Help! Tweaking My Lovan Rack for new Big A**ed Transrotor Turntable!

BTW, FWIW...

My audio racks are located in another room down the hall, well away from the listening room, so isolating them from speaker sound isn't a big issue.  Nor is isolating from footsteps - nobody is usually walking around when I'm listening and the turntable is in it's own room.

Though 3" planks of Maple are hot right now, I myself would have some shelves made out of 19mm-3/4" 13-ply Baltic Birch plywood. You could even use two layers, with constrained-layer damping between the two. For the hollow columns of the Lovan, sand will be a more effective vibration absorber than will rice. For isolation, an alternative choice to the Symposium shelf is a set of Townshend Seismic Pods, or Seismic Platform. If you have the $ (over $2000), a serious vibration isolator is the Minus K line of products.

Long term I recommend a dedicated Sound Anchors turntable stand.  I have used one for my Galibier table (over 100 lbs) for a number of years and absolutely love it.  It puts the table at the ideal height without any wobbling whatsoever, and it brings out the best sound for my table.  I use a wood platform on the top which consists of two solid maple boards bolted together.  Cost of the SA stand runs a bit over $1000.  That may be more than you want to spend right now, but if so I recommend you not spend less money for stopgap measures like fancy shelves or footers, and instead save your money until you can buy a proper stand.  Just my opinion.

Thanks for the input, folks.

I've read that loading sand is more finicky than rice into the Lovan, especially insofar as the Lovan pipes don't have a really tight seal and something as fine as sand spills out unless you go to further lengths to seal them up.

The Townshend Seismic Pods actually look just the ticket!  They look like they'd provide the type of isolation I'm wanting (for now) and they are adjustable which would help with leveling the platform.  Only problem is I can't find dimensions for the things ANYWHERE.  Including on the manufacturer's site.  How can a manufacturer not include such obviously relevant information as the dimensions of a product that people are going to try and fit under various types of shelves and equipment????

Right, prof?! I wanted to find out how tall the Seismic Pods are, and neither the U.S. Townshend distributor nor any Townshend retailer could tell me. Lame! I just bought a used pair here on Audiogon---when they get to me I’ll post the Pods’ dimensions.

bdp24,

Oh, so YOU bought those used ones!  In my research I saw that add.

I did find someone who owned them, answering a question about their dimensions.  He said of the height:  between 65mm, and when fully compressed 40mm.

That should work for me.

Ha prof, beat ya to 'em! The set I got are rated for 8lbs. apiece, so I can try them under both my tube phono and line amps, and Townshend Rock table. If they're as good as they're supposed to be, I'll get some more---a set for the SACD player and tube pre's, at least. Sources first, then tube amplification. Some people have found them to be most beneficial under speakers, but that can get expensive if you have subs. New, a set of Pods is about $375, for it runs about $1500 for speakers and subs. I'm one quarter Irish, so you know how I feel about that ;-).

Good for you!  I'd need the higher rated ones anyway as they'll carry somewhere around 84 pounds above them.

I don't bother placing anything under the rest of my sources these days, so a one time expenditure for under the turntable (as I find it more plausible a turntable will actually benefit from a proper surface), is fine with me.

I need the next higher rated Pods for my other critical sources myself, as they weigh 47lbs (CD/SACD player) and about 50 (VPI table). Same for the power amp and speakers. But the IsoAcoustic GAIA looks interesting, too. I'm in no hurry, gonna take my time. I would love a Minus K table, but I don't want to spend the over $2k it takes to get one!

I do have similar stand ,or maybe exactly same !
i just put maple block with 3 1/2 inch thick on top chassis with some small pads on 3 frame,
The block sit perfect fit ,you can see how it look at my system here with my VPI classic with upgrade bigger feet .
block size 15x20

honeypooi,

Your rack does look similar.  Nice job on those maple blocks, love the look!

BTW,

I was originally going to purchase a frosted block of acrylic as the base on which to place the turntable.  My rational was that, while the Transrotor turntable is beautifully made, I'm not crazy about silver as an aesthetic.  So I intended to play with the reflectivity and turn it into a virtue; the acrylic bloc would have an LED light strip affixed to the back so it would glow in whatever color(s) I choose, lighting up the turntable.
(You can get such ready-made blocks online).

