Feet to mount on a butcher block platform

I responded to what type of material to use under a component for isolation and to absorb vibration.

A sheet of sorbothane can be found on the cheap and you can cut it to the sizes desired.

Sorbethane will absorb vibration and also will absorb some of the frequency spectrum.

Bass where?
Bass, as in the low-end frequencies produced thru the system.

 

IOW, Sorbethane should not come in contact with a component. It affects sonics.

 

The difference in RMS between the table and the turntable is X = 2.5%; Y = 11.4% and Z = 12%. The vibration being isolated is from your speakers noting that your subwoofer is in the corner near your table and your table may be at the first reflection point for your KEF speaker. When you are taking these measurements are you using any low-pass filter and if so - what is the cut-off frequency? Wood by itself is a poor damping material - but thick sections add mass which helps to damp vibrations along with the sorbothane; although its actual performance is dependent on the forcing frequency to determine the natural frequency and the transmissibility - Sorbothane-EDG.pdf. Its actually a pretty complicated product to use correctly.

You may find this of interest - Documentation of damping capacity of metallic, ceramic and metal-matrix composite materials (utexas.edu) "Damping capacity is a measure of a material's ability to dissipate elastic strain energy during mechanical vibration or wave propagation. When ranked according to damping capacity, materials may be roughly categorized as either high- or low-damping. Low damping materials may be utilized in musical instruments where sustained mechanical vibration and acoustic wave propagation is desired. Conversely, high-damping materials are valuable in suppressing vibration for the control of noise and for the stability of sensitive systems and instruments."

 

So according to that sounds like cast iron would be the way to go sounds about right to me. Fern & Roby make what I am sure is a very expensive turntable with a cast iron plinth.

Fern & Roby

 

no low pass

If we look at the table vs. TT reduction
RMS x -10%
With the sub 1 ft. away and the speakers about 4.

But the order of magnitude is so small vs tracking force as to be moot.

From no music to music, 0.00052 to 0.00071 RMS, +0.00019
Peak 0.0015 to 0.0020, 0.0005 g
A 33% increase looks bad, but in context, 0.0005 it looks different.

The frequency spectrum is all below 50 Hz.
So I assume most is from the sub.
No real isolated frequencies, pretty much evenly distributed.

FFT in the 40 Hz range, pretty much the same down to 0, hash

 

OMA also uses cast iron - Oswalds Mill Audio - Turntable | OMA, while the SAT-SD1 Analog Corner #304: SAT XD1 record player | Stereophile.com uses an alloy of Mg which is also known for high damping - but it also sits on a Minus K isolation platform Vibration Isolation Tables, Platforms & Systems | Minus K Technology.

Not to derail this post, there is always the alternative of constrained layer w/viscoelastic damping which when done correctly can achieve very impressive damping. I modified a VPI TNT plinth by adding a 1/4" cast aluminum constrained layer w/viscoelastic damping and the results were quite impressive. Before the mod if I tapped on the plinth with record playing I got a response through the speakers, after the mod - nothing.

 

The most surprising thing to me is the measurement on the TT, running with music vs. running no music.
There is essentially no difference.

Delta Music - no music:
Peak 0.0003/0.0002/0.0002
RMS 0.0001/0.0000/0.0001

for example x peak no music to music
0.0017, the TT delta is only 10% of the increase, so only 10% of that is due to music, the balance due to the TT itself.

This implies that no external disturbance due to the music is getting thru to the TT.

And the increase between the TT when playing is due to the TT itself.
And this is absorbed partially by the pods and transferred to the block.

From this it appears the TT is very well isolated.

 

Is the floor the turntable mounted solid to the foundation or is it suspended above a basement? If its suspended walk around while taking the measurements. If the floor is very stiff you will see little change, but any change will be at very low frequency ~2-3 Hz. The other item is that you already previously said that the frequency causing the acceleration was mostly 50 Hz and Sorbothane can be very effective at the frequency, but is very poor at very low frequencies such as that caused by foot-fall.

