Wood blocks underneath components?? snake oil?

Not snake oil.

There are three materials people use: woods, stones and synthetics. What I have learned is that I like wood - mostly myrtle but lets not overlook ebony and maple. I find that metal cones, blocks etc that sound gawd awful when placed on stone (so component, device, base) sound just dandy when placed on wood platforms.

The most cost effective tweak I use are a set of three myrtle wood blocks between an amp and my rack shelf which is basically some kind of stone.

Stone in my (limited) experience is a fine damper - great for mass loading from the top.

Synthetics are all over the place - there are so many kinds. Generally whether they be Polys, Vibrapods, or Isonodes they work to either stone or wood though IMHO they sound better touching wood.

YMMV

You know, its quite a list and there are lots of things available to address virtually every step of the signal chain from the wall to the ear. I just started writing stuff down and its pretty amazing how much there is...

Cones and spikes for draining the vibration out from the chassis whatever the source

Rubber/sorbothane like substances for isolating the chassis from sources of vibration

Rubber/sorbothane materials for damping cable ends which are said to be microphonic

Things like BlueTack for coupling component and base (esp speakers on stands) to minimize vibrations - some of Herbies stuff fits here

Dynamat and other damping materials to put inside the chassis or enclosure particularly on long metal or wood spans to absorb vibration - Verastarr also has a cool material

Other damping materials for use specifically on tubes to drain and isolate them - includes brass, Herbie stuff, titanium and ceramics

Specialized damping/absorbent materials like EMI shielding tape from 3M and Stillpoint ERS sheets

High tech wall receptacle cover plates and plugs by companies like Oyaide that seek to eliminate structural born vibration from affecting the flow of electrons. Adding to this is the use of ceramic and wood devices to lift cables from the floor where they can be affected by structural vibration, static and the family cat. Consider too that power conditioner manufacturers all recommend isolating their units with cones and bases...

Beyond the spikes and cones that come between object and surface are a whole class of vibration absorbing isolating devices including granite, wood (typically maple), sand, inner tubes and composite materials by companies like Symposium, PolyCrystal and Silent Running which uses acoustic damping techniques derived from those used aboard nuclear subs.

Then you come to the whole subject of the surface that the component sits on - which includes the subject of stands. The Mapleshade Samson and the Grand Prizx Monaco are two that point at the range of possible solutions

In addition there are speaker manufacturers like Green Mountain and NOrh working with cast marble and similar stone-like materials who seek to eliminate vibration by making a container that doesn't vibrate.

Add to that the use of granite, brass and other dense materials for mass loading from the top and of course the irresistible Mpingo dots, Shakti stones etc and you have a monument to man's ingenuity...

Which brings us to the final WAF frontier of room treatments where the waves we have so carefully formed wreak havoc in our undesigned, undamped environment - increasing the need to isolate everything from them too LOL