However, I had originally been set on some very nice turntables, for instance the VPI Prime Signature in Rosewood, because I love me some beautiful wood.  Turned out the Transrotor was just the better bargain all told in terms of what I was getting for a lower price.

But I still wanted to satisfy my desire for introducing some nice wood into the picture, hence I'm putting the turntable on a nice block of wood.
I'm also keeping the idea of lighting up the turntable with LEDs, either by placing the LED strip on an acrylic panel in front of the wood base, or hidden on a raised (about 1/2" tall) ridge at the front of the wood base.
I grabbed a Philips Hue light strip and played around; it makes the Transrotor table look quite spectacular! 

So up to this point I would have the Townshend Seismic Pods sitting on the top (thin) MDF shelf of the Lovan rack, holding up a 2" thick wood base, on which the turntable will sit.  But now I'm thinking I may add a thicker, more firm piece for the Seismic Pods to sit on: maybe a little sandwich thing like: top MDF Lovan shelf/layer of cork or something like that/granite or thicker MDF slab - and then the Pods holding up the wood base/turntable.

What a rabbit hole one can go down on this stuff!

Ended up at home depot looking around today.  All sorts of possibilities went through my mind.  For one thing, while they didn't have any granite slabs to take home, I grabbed instead some 3/4" MDF to place on top of the flimsy MDF shelf of the Lovan.  I also happened upon some thick, solid (but still squishy) various rubber matts.  Some for cars, some for workers to take their boots off on.  About 3/4" of rubber.  I wondered how those would do sandwiched between the Lovan shelf and the MDF board.  Then I remembered that some people have used foam in some sandwich constructions, and I found some nice 1/2" to 1" thick foam. They are the interlocking foam sheets (sort of like a puzzle interlock) used to make little kid's play areas crawl-worthy, or anywhere else a softer floor is needed.  They seemed to fit nicely under the MDF board, with just a bit of give. 

So I thought maybe:  Lovan mdf top shelf (thin)/layer of foam/thicker MDF board - as a sort of more solid, layered top of the shelf.  On that would stand the Townshend Seismic Pods holding up the 2" thick maple bass and turntable.

Am I nuts?

Not nuts. Just be aware that all these materials sound different, and the theory behind the layers- constrained layer damping- is to combine different materials with different resonance characteristics to arrive at a fairly neutral solution. I’m not sure acrylic is best--I have one remaining shelf from my Grand Prix racks that I bought long ago still in use- all the others were upgraded to carbon fiber, but even in that rarified club of fancy racks, they are not necessarily a favorite among some these days. On the cheap, folks seem to like the sound of maple. Granite- not so sure. I have an HRS platform that is some composite of granite with polymer damping in a billet aluminum frame- there is some know how that goes into this and I couldn’t tell you that it is better or worse than a comparably priced platform. I use it mainly because my turntable- a Kuzma XL-has no platform; it is all separate parts that stand together and weigh around 186 lbs. With the HRS underneath it, another 58+ pounds. The HRS is not really a full blown isolation platform. At least it wasn’t for me- it didn’t isolate footfalls on a wooden floor. For years, I used mass loading of a very heavy mahogany table with thick chunks of sorbothane under the mahogany table legs, and put the HRS and turntable on that, but even with all that mass, it was less than ideal. I now have a Minus K.
But before you get spendy on isolation, research some of the threads here on DIY platforms and sonic characteristics. Some of the industrial racks used for scientific equipment, used, could be a bargain. In fact, Minus K sells a nice welded steel stand with phenolic top-- like the counters in labs that don’t stain-- for under a grand. (It provides no isolation but is just a stand).
Congrats on a high mass table. I really enjoy mine. I mentioned in another thread on isolation that there is a company called Newport that makes isolation device components- depending on weight, that might be a cost effective solution. I’ve not used the Townshends but those were on my radar as well. In effect, you need a stand with a decent platform and isolation. The units that do all of that can get pricey, and might be better found used. I know there are fans of Symposium platforms here, but I’ve never used one and can’t comment on their use or application.
The DIY route is good if you know what you are doing- otherwise, you are buying supplies, and paying someone to cut and possibly, help assemble. 

