Turntable and Rack vibration control


Hi,
I moved from a Nouvelle Platine Verdier to a Loricraft Garrard 301. The big change with this move was that the Verdier comes with a terrific implementation of pneumatic suspension feet which kept the TT almost floating and hence great isolation from vibration. The result was always a noise/grain free playback and super clean backgrounds. With the Garrard, the plinth is typical custom made stacked birch ply with standard steel cones as footers. When placed directly on the rack the background is noisy, the images muddle up and overall music is not well sorted.

I do not expect the Garrard to be as quiet as the Verdier but I know it should not be this noisy either. In fact the Verdier also sounded noisy when I placed it directly on cones bypassing the pneumatic suspension feet. 

I use a Hutter Racktime rack which is not like an overbuilt audiophile rack. It is more like an open frame rack with lightweight supports. It is a bit like a Rega TT, not very damped or controlled. The rack has pointy steel feet which rests on brass spike plates (mine is an wooden floor). I guess this implementation is not sophisticated enough to keep away vibrations and let the TT play quietly. 

I am looking at two levels of solutions:
1. Replace the existing steel feet and brass plate with a quality vibration control footer below the rack
2. Replace the stock steel cone below the TT plinth with a better footer/platform.

I have tried Sorbothane, Squash balls kind of tweaks, while they reduce noise they slow down the music too.
I have also tried Stillpoints and Finite Elemente footers under the rack. They make the sound thin and metallic IMO. Platforms like Minus-K are too expensive so I have not considered them yet.

I am looking suggestions here, probably footers and vibration control devices that are more musically oriented yet well engineered like Shun Mook, Harmonix, SSC or something like an HRS platform ?
pani
@geoffkait

It seems you have not used the free App, "iSeismometer" yet; try it you’ll love the app. I suspect your math is not correct about accelerometer, app and its effectiveness. You may try other apps (not free) and they will even tell you frequency.
Post removed 
    Pani?, There "is" actually a scientific way of calculating what in general you would need for a plinth. And they are not just for vibration. Just as your turntable woe's probably aren't simply due to simple seismic vibration. And if you have a flooring problem, that can only exacerbate things. What kind of rack system are you using? A bad rack can amplify small problems also. I recently bought a VTI BL304 with isolation between every shelf and you can fill the legs with sand or shot for mass loading depending upon what you are trying to do. It works and It looks quite nice as well.
    I've been experimenting with not only isolation but damping "not just vibrations, though I do with a laser accelerometer." and insulating. Also filtering and field barriers for awhile now.
    A wood plinth will help but a hybrid plinth is even better. Utilizing layers of protection against all kinds of unwanted distortions. Brass of certain types, "en mass" can clear your turntable of outside free harmonic resonances between 5K and 6.5K. Iron Ferrite cores, sheets and plates can have a role as well with getting rid of HF trash as can Corian and Acrylic.
    And in the end it's all subjective to the sound you want to tune your system too! I recently made a plinth from "Leopard" wood which is 49% more dense than Red Oak. And all that Jazz about maple always being the best wood to use went right out the window.
     If you'd like to learn a bit more I can steer you towards a few things. Try looking up "Parasitic modes of vibration" and their effects on amplification. This effects everything from your cartridge's tip all the way down the sound path to the output stage of your amplifier and beyond. All this according to the studies I've read about JUST, "Parasitic modes of vibration"!
Although this may not work for you - it's worth researching -  

I recently added 4 tall soft tenderfoot isolation blocks from herbies audio lab under the 4 corners of the plinth  -  as well as adding some NBneutralizer gliders under my mapleshade 5 shelf rack - for a heavily modified Linn LP12 - and I'm very happy with the results - I replaced 4 stillpoint mini's and have started using many of their other products throughout my system for vibration control 

I beleive there's a good forum dor their product on audio circle with many questions answered that somerimes don't result in pushing their own product and I've been very happy with every and any isolation product I've bought from them -  very reasonably priced - knowledgeable staff and great service -  90 day return policy on all items - so apart from shipping costs - you've got nothing to loose 
My footers are excellent isolators and will restore your image stability and black backgrounds. The "Record Enhancer" will further quiet things and aid dynamic contrast. 
https://www.anvilturntables.com/
I have a SOTA Cosmos turntable which was very sensitive to footfalls in my room - carpeted with a wooden floor underlayment.  I too tried spikes and squash balls with no real improvement in sound or isolation.  I went with the Symposium Segue ISO platform and Rollerblock Jr footers.  I can now walk around the room without skipping the record, and the sound is more controlled.  You can try the platform without the footers to see the effect of each separately.  Also, this is not a crazy expensive option like HRS.  Good luck!
Post removed 

haroon
Proof is in the Pudding!