For the Sorbothane pod you are using - what is the natural frequency and what is the % isolation. I just used 2" x 2" disk with a 50 duro, 20% deflection, 25-lbs/pod and an excitation frequency of 50-Hz and its shows 91.71% isolation Sorbothane Engineering Design Guide Application - Vibration. However if I take the same pod and change the excitation frequency watch what happens; pretty evident that its not very good for foot-fall;

250-Hz = 99.55%
100-Hz = 97.67%
50-Hz = 91.71%
25-Hz = 69.45%
10-Hz = -90.27% (this is near the natural frequency and it now amplifies (almost double) the motion).
5-Hz = -34.99%
2-Hz = -6.16%

 

Only TTs and CDPs need that. There's no microphonic effect from vibrations on solid state gear without moving parts. It's snake oil.

 

6" reinforced concrete slab on grade.
But foot steps are measured but do not impact playback.

% isolation (I measured it yesterday after @avanti1960 mentioned it)
26%, they recommend 25%
not sure which durometer rating, 1.25"
TT plus block ~ 35 lb

the clincher for me was no difference music vs no music (running) on TT plinth.

I can jump 3' away and it doesn't skip.

 

Good to know

 

3 jumps, 185 lb., 1' high, 3' away
On TT plinth
You can see the small disturbance when I push off and big one when I land.

 

My wonderful TAD D-1000 CD/Pre/DAC sits on
Black Ravioli on top of
Electric Beech platform (butchers block could do) on top of
Black Ravioli on a
Creaktiv rack

Cheaper and great VFM are RDC cones and bases.
Use 3 instead of 4 and no need for levelling if a problem

 

You guys are making me anal.
I'm going to re-do my cheap Fluance RT82 turntable which has shaky feet from the factory.

These simply screw up and down to adjust height but stay "loose" which bothered the heck out of me.
As the tone coming off the table was extremely distorted with lots of harmonic hash I simply removed the feet entirely and placed the entire mess smack on top of gooey absorbent silicone pads.
This soaked up a lot of hash but killed the bottom end bass and muffled the top end treble.
What a pain!

So thanks to you guys making me even more dissatisfied with my cheap setup and poor results I am forced to try a new setup.
I'm going to add 4o cents worth of LOCK NUTS to those feet that Fluance puts on their tables.
For some reason Fluance doesn't include the nuts!

By cinching down the threads coming out of the feet I will tighten up the nuts on each foot's shaft up against the underneath of the table.
This will lock the feet solid for a change and theoretically improve the "draining' of high energy hash out of the table and into the wood platform underneath it.

All this for a cheap crappy table that is a bit of a joke I am afraid.
Not to slag Fluance.
The table actually works much much better than its price would indicate.

Fluance actually took some time thinking about performance with these cheap rigs---even the tonearm wiring is above entry level (its like copper Litz!).
So excuse me while I have a little cheap fun here.
I'll let you know if the RT82 begins to perform like a GyroDeck, ha ha.
And I'll let you know if tightening up the tonearm onto the toneboard makes the arm sound like a Thomas Schick 12 incher.

Fat chance.
Hey I bought the Fluance for FUN just to play around with something inexpensive and see how far up the ladder it could go.
So far the table is better than it should be for the money.
But I have never been someone who could leave well enough alone I am afraid!

 

[QUOTE="pacvr, post: 28006772, member: 115871
[/QUOTE]

Excuse me while I wipe the drool off my face.
Turntable porn!

 

OK.
Took the whole table apart and discovered the main culprit was the tonearm.
When I tugged and wiggled the arm it was loose as heck and making a graunching noise if you tapped it on the top of the pivot ring.
The entire tonearm was RATTLING!

So I took a deep breath and filed down a screwdriver until it fit the tonearm adjustment fitting---and tightened the crap out of the bearings.
Not really.

I tightened them until the free play was gone and then locked them down .
Then I performed a "float' test to see if the arm was still moving with total freedom and no sticking.
Setting the anti-skate to number one I blew the arm sideways and it bump stopped at the spindle and then slowly and smoothly swept back to the arm rest.

I THINK the tone is remarkably improved.
Songs that previously sounded like a noisy HASH now sound beautiful and without any touch of grain.