I used DIY (with contractor help in cutting and assembling) out of such materials as marine grade plywood, mass loaded vinyl, green glue, and those heavy rubber stall mats. This stuff was used mainly for floor support, not turntable isolation as such. It still added up by the time I was done buying the material and paying the contractor (reasonable) to do the cutting and heavy lifting.
Sorry I’m raising more questions than I’m answering, but...

prof---While MDF is cheap and easily obtained, it’s not a very good material for a shelf. Think about it; MDF is sawdust and glue mixed together---somewhat non-resonant, but not very stiff. 13-ply Baltic Birch ply (19mm, or 3/4" thick) is very stiff, a good thing in a table platform. A couple sheets of that with constrained layer damping (such as that offered by ASC as wall damping pads) between them will make a great shelf. Or, check out the isolation platform offered by Symposium Acoustics, specifically for tables. It is a layer of foam between two sheets of stainless steel, with special springs on it’s underside. Economically priced, $349 I believe.

If you are considering Symposium products (any) I would suggest you give Peter a call at Symposium, their products all complement each other and are part of a 'system' of vibration control.  I started with 1 component a long time ago, and now I use Symposium with everything.  They bring out the best in a component's sound.

MDF-foam-MDF is not going to give you constrained layer damping, and MDF is a bad choice for audio in general, IMO.  But there are good materials for sale at Home Depot.  See if they have a cement paver that is large enough to support your TT, for one example.  Check out Adona; they may sell their excellent CLD shelves separately.  Or used.

I would use lead shot, not rice, if not sand, as a filler in your Lovan.

No disrespect but MDF is Medium density fiberboard, most speaker manufactures use it

@Prof I would recommend sending a pm to the audiotweak he is very nice man with a wealth of knowledge about vibration control. Like lewm
I have used lead shot for years in conversing with Tom, audiotweak seems micro steel spheres is the way to go, even more so than micro ceramic spheres.

Dear perfectpathtech, You wrote, "No disrespect but MDF is Medium density fiberboard, most speaker manufactures use it".  I welcome your dissent, but your statement proves what?  It proves that MDF is cheap.  Lots of turntable plinths are made of MDF, too.  MDF plinths are usually found on the lowest end turntables, in terms of cost.  Certainly MDF can be used as one layer in a CLD construction; Adona uses it that way very successfully.  But two layers of MDF separated by foam would not have any CLD property, because the foam is mushy in between two layers that have identical properties.  The foam would impede energy transfer between the two layers of MDF, at least in my opinion.

@lewm

My apology no dissent meant, I  misunderstood what you meant by MDF
Foam MDF, and no I would not consider using foam in any way for isolation or damping

Thanks for all of the input.  There's a heck of a lot of opinions for me to consider (even worse when I research threads in audiogon and other forums).

I'm still set on a nice big hunk-o-wood for the turntable to sit on, then likely the Townsend pods under that, and they would sit on...not sure.  But I did put the raw 3/4" MDF sheet I'd picked up at Home Depot, on the top of the Lovan rack, then the thinner Lovan rack on top (also tried underneath).  I have to say that just adding the thicker MDF gives me a whole lot more confidence, it feels so much more solid, than just leaving it with the stock, thin MDF top.

I went to see a local wood guy who would do the wood block.  He's done similar things for stereo gear.  I'd first asked about maple or similar hard wood.  He had maple, wall-nut, but he pointed me towards a beautiful couple pieces of Siberian Elm, which when stained would be my preference over the other woods.  I've seen that Elm, depending on the type, can be in the "soft" or "hardwood" designation.  I'm not sure where Siberian Elm lands, but he insisted this was a really hard wood, similar to maple.