Download free App, "iSeismometer" (three axis sensitivity), put your smartphone on turntable platter and check out different turntables, racks and isolation schemes. Play loud music, use subwoofer, bang around with your foot to simulate footfalls; see the results for yourself. You’ll be surprised to find out what really works and what is just a myth.

One problem I can think of for most if not all "seismometer" apps downloadable to mobile devices is that they rely on the accelerometer inherent in mobile devices to determine accelerations, thus determine "seismic energy" as presented on the Richter Scale which as fate would have it is energy based but not frequency based. Therefore results using sesimometer apps can be misleading, or not helpful, especially in light of the fact that almost all isolation devices have resonant frequencies of around 2.5 or 3 Hz - if they’re lucky. So, actual isolation doesn’t kick in at all until frequency gets up around say 5 or 6 Hz and doesn’t become significant until around 20 Hz, obeying a low pass filter characteristic. Which is the usual range of "seismic vibrations."  0 Hz to 20 Hz - I.e., microseismic vibration. So, in fact, you might not be able to determine the effectiveness of a given isolation device - even though it is audibly effective.

Thus, the proof may or may not be in the pudding.
I have Townshend speaker bars under the speakers with great effect. You should try it also. Not so expensive and very effective (under Analysis Audio Epsilon). Concrete floor.
I just managed to borrow a set of Townshend Seismic pods under the plinth. The sound is totally in a different level. The grainy, noisy background is 90% gone and what I am hearing is a very open airy and free sound. That is with the deck plugged directly into the wall through a basic $50 power cord, so no electrical isolation yet. Whether it is the final solution or not is yet to be seen but it definitely confirms that isolation is the problem, not the deck itself. At least some breakthrough!

Great idea of the glass marbles and bowls, Geoff. Better than the wooden egg holder or metal concave drawer pulls DIYer’s have been using. If one likes the result, the professionally made roller bearings can then be purchased, for even greater isolation.
I would first try to take the table off the rack and put it on some amp stand with metal cones or even simpler to put the table on a 2"-3" maple platform with cones under it. May not be convinient though and sure may not work. I have Nottingham sitting on 3" maple block with Boston Audio graphite tuneblocks under the block on the floor, the wooden floor in an apartment. I wouldn't want to dance or jump near it but walking is fine, and everything sounds right to me.
Proof is in the Pudding!

Download free App, "iSeismometer" (three axis sensitivity), put your smartphone on turntable platter and check out different turntables, racks and isolation schemes. Play loud music, use subwoofer, bang around with your foot to simulate footfalls; see the results for yourself. You’ll be surprised to find out what really works and what is just a myth.

Lightweight JA Michell Gyro SE (spring isolation) proved isolated while, Pro-Ject Xtension 10 Evolution (magnetic decoupling feet, 22 kg weight...bla bla bla ) was disappointing.
Till now I have tried to keep things simple with my garrard by using a good multi-layer birch ply plinth and using some cones to rest it on the rack. But it is now getting painfully clear that this is not a very well-sorted system. The noise floor is high, the images are grainy, the air and tranquility is missing. When I tried some softer footers, it did wonders to the sound by bringing back the air and lowering the noise floor, just that it was again not a full proof solution.
This suggests that the plinth thus created was not dead- and may have been imparting vibration coming from the stand. I say this because the soft footers helped, which suggests that they are isolating from the vibration source.

This is why a massive platform is helpful- it can be isolated from the stand if need be by the squishies and then the 'table hard-coupled to the platform. But that only works if the platform really can sink the air-borne vibration away from the 'table.
@pani- you said "When I tried some softer footers, it did wonders to the sound by bringing back the air and lowering the noise floor, just that it was again not a full proof solution."

What is missing, in your estimation, to reach the 'full proof solution"?

I would think some of the 301 users with various plinth set ups ought to be more help to you. 

Bill Hart (f/k/a Whart) 
Here’s a little trick with marbles. You need three large size glass marbles and three glass or ceramic shallow bowls. The ones that are used as bases for those small incense candles are perfect. Then all you need is a glass or ceramic top plate which is placed directly onto the three marbles. Then balance everything with the component sitting on the top plate so the marbles are centered in their bowls/cups but free to move in any horizontal direction. For this to work correctly there can be no cables pulling on the top plate, etc. so the top plate and component are free to move very easily.