I will have to wait until I drag my Technics SL1210M5G back in to compare it directly.
Previously the Technics embarrassed the Fluance with much deeper bass and way better treble.
Now I BET I have closed the gap!

Thanks for making me anal about this stuff guys...
I may have just improved my late night stoner experience.
I can't wait to go "off to the zone" and dwell among the giants of music once more in fantasy land.

Ah---fantasy land.
Where turntables provide all the warmth and aural comfort food one could ask for.
Yeah baby.
THAT'S what I'm talking about!

 

I FIXED THE FLUANCE FEET once and for all!
It made a BIG difference fitting them SOLID to the turntable instead of letting them wobble around.
Took off all the stuff to work on the Fluance


The feet were simply screwed in and left loose by the factory


I shimmed the shaft after not being able to source such a fine thread as a nut---this worked even better at making the feet SOLID mounted for a change as the feet no longer can shift up and down on the shaft like they used to do---Fluance might have thought that was a good idea for isolation but boy making the shafts move up and down was a crappy cheap way to float a table! Now the feet are completely rigid and the platform board has all the isolation necessary UNDERNEATH the entire setup as it rides on silicone pads...
This has drained resonance away but left good tone alone!


The table is now working at a much higher performance level.
In fact it actually is singing and the bass is terrific and solid and the top end is now clear---Yay Fluance!
Not bad for $300---and I am getting the FULL tone from that expensive LOMC cart at this point---wow!


See what you guys made me do?
Because of all this talk about footers I went and fixed my setup.
Between tightening up the tonearm bearings and addressing how tight the body was tuned---wow what an improvement!
Turned a cheap sloppy turntable into a hard working clean sounding LOMC mamma-jamma.
Yeah man!
THANK YOU ALL!

 

Some more useless measurements

On plinth, a bit above normal volume, bass heavy jazz
5 sec music/ mute 5 sec for 3 cycles
Did this 3 times
Exported into excel

Found highest and lowest for x, y and z both Peak and RMS. Rounded highs up and lows down to get conservative deltas.

imho pretty well isolated


using the highest RMS value that basically varies the 2 g tracking weight from 1.9999 to 2.0001.

 

Nice job, if you want to make the spacers look more integrated with the feet - you should be able to buy nylon fender washers. Amazon.com : nylon fender washer

 

I'm trying to drain midrange distortion.
I wanted metal to metal.
PLUS using washers can level the turntable now.
I have two extra on the back foot.
But thanks for your suggestion.

 

Not true. Vibrations affect capacitors and thereby generate a small signal which can be measured. This is why high end capacitors spend so much time on damping and materials, or why some manufacturers take care to isolate capacitors from vibration. Now, whether or not that signal has an impact on perceived sound performance can be debated, but it is incorrect to say that SS gear is unaffected by vibrations.

JohnK

 

Thank-you! and to paraphrase a line from Lucille Ball; "And it sounds good too!".

Some years back I went big into digital Krell DT10 to a Wadia 27IXv3. But Philips stopped making the drive with no notice and Wadia stopped any support of the product so I had the realization that both were destined to the landfill; I got burned; never again. So I committed/surrendered to vinyl, and I have no regrets. I got some awesome deals on B-stock, used and new items and with some sweat equity after 5-yrs that table with both tonearms and both cartridges (Soundsmith Boheme & Paua) and a VPI SDS, and two phono preamps; the sum total does not equal what I once spent on digital; and the vinyl playback is better and will likely last and be supported for a lifetime (or two). I have digital, but its simple (Burson Conductor) and inexpensive; and its staying that way.

 

Vibrations, on good equipments, have been internally taken care of by the manufacturers; no need to decouple an amp. No they don't translate into anything audible, for nothing mechanical is being rattled. But if someone likes the looks of their things on butcher blocks, hey, who am I to criticize, right ?

 

ALL manufactures need to make money, whether they make cheap washing machines or expensive amps. Draw your own conclusions from this . Holier than thou manufacturers don't exist! Which is why there is always room to improve something.

 

It's amazing how little work can yield free improvements.

maybe something like this in place of the washers. Tighten until you get a little tension and no wobble?