Quick research says that this tree was resistant to Dutch Elm disease, but it does not dry flat if I’m reading this blog correctly. That, and its stability in retaining flatness would be a big issue in its use for a turntable platform as I read it. The durability factor seems to be less of an issue indoors: https://wunderwoods.wordpress.com/2011/12/20/siberian-elm-and-american-elm-leaders-of-the-elm-revolu...
The Janka scale rates hardness: http://www.globalspecies.org/ntaxa/838586

It doesn’t seem like a very hard wood, but I’m not sure that’s the sole factor, and you said that your wood guy claimed it was a hardwood. If you look at the ratings of the Janka scale generally, you can see what the particular rating above means in context of other woods.
Again, like everything else in this hobby, the measurements or one specification, don’t necessarily tell you how it is going to sound. Add to that the layers of different material and I think it’s even more complex- I would think you’d want something very hard on the surface facing the table bottom, some sort of polymer or deadening material like green glue and other materials from acoustic supply houses, sometimes along with mass loaded vinyl and then, perhaps a different type of wood. Others with more knowledge of acoustic properties of wood, and their combination, may be able to direct you better. Good luck.

I was in a similar spot for a while, running a 50 lbs table (Clearaudio Innovation Wood) on a Lovan Sovereign (three tiers of 7" shelves). These stacked modules are not particularly rigid, and the relatively small 3-point footprint doesn’t help on floors like mine. I filled all the tubes with lead shot, but that didn’t help at all with rigidity; it only damped the nasty metallic ringing.

The Sovereign was a poor solution for this very nice, mass-loaded table.There were definitely feedback issues, and it was very sensitive to footfalls, etc. The VTI-style stands are even flimsier. I added a Maple butcher block, which helped a bit. But honestly, I was just fighting the nature of things, and my old SOTA Star III was a more natural fit in this scenario (the spring suspension absorbed a lot of these issues).

You want something that has a rigid frame, not modules. 4-points and a larger footprint is also better. When I upgraded to the Innovation Master I knew the old Lovan would render this upgrade pointless, so I went crazy and got a Critical Mass Systems rack -- MUCH better, obviously (you can see the massive difference between these racks in my virtual system pics). But there will much better solutions than the Lovan for much less money too. As mentioned previously, some of the active isolation platform makers like Herzan will supposedly make a very nice (and rigid) custom stand for a reasonable price.

The Lovan/VTI stands are OK for digital sources and SS components.

jab, mulveling,

Thanks for the additional input.  I really appreciate it.

Having priced a custom rack, I'm still stuck for now with the Lovan until I can afford a new rack.

I'm going to have a maple butcher block made, I figure about 2 to 2 1/2".
The Townsend pods below that.

I'm still actually deciding whether to bother filling the stand with anything.    I don't really have to worry about some of the main vibration issues because my turntable is in a room well away from the listening room.  And I tend to listen when the house is quiet and no one is walking around.  So I'm not sure how much more the is to actually isolate the turntable "from."

One thing I've wondered:  Right now the Transrotor turntable is sitting on an MDF shelf.   The Transrotor has 3 shallow aluminum cone "feet" that it rests upon, which you can adjust to level the turntable.  I notice that, at least on the shiny Lovan MDF shelf, the turntable is fairly slidy - there is no grip happening between the point of the feet and the shelf.  So I'm wondering if there are any little rubber pads, or shallow cones or something that would be good to set those feet tips in - maybe to provide further isolation as well as gripping the shelf top better?

OP; Welcome to the Transrotor club. Your Fat Bob S will give you years of listening pleasure. I have a Transrotor Apollon with 3 motors and the triangle design with spiked feet going into cones with rubber feet, I think somewhat similar to yours. I too looked for wood but since the system was heavy, over 100 pounds, and large, I opted for a dedicated stand from Clearaudio, the MontBlanc. It’s really a solid beast with a plexiglas as the base, and concrete filled CNC polished stainless steel foundation. It’s more of a modern design, rather than the homey warm classic feel of wood. I have a zebra wood platform for my preamp power supply😀

My floor is basement, bamboo floor, and no vibration issues. Even with multiple subs blasting. I am a firm believer in rigid isolation with minimal bouncy isolation things for the turntable. I also highly considered the Finite Element stands due to their nice wood craftsmanship. Good luck.

Audioquest4life

Audioquest4life,

Sorry, I missed your comment.