Thanks guys,
I need to clarify few things. My floor is concrete but with wooden parqueting on top, so there are no foot fall problems.

I am just looking for a good vibration control for quieter playback. One of the achilles heel of using turntables like Garrard is one is on his own to handle isolation of the TT. The plinth is mostly any of the small DIY outfit and there is no scientific method being used to create a plinth or platform for the Garrard to be hooked on. It is quite unlike a TT like Technics SP10 or say a VPI where all these things are done up for you at the factory so it can be played back right out of the box. 

Till now I have tried to keep things simple with my garrard by using a good multi-layer birch ply plinth and using some cones to rest it on the rack. But it is now getting painfully clear that this is not a very well-sorted system. The noise floor is high, the images are grainy, the air and tranquility is missing. When I tried some softer footers, it did wonders to the sound by bringing back the air and lowering the noise floor, just that it was again not a full proof solution.

I wonder if I should get something like an HRS platform which is scientifically designed and as is a complete solution of sorts. Suggestions ?
I may be wrong, but @pani is trying to walk a fine line here- too much cushion and he loses the immediacy that these tables are known for (and the reason he presumably switched from the Platine Verdier, which is highly regarded table). I can’t really extrapolate my experience because I use a very high mass turntable, but I was bedeviled by a springy wooden floor when I lived in New York and wound up with another historic house in Austin (which actually has nice sound for reasons that go beyond this thread). Initially, I had a Finite Elemente stand for the table, but it didn’t do a very good job at isolating footfalls (I’m not sure it was intended to); I eventually had an HRS platform made for the table, and that still needed more help to fully isolate the table- using these big chunks of sorbothane under the legs of heavy mahogany antique prayer table/HRS platform/turntable.
When I moved, I didn’t have the luxury of such space (that prayer table was easily 10 feet long and heavier than XXXX).
I kept the HRS and did buy the big Minus K. It certainly solves any footfall problems. I know that @pani said he doesn’t want to get that spendy. For what it is worth, I reinforced the floor in the area when the front end gear is located- using double sheets of marine plywood, mass loaded vinyl sandwiched in between and topped with a piece of barn stall mat- the stuff you see in gym weight rooms. It isn’t springy, but it will take some punishment.
The table is on a steel welded frame supplied by Minus K- that frame was actually pretty cheap- under a grand, with a nice phenolic table top, that can be bought separately.
I think part of the trick with these things is to load them near their maximum, and perhaps that’s how @pani can straddle the line between too soft and no effective isolation. The Newport products look fairly cost effective.
I have no doubt that these lab style isolation devices change the sound of the table. But, in my case, it was a choice between that or not using this table (too heavy to wall mount effectively-- I even had a structural engineer here at one point for other work and he wished me luck).
Hope you get it sorted. If Ralph’s high mass solution works on an old wooden floor, perhaps you don’t have to go to these lengths. But, without the Minus K, it was still a lot of work to immunize my table from footfalls without such a device when I had it set up in back in NY.
I think Minus K isolation would help tremendously, not cheat but very effective 
and no compressor needed.


I also disagree about the EAR stuff. Very "weird" sounding. It looks like such good material, too. Oh, well, at least I tried. C’est la vie.
Actually granite won’t resonate or ring if it’s thick enough under normal conditions unless struck with a hammer or wrench. So my advice is don’t strike it with a hammer or wrench while music is playing and you’ll be alright. And if the granite slab is up on springs so much the better since the granite will then be isolated 99.99% from anything from the floor that could possibly make it ring. Besides the resistance to bending forces outweigh any risk of ringing. That's why the big boys like Newport and TMC use granite slabs on their uber expensive isolation platforms. 

If you plan to use a slab of granite or hardwood, the problem you are up against is that the material does have a resonant signature even if 6 inches thick. This is why the platforms I have are composed of a sandwich that also employs a steel part. That makes the structure very stable (much harder to shatter) and the steel robs energy from the other materials as they do from it, creating an anti-resonant structure. Add to that the constrained damping layer (material available from EAR, a well-known damping materials supplier) and then you have a much more neutral damping mechanism.
Granite and cones is a little bit different story than a rigid rack. In the case of granite or say bluestone, it’s less expensive sibling, it’s really all about stiffness and harness, which are more desirable attributes than rigidity for isolation. You know, hardness for speed of dissipating energy from the system and the (stiff) granite slab to isolate against bending forces. There is also inertia benefit due to sheer mass of granite slab. Never take anything for granite. To improve upon the granite and cones place another slab of granite on top of springs on top of the first slab of granite, completing the Trifecta!

