I have done extensive research on isolation platforms and with help from the Audiogon community plus many hours of listening. Its not scientific and I did not measure results but here it goes. I have tried MDF board, Granite with both and alone and cork and or neoprene rubber and truck bed material as sandwich material. Granite and marble are beautiful and mass loading. It would probably be OK for a suspension loaded TT but not as good a choice for a mass loaded TT like mine. I finally invested in a 4 inch maple slab and 4 cork rubber sandwich supports that is common in industrial machine dampening. Its better and doesn't give the sound as much detail. With detail. =harshness. Its the best I have found. With less edginess and no harshness but more neutral detail. You can use 2 MDF boards which come close. Ok, if you want the absolute best for an expensive TT get an electron microscope isolation device which costs in the thousands. You could get one for a much cheaper TT but at that point you should just invest more in a TT for more bang for the buck. I think thats what Michael Fremers 100k plus Caliburn TT comes with. Look at one of his videos. The other very low cost option is a sand box. I heard a TT in one before and it sounded great but that was a 30k Clearaudio TT. I almost went with that. I thought about suspending it from the ceiling but mine is 80 lbs. I hope this helps!
You can either buy a MinusK platform (what Michael Fremer uses) or if you are clever make a hanging shelf for your table by hanging a shelf from all four corners with springs chosen to produce a resonance frequency of less than 3 Hz fully loaded. Look at the SME 30/2 and the Sota Millennium. This is a much more stable solution than placing a shelf on springs. You can dampen the springs by stuffing them with foam. There is no other way to completely isolate a turntable. Mass and heavy shelves do not work. Environmental rumble and footfalls will make it right through. Sota owners are notorious for striking their turntables with hammers while playing without and sonic effect. This is where it all began. The only thing wrong with this video is the dismissal of anti skate. https://www.youtube.com/watch?v=1rgK0YMsJXM This is a must see for anyone interested in turntables.
i use an active system under one of my turntables (you can see pictures on my system page), the Taiko Tana system, which includes the Herzan TS-140. but it does require a turntable that has zero self noise to be effective. so it won’t work for many turntables.
another great choice is the Stacore platform; which does not have the balancing issues of the Minus K. it takes the Vibraplane idea and puts it on Steroids.
i have 4 turntables; one of which is on the active system. i would choose the Stacore for the others if i could spend the money. here is a link to the North American importer.
Actually, regarding hammers, IIRC the first ad to show a hammer blow on a turntable was for the original AR turntable. These were in printed ads, so there was no immediate confirmation of isolation. I think the dealers were encouraged to strike them while playing.
I find a sand-box together with 4 handballs as in some VIP TNT TTs to be quite effective. The handballs, though, have to be changed about every 5 years. Anyone can suspend with hand (or squash) balls by simply drilling out dimples in wood as resting places for the balls. Remember Ginko?
Since you're into DIY and value you might want to try my approach. You've already come pretty close and have a lot of what you need. https://systems.audiogon.com/systems/8367
You're right about granite and the tradeoffs with materials between detail and harshness. Its hard to tell by just my system pics but the rack is solid concrete with a sand bed cast into it. The granite is on the sand bed which damps a lot of the ringing and greatly reduces the glare and hardness while leaving all the detail.
The next step is springs between the granite and the turntable. The springs do need to be tuned to the mass of your component/shelf system, but once they are the sound is amazing! Even more detail- a LOT more detail! - but without the glare and hardness. You get all the great mass loading benefits of granite without the glare and with even greater detail.
There's a fairly recent thread started by (if I remember right) noromance about the Nobsound springs. These things are a total bargain and I would think would be right up your alley.
Sorry, the MinusK is better than all of them. The reason is that it's horizontal resonance is just as low as it's vertical resonance. In other words you can hit your rack on the SIDE with a hammer and it will not bother the turntable. Yes, it is a bit more touchy to set up but once it is you can forget about it. You could always just buy a Dohmann turntable with the MinusK ready to go. The MinusK negative stiffness design is said to be better than any active device in terms of isolation. Millercarbon, if you want to do it right you need to start working on your hanging turntable platform as described above. If you get it right it will work better than anything you are doing now. Promise:) Mike L, The Stacore has little if any lateral compliance plus you need to keep it pumped up. The MinusK requires none of this. Both it's horizontal and vertical resonance are less than 2 Hz. They also make a low profile version now which elevates the turntable 2-3 inches only. The only real downside I can see is that the platform is ordered based on turntable weight. If you were to change turntables it might not work.
In thinking about it, for $5000 I would build a hanging platform. $5K buys a lot of springs. Think MC. When your not playing music you can use it as a trampoline:)
Well see cost is a factor. As big an improvement as the Special K would surely be its getting well into Soundsmith strain gauge money. It might be good but I doubt its that good. My whole rack on the other hand was under $300, including the granite which was about $150 delivered. The sad news is I have more wanted components than money, more projects than time, and so must pick and choose very carefully. Its on the list. But its a long list.