Thanks for the welcome! Wow, the Apollon! And I thought my Transrotor table was a beast! Must be real fun.

I just received my Townshend Seismic Pods which I plan to use under the wood platform I’m having built. I had downloaded a seismic vibration measurement app, placing my iphone on my Lovan rack and then on my taller home theater rack. I must say I found it a bit alarming how much vibration was transmitted up the Lovan rack when I walked or lightly stomped near the stand - it was decidedly less on the bigger stand beside it (but that’s full of my AV gear and not suitable for my 2 channel stuff).

With that in mind, I’m looking for some more isolation. There are so many different opinions on this, ultimately I think I’m throwing together stuff that gives me my own piece of mind, without spending a million bucks. At this point I’m planning on securing the top Lovan rack shelf to it’s frame making it less tippy. Possibly filling the stand. I’m going to sit a Auralex Acoustics ISO-Tone Turntable Isolation Platform on top of the Lovan stand - it has lots of good testimonies for really fixing the type of sound transmission I spoke of. Then that will be the first base on which the Townsend pods will sit, holding the new 2 or 3 inch thick wood base for the Turntable.

I even picked up some of these isofeet:

https://www.ebay.co.uk/itm/Isofeet-by-SoundDampedSteel-Set-of-4-in-black-ROUND-80mm-diameter-/201230...

I figured I might put them under the feet of my turntable (might help make it less slippery on the wood block, as well as help isolate), or alternatively maybe I’ll put them between the floor and the points of my Lovan stand.

My instinct says that stacking suspensions and/or squishy layers can have severe unintended consequences, especially the more stuff you layer in there. Keep it limited to 1 suspension or squishy layer, and it should be a good one. I had the "Gramma" version of those Auralex for speakers, and it’s not something I’d put a high-end 50 lbs table on...too squishy, and has a very cheap feeling (and sounding) MDF/felt top board.

Securing the Lovan modules (somehow) is a good idea; man that always made me nervous as heck when I had to curve around a back corner to do cable connections. And I know the slide-y glossy shelves issue all too well. Had a girlfriend once take a tumble, glance the rack (1 had 3 modules stacked with the CA Innovation on a maple block on the top), and nearly slide the TT off. No harm done in the end, though.

But your beautiful table really deserves a rigid-framed, 4-point rack! I’d look at something like the Adona AV45G in your shoes (not the modules, the full frame). ASAP. Not too crazy priced at $1K for a 3-tier (really quite sane actually). No affiliation, and I’ve not had one myself, but I’ve seen the Adonas in use on very high-end TT setups, including a pair of ears I’ve trusted for a long time. That should help immensely, and you can still experiment with high-tech/suspension feet under the table to address the foot-falls and feedback. I should’ve done that when I got the first Innovation, or stuck with a SOTA (man that spring suspension forgives a lot).

And I just remembered that Symposium makes a platform with a small suspension in the feet, for turntables, that users seem to love. But you’ll still want a solid stand under it.

@prof, 

What makes this hobby fun is the shared interests and experiences of others to help each other out. In terms of isolation, the more rigid and robust in terms of mass your base platform is, the better it will isolate the rest of the equipment from vibrations. My experience with that method is to spike the base platform to isolation footers to your floor, tile,  carpet, bamboo, concrete, wood, or whatever. This type of isolation works extremely well especially if the base platform sits on a rigid base...non floating floors, etc. Minimal vibration transfer will occur using this method. Then, the platform on which your components sit, you can experiment with a variety of absorbers, cones, or rubber feet,in the pursuit of vibration free happiness. I for one have relied on the spiked feet platform approach, and the turntable rests on a one inch thick plexiglass with semi-rigid rubber cushions. Works fine for me. The knock on the platform test does not reveal any vibration through the turntable. Of course, my platform mass consists of nearly 300 pounds of concrete poured stainless steel columns, ala, Clearaudio, with the aforementioned spikes. The mass of your Fat Bob will aid in helping to damp any vibrations as well. At the dentist nd of the day, spiked feet to the floor is one step in the pursuit of isolating vibrations. 

