TW Raven Acustic AC Owners

Isanchez,
Do you know what cyclic loadings are?....I doubt it as you fail to answer the question on your qualifications?
And prey tell what 'cyclic loadings' have to do with a cantilevered wall shelf?
Just to dispel your other inaccuracies for any readers who think you actually may know of what you speak.........any 'not so well executed' wall shelf (and can you please describe what you mean by this as I can't even imagine?), will beat hands down, any WELL executed floor mounted stand!

As with ANY turntable (unsuspended OR suspended)......placing on a cantilevered wall-mounted shelf is hard to beat.
The Raven AC is heavy so that a masonry wall is recommended or really rigid bolting directly to studs in a plasterboard is necessary.
To mount on a rack sitting on the floor.....you need to spend $20,000 like the Continuum Audio Caliburn stand for a similar result to wall mounting.

Mount the TT on a shelf firmly cantilevered from the wall.
Sound is transmitted it 2 basic ways:
AIR-BOURNE
STRUCTURE-BOURNE
90% of audiophiles mount their TTs on racks sitting on the floor.
This is a disaster for both types of transmission.
Even a concrete floor (which is not generally bouncing around like a timber-framed one) is a great transmitter of sound, so that any rack sitting on the floor is receiving BOTH types of transmission.
This is why Continuum Audio Labs create a rack for their Caliburn that costs $25,000. That's how much technology is required to overcome this basic problem of physics.
When you cantilever off a wall, you are disconnected from the floor (USA stud frame tradition can often short-circuit this advantage).
The materials to fix to the wall, project from the wall and form the shelf for support, generally act to physically 'de-couple' the shelf from the wall.
Thus all or most STRUCTURE-BORNE and AIR-BORNE sound transmission within the floors and walls are eliminated.
The only transmission to now worry about, is the AIR-BORNE transmission directly into the supporting shelf (and here is where Jon's granite shelf is NOT a good idea.
Granite rings like a bell and transmits sound deliciously throughout many audible frequencies without much absorption or dampening. Timber is a better insulator and dampener.
However it may be academic because all one has to do is DE-COUPLE the turntable from the supporting shelf to eliminate the transmission of this air-bourne absorbed sound.
Stillpoint cones with ceramic balls is a good way and there are many others.
Then the only sound transmission to worry about is the AIRBOURNE sound which the TT base and platter are able to absorb THEMSELVES.
This is where the turntable designer earns his crust with the elimination, absorption and dissipation of this air-bourne feedback setting his TT apart from the rest.
Of course the ability of the tonearm and cartridge to absorb and dissipate this same air-bourne transmission (feedback) is equally important but the frequencies are much higher and smaller.
So the moral is......do everything possible to wall-mount your turntable.

Isanchez what is your profession?
Your talk of material fatigue displays an ignorance of structural principles.
Apart from ' metal fatigue' which can occur when metals approach their elastic limits after repeated cycling of loads, there is no material ' fatigue' in structures that I am aware of and certainly not in regards to cantilevered wall shelves.
Tightening screws and bolts has nothing to do with metal fatigue.

http://forums.avguide.com/viewtopic.php?t=3588
Please see the link above for diagrams and further explanations about AIR-BORNE and STRUCTURE-BORNE sound propagation.
Unfortunately, some posters without architectural, structural or acoustic qualifications presume to post fallacies.
If the brackets and bolts are sufficiently sized to accommodate the loads imposed, there will be no ' material fatigue' over time just as there is none in properly designed floor or roof fixing brackets and bolts.
Insulation placed in stud wall construction will NOT prevent sound from traveling between rooms. At best, it will REDUCE the sound but at only certain frequencies. Those below 200 Hz will effectively pass straight through the insulation.
It is the de-coupling of the wall-mounted shelves that (as shown in my explanations) is the salient benefit.
A properly executed wall-mounted shelf will NEVER ' do more harm than good' .
The only harm I can see is ill-informed uneducated pontifications posing as scientific fact.

Dgad,
Go and police some other threads and don't tell me where to do my postings.
You might also like to re-read the posting questions and my initial answers?
There are very few on this forum who have structural and acoustic qualifications or experience so that when they read a posting which purports to contain 'facts and truths', they are liable to accept such posting at face value.
There are no down-sides to wall-mounting a turntable if the weight can be accommodated.
This is a simple fact of physics and acoustics and will never change.
To frighten people into thinking it is 'rocket science' and therefore best to take the easy route of placing the deck on a floor-mounted stand as you have chosen to do, is irresponsible advice in the quest of better analogue sound.
Mark Doehmann who designed the Caliburn floor-mounted stand which costs $25,000, agreed that at best......it equals the isolation performance of a wall-mounted shelf.
Pity that you'll never hear that?