything resonanates at some frequency. By using different materiels aren't you just changing the resonance frequency? Wouldn't you need to know the frequency at which your present system was resonanating in order to select a materiel to move the resonance frequency to a frequency where it becomes less of a problem (I would guess that frequency would be one which was not being excited by other stuff in your system or room)?

Help me to understand this.

Thanks........

The last time I replied to a similar post it never made it past the moderators for some reason. Placing different materials like wood or brass under a cd player or tube equipment will alter the sound slightly at times for better or worse but are not very effective in isolating the component from the mechanical vibrations via the rack. If you look up isolation or vibration damping devices you will find that materials like polyurethane are used often. Sorbothane is just ultra soft polyurethane. As a mechanical engineer with access to vibration analysers it is easy for me to see which materials dampen vibrations and which don't but I doubt I can convince any of the serious audiophiles to give up their high dollar cones and ball bearings for something that cost a few bucks.