On another note, if you play music extremely loud, I have not found any way to isolate high pressure air disturbances on the tonearm due to extremely loud volume, which is probably not safe for hearing anyway, LOL. Unless, you move the turntable into another room. Once you pressurize a room to cause harmonic and resonant distortions, you are in another league, haha. I have not reached that point in my new room yet! 

@mulveling,

I fully agree with this statement “But your beautiful table really deserves a rigid-framed, 4-point rack”. 

Cheers,

Audioquest4life

mulveling,

Thanks for the input.  Believe me, I'd love to get a new rack.  Unfortunately the Adona racks are too big.  I'm working with a really restricted level of space, which is one reason the small size of the Lovan has worked well for many years.  If I get rid of the Lovan it will be for a custom design rack, but as I've said, financially that's a ways off.

audioquest4life,

Fortunately my turntable is in a different room, down the hall, from the speakers so air-transmitted vibrations won't be a problem.

When you suggest spiking the rack into footers, would you be thinking of something like these?

http://herbiesaudiolab.net/spkrfeet.htm

@prof, 

Yes, exactly. Something like that should aid tremendously in your vibration mitigation strategies. Glad that you don’t have to worry about airborne transmitted vibrations either👍😀

BTW, interesting test results:

In putting away some audio boxes I re-discovered my old Auralex Subwoofer platform that I never really used. It’s a thicker-foamed version of the turntable platform. I tried a little experimenting with the Auralex and my Townsend pods, using my iphone seismic measuring app placed on various surfaces.

First, I have tried the app on top of my Lovan, where the Transrotor table is now sitting. Right now I have a 3/4" sheet of MDF sitting on top of the lovan rack, then the thinner Lovan MDF shelf, then the Turntable.

What’s interesting, maybe a bit alarming, is that when I place my iphone with the siesmic vibration measuring app on the top of the MDF shelf, and rap the other side of the shelf (that is rapping the top of the shelf to the far left of the iphone), there is impressively little transmittion occuring. The raps show a small spike, but almost no ringing.

But when I place the iphone on the turntable platter and rap the same part of the shelf, there is actually a little bit larger bump registering, with a tiny bit MORE ringing. And I would have thought all the heroic efforts at dampening with this turntable would have yielded the opposite - less vibration transmission.

Then I tried the app on various surfaces. Putting it on my kitchen granite countertops and rapping about a foot from the iphone yields very little result on the app - so little vibration transmission. Pretty solid I guess.

Then I went downstairs to our pool table, placed the iphone on the table and measured the effect of rapping the table with my knuckle about a foot away. Definitely registered some bumps. Then I put the Auralex platform on the pool table, the iphone on top, and rapped the pool table top again. Still quite a bit of vibration registering. Hmm. (I found the same when I tried the Auralex on my wooden dining table).

Ok, pulled out the Micro Seiki turntable, put it on the pool table, iphone on the turntable platter. Rapped the pool table at the same spot....whoa! BIG seismic vibrations registering! It’s like the turntable platter amplifies vibration and ringing. Graphically on the app, it looked quite bad. Then put the turntable on the Auralex, rapped the pool table. STILL big vibration registered through the turntable platter, almost the same as without the Auralex. This was surprising to me as my intuition presumed such a big thick platform full of foam would have done better than that.

Next, tried putting the turntable held up by the Townsend Isolation Pods.
Rapped the pool table and...this time MUCH better! The height of the spike was much smaller and most of the awful ringing was gone.

I tried some other combinations - pulled out a squat, thick wood speaker stand I’d built a while back. Placed that on the pool table, then an MDF shelf from the lovan, and I measured raps on the pool table in that configuration, and putting in the Auralex, and switching the Auralex for the Pods. Placing the iphone on top of the speaker stand, under the turntable showed fairly significant vibrations on all axises traveling up through the stand from rapping the pool table.

As before, it got even worse placing the iphone on the Micro Seiki turntable, and was barely mitigated by the Auralex. And as before, putting the Townsend pods under between the speaker stand top and the MDF shelf holding the turntable - far less vibration transmission and ringing! In fact, though there was still some vertical vibration transmitted a bit, all the other axis L/R axis vibrating virtually disappears completely.

