Shelf Material

My comment that some resonance may improve the sound quality was based on the assumption that many products have been "voiced" when under the influence of a certain amount of resonance. To remove all or more realistically much/most of the resonance may in fact degrade the sound. This is hypothetical.

redwiki: you've already received some excellent advice, which i have no intention of undercutting or disparaging. in my younger days, i, as you, had a compulsion to create for myself bits of my audio system that seemed within my means, ability and understanding to produce. among these were shelves and racks for my equipment. as i've grown older and, unexpectantly, have less leisure time than i did in my younger days, i've relied less on my own abilities and more on those i judge as "experts" in whatever field is necessary to my ends at that juncture. hence, i've looked toward commercial developers of racks and the shelves that go with them. the company i've come to trust in for this aspect of my audio system is zoethecus. their shelves are top-notch and manifest the qualities your last 2 posters recommend. they are not, however, what i would call lightweight (actually, not figuretively). you can, tho, come close to replicating them. as with others, they comprise a "sandwich" of several materials. the idea is to use different "dead" materials of varying intrinsic resonances, all of very low hz., to cancel out the resonace of any single layer. i do not know the actual formulation used by zoethecus in their "z-slabs," but suspect that they include alternating layers of mdf-like pieces and absortive layers resembling sorbothane. these layers, topped off with a metallic uppermost platform that can withstand the weight of heavy "spiked" equipment, are wrapped with what i expect is a heat-activated edging that makes a tidy, handsome package. you can find these shelves alone on audiogon every so often. you might wish to buy one (or "borrow" a copy from your nz dealer) to investigate their properties. i've found nothing better for all equipment, from tt's to amps (my main amp weighs in at > 150#). in any event, i wish you good hunting. your posts are invariably among the most useful, interesting and polite among all of the "regulars" on audiogon. i hope someday to visit your island that, in my mind's eye, must be a heaven on earth. cheers.

Thanks for your kind words and advice Cornfedboy. The sad reality is that the only racks/shelves that reach these shores are of the basic variety, with the exceptions being Mana Acoustics and Townshend (and I own examples of each - most of which are in "the closet"). There are importers of cones from BDR and Polycrystal, but noone brings in the shelves. And noone brings in Zoethecus so far as I know. For example, I wanted two amp stands for my monoblocks and called around all of the better dealers in New Zealand - or at least that was what I intended, but truthfully I gave up after the first six because I was sick of explaining what an amp stand was... if you get the picture. In the end I did what every other audiofile does here - got them made. I would indeed prefer to just try and buy, but I am much less keen on importing one, only for it to end up in "the closet" - I am sure we all have one of those. Having come to this point with shelves (ie. needing to splash out and hope), I posted here hoping optimistically that there might be a concensus as to the best shelf material/product so that the chances of success could be improved. I think Albert Porter has done a lot of experimenting with vibration control, but his posts indicate he agrees pretty much with Dekay ie. that there is no universal answer. Perhaps I am being too optimistic. Anyway, I will investigate Zoethecus from here, and perhaps that is what I may end up trying. I hope you do get to New Zealand one day. I have known many Americans who have come here - some stay, some get homesick and go back. The ones that stay are adamant there is no place better. Personally I don't think it is a place to spend all one's life, but it is a wonderful place when you are a kid, when you have kids, and when you want to live a quieter life later on. In between, most of us Kiwis travel a lot and I have been forunate to visit your lucky country a number of times - picking up audio gear every time of course.

Hi Redkiwi. Found your opening remarks very interesting. I'm trying to struggle through with an old Rotel 855 while mulling new digital front end options, and am trying to reduce high frequency roughness now apparent in my new otherwise-highly-resolving system. I'm using an air bladder suspension under the CDP, and am not aware of any change in PRT, as you suggest is possible/probable. Before I try reusing my old cones, or sorbothane feet, etc., and struggle to hear changes, do any of you guys have suggestions for improving CDP isolation (esp HF grain) WITHOUT compromising rhythm?...and indeed is it true that non-rigid setups (like airbladders) risk timing anomolies? Thanks. Ernie

Only the Townshend are available in this part of the world, and they are not light compared with a light rigid shelf. I hear them as slowing things up. I am not familiar with the 855 so it is difficult to comment further on the problem you are experiencing. Currently, I use a very light and rigid chip-board shelf under my transport - the sort that is small chips of wood glued together and which includes a lot of air. It is much lighter and more rigid than particle board. It is clad with a very hard surface of compressed wood and so cones and spikes make no impression on it. I then use BDR #4 cones under the transport. In general I find that the right cone depends on the shelf being used, and that this combination works quite well. However, the reason for this post is that, although the result is fine, it is still a trade-off. It is definitely still more resonant than using a bladder product, but I prefer its more accurate pacing.