I wonder if the TT sits on a granite stone with a set of metal cones between them, wouldnt it cause the sound to harden up ? I mean, wouldnt the vibrations that reflects back from granite would also make things harder and harsher ?
I agree with Glen. Granite and metal cones. Rigidity is where it's at with a Garrard. I too tried softer items on the platform and I could tell the difference between oak/cinder/brick/concrete/granite with granite being superior.

@dlcockrum  don't feel too bad, the UltraResolution Technology platforms were not cheap when they were in production...
Thanks for the helpful reply Ralph. Looks like I am once again back to drooling over the $$$ Symposium Ultra platform for my TNT.

Dave
pani, I believe the 'correct" model is the one that is intended for the weight of your table, as well as it's size, of course.
Any tips on/sources for material and construction techniques of your TT platform that you will share? I use a similar Sound Anchors stand coupled to a concrete slab with cones.
Sadly the platforms are no longer made (UltraResolution Technology); the marble is a special grade as is the steel alloy. The marble is Italian and an inch and a half thick, with 3/4" of constrained damping material (used in submarines and the like to silence the hull) and then 1/2" plate steel on the bottom. The three layers are held together by a special glue, applied under pressure to prevent air being trapped in the sandwich.
are you on concrete below the rack or the flooring?
No- its hardwood, in a house that is over 100 years old.

@pani - it may not be a complete solution, but reinforcing a wooden floor can help. 
@atmasphere - are you on concrete below the rack or the flooring?
Hi Ralph,

Any tips on/sources for material and construction techniques of your TT platform that you will share? I use a similar Sound Anchors stand coupled to a concrete slab with cones.

Thanks,
Dave
My 'table sits upon a platform that is a sandwich of marble, military constrained damping and steel. Its pretty dead.

That in turn sits on a custom Sound Anchors stand that is sand-filled. The stand is built to accommodate not only the platform and turntable, but also an identical platform on which my preamp resides. The stand has 3 additional shelves for other gear.

The stand in turn rests on a set of Aurios Pro bearings, which relieve side to side motion and vibration. Prior to this footfalls were a problem; the bearings solved that.

At this point I can play the system as loud as I want and there is no hint of strain at any level up to about 112 db (measured) at which point my amps are clipping. That's pretty loud! -yet the system remains relaxed, (apparently) at any volume. Its worth a lot to insure that the front end of the system is not subject to vibration!

Thanks to Raul I learned about ''Pneumatic footers '' from Technics.

I use the AT 636 version for my Technics SL 1000,mk2 (Obsidian

plinth) which was provided with mediocre suspension. There is

even a bigger version for the very heavy TT's which Raul uses .

I would ask Foxtan ( foxtan@netvigator.com) if he has ''some''

in stock. As far as I know ''the best there are''.

Thanks guys. I will try to get a demo of Townshend seismic pods. 
Are there any specific model of Newport and Vibraplane platforms that would suit a TT installation ?
For any turntable without a spring suspension, the Townshend Audio Seismic Pod is a great way to isolate the table from whatever structure it sits upon. Even better are the MinusK and Newport microscope platforms, but at a cost of over $2k, more than the price of many people's record players.
Racks per se can and do exacerbate structureborne vibration thus it makes more sense to skip the rack entirely and place the component of turntable whatever direction on a competent isolation stand on the floor, of course paying attention to how the component or TT is interfaced to the isolation stand and how the isolation stand is interfaced to the floor, preferably with extreme hardness cones. On the grand scale of things even tempered steel is not nearly as hard as say the special ceramic ones.
Symposium Ultra Stealth top I'm using this under my TW AC3 with all BN upgrades with wonderful results.If you want the best this is the way to go good luck.

I also have a Garrard 301 in a custom bamboo plinth and i found if you put anything under it that was squishy you would lose focus. the best solution I've got so far is a sturdy three legged stand with 165lb slab of granite on top then the table, sitting on 3 sharp steel cones. this keeps the focus but takes away 98% of the noise, bar hitting the whole assembly with hammer.  I tried sorbathane, and vibro pods and various other inexpensive types of isolation and in the end took another members advice and tried just the steel cones and they seem to be the best over all. I would like to try some of the more expensive footers out there that incorporate a cone and some mild isolation or bearing point to see If they don't muddy up the focus but give a little more isolation.

I also came from a fully suspended isolated table (Oracle Delphi mk4) and it was hard to get it right buy once you do you wont look back.