When I put my hand on top of the MDF shelf that the turntable was sitting on, and rapped the pool table, I could really feel the vibrations in my hand resting on the stand.  But moving my hand on to the turntable base, which was held up by the Townsend pods, and then I could barely feel any vibration transmission at all.  It was quite a difference and pretty impressive.

One thing though: actually rapping the turntable itself lightly yielded slightly different results. On only the turntable sitting on the stand, rapping the table near the tone arm yielded minor vibration spikes - interesting far less vibration registered than rapping the surface the turntable sits on. Putting it on the Auralex yielded similar results, but if anything maybe a slight reduction in vibration. But when on the Pods, rapping the turntable actually yielded, if anything, slightly more vibration or ringing than the turntable by itself. Though of the several times I tried this, it didn’t seem like a big difference. To the extent that was accurate, I wonder if that means the Townsend Pods are better at isolating from exterior vibration, vs interior coming from the table.

Anyway, those are my results thus far.

Seeing the results, I’m less inclined to buy the Auralex turntable platform than I was before. (Though, in fairness, if isolation should be matched closely with equipment weight, the Micro Seiki turntable may have been too light for the Auralex to do it’s thing. Then again, it’s also significantly lighter than the Townsend pods are rated for - I got the pods rated to hold up about 80 lbs - the Transrotor and it’s coming thick wood-block base. The micro seiki is far lighter than the pods are rated for, so I don’t think they were at their best either).

Thanks for posting that; extremely detailed and informative, and interesting! I'm going to parse through it again. I think this can help others, if nothing else to get us thinking about things. The isolation/coupling interfaces for high-end turntables are so crucial!

mulveling,

Glad you found it useful.

Though after a conversation with another audiophile pal - who has long been into turntables - I’m unsure how useful the info is. He suggests that when I’m doing the tapping test around the turntable with the iPhone app, I would be creating resonances well below those that are actually important sonically. That is: they may tell me about how well the turntable can be isolated from lower frequency foot traffic or whatever getting into the table, but aside from being bad enough to skip a record, that’s generally not the vibration interference frequency range I need to be concerned with (especially if no one generally walks around the turntable when I’m listening).

Rather, we have to be more concerned with resonances more likely to infect the signal, e.g. those coming from the turntable operation itself, which manufacturers seek to diminish with various approaches (e.g. mass loading in the case of the Transrotor table).

So I’m not sure how I can use the iphone app to actually measure those types of vibrations.

BTW, I received a package I’d ordered of sorbathane pads (1/2" thick). Doing the same tests, the sorbothane didn’t seem to really decrease the vibrations showing up through the turntable, on the iphone app. But, again, not sure how to interpret that. Sorbothane surely does absorb vibrations as it is successfully used to do so in various industries. So maybe my iphone app just isn’t measuring the right frequencies where I’d see the difference.

I’m also caught somewhat between two worlds, when asking for advice on this. On one hand I’m a long time audiophile, very familiar with the audiophile world of Stereophile/Absolute sound etc. On the other, I’m a skeptic about lots of what goes on as "knowledge" in the audiophile world, because audiophiles generally don’t have a very reliable method of testing claims, so it’s something of a wild-west mix up of technical conjecture and subjective bias effects, mixed into whatever may really be happening. Researching isolation control in the audiophile community, with all the differing opinions that include IMO dubious claims doesn’t give me a lot of confidence I’ve bumped into someone who has really figured this out, in a reliable fashion.

Still, I do like to take in various viewpoints and advice to see which ones make sense to me.

@prof I think you have been badly advised regarding the deleterious effects of sub sonic interference on turntables. Seismic noise is everywhere (traffic, construction, micro quakes) and eliminating it is highly beneficial. Hence manufacturers such as Doehmann build minus k platforms into the Helix turntable and users such as me use active platforms like the Herzan. You might also like that these types of solutions are well scientifically documented and proven to work - although at a costs 

While, as I’ve previously commented, I think your solution will amplify rather than reduce sub sonic interference it would be completely wrong to assume that seismic noise is not causing problems for any turntable

folkfreak,

Appreciate the input.
 
