Shelf Material

The same shelf and devices will not have the same sound on different components. There are a lot of variables such as stock feet, cones, pods , etc., as well as the shelf (or layers of shelves and isolators) and also included into the equation is the specific component that you are isolating. My layer for my CD player is 3/4" Persimmon (the cabinet itself), Vibrapods, 3/4" MDF, stock feet on CAL Icon II and it sounds great. The cabinet construction as well as it's location from the speakers must influence the sound as well. I have also used 1" thick marble in the equation and found it to be too bright though a friend preferred that sound, probably because the setup sounded more like his Marantz 67 Mk II player which was his reference and taste. I once added stick on floor tiles to the bottom of an extended "plastic" shelf with good results (to me) and the tiles were not visible unless you were laying on the floor. I think that it is all up to individual tailoring for each component, and when taking into consideration individual taste, that there is no answer. I can even imagine in some cases that added resonance may even improve the sound depending on what the sound is that one is looking for.

My thoughts are that you want a shelf to be dead rather than resonant, but that it released its energy very quickly. Dead means the least effect on tonality - ie. no resonant peaks. Releasing its energy quickly means no perceived slowing of the music. I suspect that engineering-wise, getting these two things at the same time is very difficult, if not impossible, hence the difficulty I am having getting something that sounds right. I concur with all of the above posts to some degree, but think the most fruitful approach may be to get a shelf that releases its energy quickly - ie. is light and rigid - and use some form of damping that does not add weight, and hence energy storage. This aligns with the suggestions from Dekay and Vantageaudio. So I will work on that avenue I think. Perhaps two layers of 6mm perspex bonded together - but perpexes rigidity:weight ratio is not great. Perhaps Corian is worth investigating. Any ideas? Of course Dekay is right that the exact answer each time is equipment dependent, but the general strategy ought to have some consistency in my mind. Thanks for the ideas so far.

If you can get two pieces of perspex made up similar to a double-glazed window unit with the air gap evacuated and replaced with an inert gas, this may give you the rigidity and damping/energy release properties you are looking for. If you use Corian then in our experience there is no need to "layer" this material, but use some other material to frame the Corian to vary the damping/energy release properties (you can experiment with large section rubber "o-ring" material set into grooves in the Corian) but this gets expensive! Richard, vantageaudio.com

Redkiwi, Try checking out products that meet exactly the rigid/low mass/fast dissipation isolation philosophies you are looking for at www.neuanceaudio.com(my company) or www.cetech.co.uk(a respected competitor)as well as the RATA/Torlyte of Russ Andrews,UK(the man that wrote the book on low mass supports).Each has an unique manner in which resonant energies are controlled but all do so very effectively without destroying pace, rhythm and timing.Bladder devices have the disadvantage of poor location in space on a microscopic level and thus present new problems for turntables and digital reading mechanisms such as transports and cdp's. Cetech uses a carbon graphite/aluminum honeycomb composite for fast evacuation, while Torlyte is of low energy storage and internally damped.Neuance is a low mass decoupled monocoque of via constrained layer principles with a high ceramic content and internally damped.I firmly believe that any one of these products will satisfy your needs and tastes. Best, Ken Lyon GreaterRanges/Neuance

Wow, those last two posts sound on the right track to me - I will check them out. Many thanks to all that posted.