Would a sandbox be worth the effort?

I can easily make one up, four 2inch high sides and an inch bigger all the way around than my Signal Guard 2 isolation platform. I would cover it with some kind of rubbery fabric and remove the cone feet on the signal guard sitting it directly on the sandbox shifting the sand to level the TT.

I’m not sure if I would be wasting my time mainly because the music is played in the other room or through headphones.


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Here’s another idea. What if I removed the Signal guard and built a sandbox with as I described above but with plywood base that separates the motor from the plinth.

I also thought about the vpi - mini hrx feet but I think my powercord would be a problem so it may be a waste of money.

Anyone else using a sandbox?

 

I just put the final coat of paint on mine today! I should have it mounted up by tomorrow night. I can't give you any input yet, but I will be sure to report back. My rack is very simple and utilitarian, but not the greatest isolator. I intend to use the "tap test" to see how well my sandbox works.

My basic design uses 2.5" MDF boards for the sides and a 3/4" MDF board for the bottom. The top is 1/4" glass that will have 3/16" gap all around in order to float in the sand. For now I will be using cork feet that are about the size of a penny and shy of a centimeter in height. I will put little rubber pads on those.

 

I find the idea of that much grit near a vinyl system very disturbing.

 

Surf's Up should sound great!!

Let us know how it does and sounds.

 

I whipped this together today out of stuff I had lying around. I bought the sand 2 weeks ago and knifed the bag open to let the sand dry out. I’m waiting for my wife to get back she picked up a ½ a yard of black marine vinyl. My plan is to contact cement it to the white melamine boards as you see them in the photo. It would be cut to the outside dimensions of the box and just lay there. I’m not going to cut the vinyl around the motor base at first. If I don’t need to it would make a good barrier from the sand.

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For less than $100 to add density and isolation, I think I can manage to keep the sand under the glass. My vinyl is free of fingerprints too.

 

Here it is. I'll say this I have some subsonic noise that I have been looking for ideas to solve, it didn't help that at all. I'll have to see if it sounds any better. I think it will be the same.

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I recall a crazy Japanese turntable fan who cut a hole in his floor, went through to the dirt, then anchored his turntable stand in that and put a thick rubber around it to insulate it from the floor. So effectively, the turntable stand was isolated from his entire house. That's dedication.

I used a couple of concrete blocks for a few years, but eventually just got a big metal stand with tiptoes, and that worked fine for decades.

 

A dealer once told me about a customer that had a concrete column pored from the basement through the 1st floor at turntable height. I can see that. Good thing I don’t have and wet concrete lying around,

 

Is it a hum? Ever try running a wire from the spindle base under plinth to the center screw on nearest outlet?

 

No No it's below 20Hz you can't hear it. May people have it that's why many phonostages have subsonic filters. It has been suggested to find a way to dampen the tone arm and so far there is no way.

 

I have everything--the rack and speaker stands-- on concrete blocks I treated so they wouldn't shed dust. I kind of had to do. Our living room is actually one of our 'wa-****su' rooms, a tatami room. Not the best place for a turntable, but there ya go.

OK, this is ridiculous. The family function editor blanked out 'washitsu'. It's not an expletive.

 

I think it sounds good and worth the effort. There may be subtle improvements or it sounds the same. The TT is incredibly stable when I tap the side of the box it has mass. I think the vinyl was a good choice too. The plinth and motor used to slide around, not now. Isolating the motor has to do something !

 

I don't know what specifically the source of your noise is, but the proximity of that speaker to the turntable, is probably going to be problem regardless of what you do to control vibration coming up through the stand (not to mention that speaker wedged tightly into the corner can't be sounding it's best) -- sometimes the best thing to do for turntable isolation is to reposition the gear. If that speaker is playing loud, you might have airborne vibration coming from above, not below, and so isolation below the deck isn't going to address it.

Second, if you really are having LF coming up through the floor, some kind of air bladder isolation seems to work really well down to something like 2 Hz. Of course you can buy something like the stuff Townshend makes with is based on the kind of stuff used with electron microscopes, but it's pricey. Personally I float an MDF shelf on some only slightly inflated small tire inner tubes atop a mass loaded rack as a kind of home brew air bladder iso, which works fine if you don't have the money to spent for better and more elegant solutions.

Third, usually, truly subsonic noise is usually resonance from the table itself -- most commonly not well controlled arm/cart resonance (I mean what really is moving in your room below 20 Hz?) -- and any attempt to isolate the table from the stand isn't going to address that at all. All traditional arms and carts have a subsonic resonance. You need to make sure yours occurs at a frequency not excited by record vibrations -- that's a matter of picking a cart with the proper compliance for the mass of your arm -- and that the cart suspension is good, and then the movement of the arm can be fluid damped to control what resonance is left.

 

Those are just monitors the sound goes though the wall into another room.

 

OK I'm on your side now. One of my miters opened up a little. I think I may have under estimated the forces of the sand. The other thing the sand still had a lot of moister. At least I’m only out the cost of a can of paint and a ½ a yard of vinyl.

 

Man, that sucks! I used Liquid Nails along with actual nails along all joints and I caulked all the interior seams. I've had my 65 lb Classic on top for days now with no problems.

 

BTW, if anyone is interested in playing with the DIY isolation and/or sandbox idea, I used these two sources for inspiration:

How to make DIY Highend Isolation platform base

http://wardsweb.org/audio/isolation_table.html

 

I was going to post a link but I see rob303 already did. Originally I built the sandbox for my Rega Planar 3 that had a bad rumble being picked up from the motor. The sandbox silenced the table beautifully. After the Rega I used it with a Kenwood KD-550. I'm now using it with my custom Roksan Radius 5.

 

That is funny. I have always had that idea, like a separate foundation for the table separate from the building's foundation. I am certain that in a surprisingly short time the foundation would shift enough that it would tilt and contact the actual foundation. But still, totally compulsive and crazy but sound at the same time.

 

Thanks for posting the links
I really don’t think it improved the sound but was worth the test. I could make another one and spend a little more time making it stronger. Perhaps if I had it set up in the listening room it would be worth another test.

 

Hey guys I took another stab at it. I took a little more time. This one will not come apart and will last for 300 years give or take. Solid oak base off a job also. It was pre-finished not my favorite color but the finish is sturdy and will last. You can see the aluminum angle I use to hold the corners together.

Also my last attempt I rushed it to hear the sample that day not only was my design not strong enough the sand was definitely wet I’m sure that makes it less effective, it was bone dry this time.

I used the same white melamine board and vinyl I rolled the edge down along the edges of the box so there is no direct contact from the melamine and the oak ½ to ¾ space but the vinyl may result in some loss of effectiveness but I really like how it contains the sand.

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Hey Rob how does yours sound. I can’t believe how much the subtle improvements impacted the overall sound. Better bass the details are clearer the vocals are clearer and more distinguishable. Admittedly there are other factors; the C2500 becoming well burned in as well as the Shunyata Venom usb cables also being burned in.