holes in shelves.

over on pfm, there is a thread with an acrylic rack, with large central circular holes in the shelves.

does anybody know why shleves might be better with holes in them?

http://63.99.108.232/forum/showthread.php?s=&threadid=4942

 

(a) Lighter, therefore less strain on the support.

(b) Reduced surface area to keep free from dust.

(c) Enhanced aesthetic appeal (according to taste).

(d) Enhanced ventilation for components.

(e) Can possibly route cables through, thereby avoiding unsightly spaghetti out the back.

 

quadraspire reference tables have holes in them to reduce the likelihood of standing waves or vibration propogation or some such wazz.
cheers



julian

 

:ffrc:
Quadraspire should really take that and put it word-for-word in their promotional literature under "technical".

 

i take it that your not a believer then. i have to say, i thought the point of various acrylics was that they didn't really resonate anyway??? i guess that you don't think that there is any real audible advantage???

 

All solid materials resonate to some extent. The question is, where is/are the resonant frequency/ies? If below or above the normal vibrational frequencies encountered in recorded music, or those electromechanically produced in any part of the equipment, all should be well. I've no ideas how acrylics fare here. I also don't know how much effect the shape has on the resonance frequency. My vague idea was, none whatsoever, but then my last physics was done over 30 years ago, and I may be misremembering. However, I get the impression that the whole business of resonance is very much overdone, and I suspect that the use of acrylic shelves, whether or not possessed of holeyness, makes no difference whatsoever. But each to his or her own, I say.

 

Could it be cheaper?

 

Doubt it somehow - it would be cheaper to bring a solid rectilinear slab up to an appropriate standard of finish, than it would one with holes wiith curved surfaces, that also would have to be finished properly. It would ultimately depend mainly on the nature of the material and the size of the production run.

 

based on my expereince having shelves made (without holes), you have to pay by the sheet of acrylic, so it doesn't matter if you cut a bit out in the middle as you still need the same size sheet to start with.

i actually used polycarbonate, and it seems really dead. if your interested.....

http://forum.audiogon.com/cgi-bin/fr.pl?vopin&1082033741&read&3&4&

 

blakeaudio,
i attended the demo at brizzle with the dancing flower pot man swapping various bits of qs acrylic in and out. there was a subtle difference yes but nothing earth shattering and certainly nothing as big as an equivalent spend on electronics or speakers.
my stance is that yes stands make a difference but only subtle ones that don't justify the prices asked.
cheers


julian.

 

then i'm glad that i knocked mine up myself.

 

My opinion is that you can have a "star" rack, or, as I have, a more normal but solid rack plus supports under the CD (and TT if you have one), with similar results and probably cheaper...

I personally prefer heavy plywood shelves to glass, also had a large acrylic shelf made to acomodate the center spearker...

 

Is the dancing flowerpot man the chap who demo's Quadraspire...
I saw a dem once of the Quadraspire with holes cut in it against the one without. The differences were there, but I also got the feeling that the kit and music had been chosen to really point out the differences. There wasn't sufficient difference to convinvce me to spend £800 on one, there's plenty I'd rather buy with that much money.

 

do the acrylic quadraspire racks really cost 800 quid??? now obviously i didn't work out sizes, shape, etc. for resonance damping, but i'm still rather pleased with the way they look, and they do seem fairly inert.

best of all the whole rack only cost me 300 quid. (the biggest expense was actually the bolts to match the 16mm rods) if someone out there knows enough physics about sound waves, to work out where / how big the hole should be, they can be made up to order.

the cost at 50 quid per shelf, is pretty much fixed unless you want to use thicker shelves, the firm i used would do all the cutting / shaping i needed for that price. the stainless steel rods themselves only cost 6 quid each!!!

 

The ones I saw were wood I think, and a couple of years ago they were £750 as far as I can remember. They were dear for what they were for sure, but then all stands seem to be on the pricey side.

 

is that porn on your telly lowrider?

if so I might have to tell on you to the admin

 

:ffrc: :ffrc: :ffrc: :ffrc: :ffrc:

Michaelab, the admin, took that picture...