That is the way it goes with most of us MC. We have to prioritize. Sounds like a good combination @ bkeske. The Sota is a joy to use. There is no turntable regardless of price that is as nice to use. You can rest your hand on it while Q ing without any ill effect. Jump up and down, make funny faces, hit it with a hammer. Nothing gets through to the cartridge. This includes a myriad of noises and rumble out in the environment. @slaw, it is a video that every turntable lover should watch. I pull it out at every opportunity.
If you're serious you'll do what my friend did when he built his house. He poured a separate foundation for a column that goes through his floor without making contact with the floor. So the TT sits on its own separate foundation.
Gone, that does not work entirely. It will stop footfall problems but it will not stop environmental rumble. As an example, the loaded dump truck driving down the street will get through just fine. Townsend-audio, a little long in the tooth but no argument here. The only addition I care to make is that the only device that needs this kind of isolation is the turntable. If vibration affects electronics our F22 Raptor will be in big trouble.
I guess I stepped on your toes townsend-audio. I just visited your site. Your seismic platform may be a reasonable solution for a turntable. It does place the load on top of the springs (compression) rather than hanging the load from the springs (extension) which is more stable. But, I noticed you springs have a large diameter which might help to stabilize them. I am certain that it is much less expensive than a MinusK platform making it a reasonable choice for the budget minded. Questions! How much does one cost and how are you damping the springs?
Antigrunge2, again that might address footfall problems but it will not isolate the turntable from environmental rumble. I would prefer a good isolation platform over the wall shelf. Fuzztone, another happy Sota owner! Where do ball bearings come into this?
Nothing seems to bother my 1200G...it weighs about 50lbs by itself. It sits on a solid oak rack that also has hundreds of pounds of LPs in the lower section.
Before that it was on a cheap glass and aluminum IKEA rack. Never had an issue with it on that either.
But for me, other acoustical issues need to be resolved before I get to how a TT platform 'sounds'.
I am currently waiting for the construction of my Silent Running Audio (SRA) VR platform for my Woodsong Garrard 301. The TT sits atop a decent Polycrystal rack. Recommended as vital to his system by Ralph Karsten. Now suffering from footfalls. Hoping for good results. Anyone using a similar platform? What are the effects?
living in a house with brick double walls and a basement I am not sure what environmental rumble you might be referring to. If it existed I should get a feedback loop between speakers and cartridge when set on a record.
@mijostyn, to have the design of the Townshend Seismic Pod (the active element in all the Townshend isolation products) explained, and to see it demonstrated, watch Max Townshend's videos on YouTube. Once on YouTube, a simple search of his name will bring them up. The video of Max at a table with a projector is the best one.
No antigrunge2. It is not a feedback situation. If you put an oscilloscope on the output of your phono stage and place the stylus down on a record with the turntable off without adequate isolation you will see an varistey is low intensity low frequency signals that you will not see on a suspended table. Watch this all the way through. https://www.youtube.com/watch?v=1rgK0YMsJXM
bdp24, The Townsend Seismic Pods are dampened compression springs of various spring rates. They can certainly be useful under certain circumstances. You can place them under your turntable and if you order the right ones should be able to get your resonance frequency below 3 Hz. It might be a little wobbly but I have not used them so I really do not know. Certainly with an unsuspended table they should make an improvement. I do believe Townsend makes a platform which would be better to use under a turntable. It is my personal belief and experience that putting springs under amplifiers and speakers is not beneficial. My system certainly does not benefit from this.
I built one step one go to granite shop pick an appropriate sized scrap piece, Step 2 picked up a 1 inch thick sheet of MDF, Step 3 cut up an old yoga mat and glued it between the properly sized marble and MDF piece. Clamped them together and let the silicone glue dry. Total cost about $20 in materials and a couple hours of my time. It works great.
I have had Isopads for a quite some time and last night decided to use them under my VPI Classic 1. The difference was VERY noticeable. Cheap and easy tweek.
I have the best turntable isolation. The TT's (and electronics) are in a different room. no vibration at all. It was my laundry room, and has a dedicated 30 amp outlet... actually two from the old dryer outlet, which is now a duplex 110. It cost well under $5.
1 1/8" granite glued to 1/8" blue vibration damping material glued to 1/2" ground steel plate ... all sitting on 4 - Townshend Seismic Pods which are adjustable for leveling turntable. This constrained layer platform on top of damped spring Seismic Pods works beautiful with my Brinkmann Balance.
@townsend-audio, I'm afraid that would be difficult to do. I do not even have 1/4" worth of room. If you look at my system page you will understand. As for the subwoofers, I have four of them and each one weighs almost $250 lb. That is a lot of jing for an experiment.
You must have a verified phone number and physical address in order to post in the Audiogon Forums. Please return to Audiogon.com and complete this step. If you have any questions please contact Support.