What aspect specifically of the design do you think would amplify sub sonic interference?

@prof my error, I’d mixed you up with the other thread where the OP was planning to drill a hole in their floor and anchor everything to a single post

Anyway I’m surprised no one has suggested lead shot as a stand filling option. I knew some think the sound is not ideal and it’s obviously risky to work with but it’s readily available and has admirable deadening and weighting properties. It certainly works for me in my Grand Prix stands

I am also a big fan of cup and ball footers under stands such as the GPA Apex footers. https://www.grandprixaudio.com/products/apex They are expensive but can be retrofitted into any standard 3/8-16 .875 threaded fitting (and can also be had in any other size as needed). When I upgraded my amp stands to these it was like the amps suddenly got another 6dB of headroom.

In regard to shelf options I’d get in touch with Ron Heydrich at Marigo. He sells excellent (expensive, think $1000 each) shelves in his proprietary multi layer blend but also has many other options to damp acrylic shelves or even small pieces of his shelf material to go under existing feet and address any issues you may have with your current setup

My friend has the exact same Lovan rack. It use to ring like a bell when excited.  His Dealer suggesting filling the legs with expanding spray insulating form.  He had to fashion a longer tube from the can but it worked great!  No more ringing.

People often comment that some rack or marble plate or granite slab rings when struck with a small hammer or other implement and therefore the thing would ring under normal circumstances. Allow me to disabuse you of that idea. Don't strike the rack or granite slab during play and it won't ring. Case solved! There is much more of any issue with low frequency seismic vibration getting up through the rack than any ringing.

geoffkait,

And others will say low frequency seismic vibration isn't the vibration we need to normally worry about; we need to worry about how susceptible to vibration/ringing/feedback is the surface you place your turntable on (that is, so it won't amplify vibrations already in the turntable system).

Hard to know which to believe given all the differing opinions, and very little objective test evidence.

Thanks testpilot.  I've heard of that for the Lovan racks.  I'm still debating whether to bother doing anything like that for the rack.

@prof The vibrations that the turntable is most susceptible to ARE the low frequency seismic ones since the natural frequencies of the platter, cartridge, and tone arm are very low, around 10-14Hz. That is by design. The turntable is thus more affected by very low frequency seismic vibration (that includes frequencies 10-14Hz) than by other forms of vibration such as acoustic vibration - since it’s relatively immune to those higher frequencies, by design. Since most speakers cannot produce any significant energy in the 10-14Hz range the turntable is relatively immune to acoustic waves in the room.

geoff kait
machina dynamica

Whoah.  I just introduced myself to geoff's web site.

If anything confirms what I mentioned as the perils of asking for advice in the audiophile world, this was it. 

Nice reaction, Professor! 😃 Welcome to the big leagues! ⚾️

geoff,

On further consideration of your website, and a bit of research....I think I "get it"  (Poe's Law is always a hurdle).  ;-)

Also, I can see your point about the audiophile over-worry about ringing materials. Thanks for your response.

bdp24,

Thanks!

I have the Townshend pods.  Thusfar, in my tests using an iphone app to measure for vibration transfer, the pods have the most dramatic impact on stopping external vibrations getting to the turntable/bass.   I'm planning at this point to put the pods holding up the maple butcher-block base I'm having made for the turntable.

@bdp24 I’m pretty sure you meant roller bearings work in all directional except the *vertical* direction. That’s why they work well with springs, a la Barry Diament and yours truly, since springs are relatively poor in the lateral plane. Thus they don’t interfere with each other.

Oops, right you are Geoff. I gotta remember to proof my posts! The great thing about saying "in all planes but vertical" is that you then don’t need to list them all. Those planes (perhaps "directions" is more accurate?) include, as you have pointed out in the past, not just lateral (horizontal if one prefers), but all related. You used a term for those related planes, which I of course can’t recall. I could never be a lead singer---too many lyrics to remember. I have to make notes on my set list for live gigs, reminding me of what the beginning of each song is like. Lucinda Williams herself actually uses a 3-ring binder containing the chords and lyrics to her songs, placed on a music stand to her side on stage. As she finishes each song, she turns the page to the next song!