Dgad, why would you want to do this? I can see where you might think this will help isolate your equipment from floor-borne vibrations.
But if you do this what do you suppose will happen to the air-borne vibrations and internally-generated resonance already captured by and now inside your components?
More importantly, which of these three sources of vibrations and resonance induce the most sonic havoc?
BTW, nice system and room.
-IMO |
Hmm, sounds like a very tough engineering problem to me.
I wonder though why would you need to go to such lengths of isolation? Are you playing music at earth shattering levels that require such drastic measures? or am I missing something with your particular set-up, and am perhaps having a hard time visualizing what you wish to do?
They claim all components can benefit from isolation, but particularly a Turntable.
I have some doubt, or perhaps I should ay wonder again, if a physical spring-springs will benefit your situation, or maybe more likely be a detriment?
It sounds like a lot of weight to suspend, and there certainly would be more cost efficient ways to isolate some of the components. Some suspend Turntables from wall mounted brackets, and another method may be removing the entire system from the sound room all together, with the exception of the speakers?
One crazy thought came to mind about suspension, as I was thinking about my Chevy SUV, which has custom fitted Firestone Ride-rite Air Bags at the rear.
VPI used actual small Firestone Air Bags on their one TNT Turntable, but I am unaware of further custom sizes in these type of units that would be perhaps suitable for your personal application?
If they were made, a Air Suspension Bag could be fine tuned perhaps to accomodate odd, unbalanced loads, or a number of them could be mated together via air lines to provide balance-leveling.
Crazy thoughts, I know, but some words I can recall about Harry Weisfield from VPI once saying (perhaps in jest) how the perfect Turntable would weigh 500lbs, be made from concrete, and float on a bed of air.
Hoping some others can give you some better sound advice than I have, Mark |
not sure if this is what your looking for;Grainger Industrial supply,Mounts and vibration control, |
Rather than spend for an islation rack for $2000 or more $ I would like to use some springs to suspend the top shelf of my rack. If I knock lightly on the rack the feedback goes through to the turntable. I can use isalation feet but have a feeling springs will be less expensive & more effective. Some of the most effective isolation platforms in use utilize springs in compression between two boards. I am hoping to attain something as such. |
"If I knock lightly" - the best way to eliminate this feedback is don't knock at all! :-)
You are creating a condition that does not exist under normal user circumstances. Most of the acoustic problems from vibrations come from airborne vibrations which are not simulated by knocking, or airborne vibrations transmitted thru the floor which again are not simulated by knocking.
I'm not sure what type of TT you are using, but I have found the best isolation for both spring and unsuspended TT's to be a solid platform of materiel with little likelyhood of resonating in the higher frequencies, placed over soft materiel, like sorbothane. You can make a sandwich if you like. Supports with air bladders instead of sorbothane materiel can work quite well also. |
Springs will resonate/vibrate a lot easier than a set of vibrapods-which I can't call expensive. |
Placing a 2" thick piece of maple on top of HVAV cork sandwiches (the cork is sandwiched between rubber) works well. |
Dgad,
Calculating the resonance frequency of a spring with unknown physical properties is impossible. There is no way to predict whether the outcome will be better or worse, save by trial and error.
Springs also introduce the possibility (certainty) of lateral motion. This could have positive effects but for a TT I'd expect the net effect to be negative.
For beneath your Hyperspace I'd suggest three Stillpoints with risers and inverted risers. You can see them on the Teres website with the model 320. They worked wonders for the noise floor of my 265 and 320, with no real sonic cost in dynamics. Highly recommended for isolating a high mass table from floor/stand vibrations and dampening plinth vibrations at the same time, without allowing unwanted movement.
|
As I've learned-garnered information from others who are certainly more wise, and experienced than I am, the consensus seems to be that any type of tweak platform-material placed between the Turntable, and Rack-Stand will make a difference audibly.
Now whether that difference will be beneficial, or detrimental may vary in every single instance-application.
Hypothetical instances would be that perhaps one person notes a great improvement using a Sand Filled Base, or a Base with Air Bladders, with no detriment to clear mids, and highs. Another-others may find that the Sand Base-Air Base has perhaps ruined-or I should for a better term "Diminished" these above mentioned qualities of their Table.
There's so many things one can try without necessarily breaking the bank. If the Table isn't quite so heavy, maybe just two sheets of MDF with a cheap piece of fine bubble Bubble Wrap in between may make a notable improvement for isolation. Tennis Balls, Ball Bearings, Maple Butcher Block Bases, etc etc.
From an engineering standpoint, it seems to me that many table, and stand manufacturers seem to get a synergistic benefit-improvement with the use of sandwiching dissimilar materials. Things like Cork, Sorbothane Sheets, MDF-Stone, the material list is almost endless.
And then the final aspect can be appearance, and beauty.
Most high end systems are usually displayed-used in one's best room of the house. One crazy example might be taking a brand new VPI TNT-HRX Table, and have it sitting on four $2 Cinder Blocks from the Home Supply Yard. While the the Cinder Block may make an audible improvement, it certainly won't do much to compliment the beauty-aesthetics of a $10,000.00+ Turntable System. Mark |
Along the same vein as Markd51, you might also consider installing 3 feminine hygiene pads under each component, the rack, and each speaker.
Although it's pretty much a crapshoot for sonic improvements, the pads not only provide a clean and complimentarily contrast to most components, they also make the room smell like a cool summer breeze (a real benefit for lovers of smelly hot tube gear).
Of course this is assuming you use new pads, otherwise all bets are off.
-IMO |
To funny Stehno! When I was a kid, I ran around the house with a tampon, and a cigarette lighter, threatening everyone in the house that I was going to blow the place up! lol All the women were blushing, and my uncle just about fell on the floor, dying of laughter! Ahh, the crazy thing you do when you're a kid.
Yes though, I agree, a person with a little ingenuity, and thought, can devise very marvelous devices with next to no cash outlay.
I still haven't made my own Home Depot Sand base as of yet, but plan on doing so in the future. I figure for $20 worth of materials, and a bit of time, there's not much to lose if the project is a disaster. Mark |
Darren a simple & proven solution is bubble wrap. Get the pink / red colored antistatic type (for longevity) place a sheet flat between the entire slab and your rack top. The sealed bubbles act as isolating springs & can hold the weight because you're using an entire sheet |
I might try the bubble wrap. I am using Stillpoints under my turntable. The sound improved w. deeper bass & improved clarity. I just feel that a good isolation stand improves a system substantially. I don't want to spend hence the idea of using springs. If any of you have seen the Machina Dynamica or the Minus K they use springs to isolate. Sounded interesting if I could make my own. I agree about the dissimilar material idea & even the car tube. The bubble wrap sounds interesting in a cost perspective. I will pick some up & post my results once I get it done. My turntable w. the base from the Sound Anchor stand is over 200 lbs at least. Now to find some friends to help lift it. |
Koni racing shocks are the answer. |
I had Koni's on my car when I was a kid. They were great new but after a bit of use they softened up and were a little mushy. I always thought I should have changed my springs as well.
Take a look at the Minus K stands. They only use springs. It is amazing how effective they are based on the video. |
"Take a look at the Minus K stands. They use only springs."
Well, almost. They use combination of springs and "flexures" (beams under compression) - a technically complex isolation technique called "negative stiffness."
Once upon a time, around 8 years ago, Newport Corp. sold the Sub-Hertz Platform - also a negative stiffness isolator with Resonant Frequency circa 0.5 Hz.
Cheers,
GK at Machina Dynamica, Vibration Isolation and other stuff |
