Buy a sheet of 3/4" Baltic Birch plywood (about fifty bucks), and cut (or have cut at a cabinet building shop) two pieces to size. Put Green Glue, EAR Isodamp, ASC Wall Damp, or other constrained layer damping between the two pieces, and screw the pieces together. Put a set of springs, roller bearings, or other effective form of isolation under the platform (Townshend Seismic Pods are great, but not cheap). Enjoy.
Home grown turntable platform/base?
I picked up a used Pro-Ject Debut Carbon turntable for the family room. We are not big into vinyl, mostly listen to digital, but my 16yo daughter has shown an interest in getting some records. I’m getting excited about her interest in vinyl and audio. What is a good platform material to use? Wood? Granite? Should I add sorbothane and/or spikes underneath? I’m not looking to spend a lot but feel I should have some decent isolation for it. The turntable currently sits on a hollow shelf. It’s where it has to be so I need to make this work.
Thanks for any input.
Thanks for any input.
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@bdp24 +1 I might also suggest substituting THICK maple butcher block, 2 1/2" or greater, for the baltic birch. It would require two of the butcher blocks to accomplish your goal, but it would work. Thin sorbothane sheets between the layers might also be effective, but with the weights involved, 30 Duro will probably not work as well as 40D or 50D. More than 50D would probably not accomplish your goals as effectively. |
If your making a platform with layers, use a proper glue for the specific materials. Don't use screws, they defeat the purpose and allow the vibrations to freely travel through the platform circumventing the layer effect to reduce transmission of vibrations . The Herbies materials are better than sorbathane which around turntables will muddy the bass lines and mess with the treble frequencies where as the herbies materials are designed to avoid that specific issue. If foot falls are not a problem , a simple gluing of a couple pieces of 16 X 18 approx. void free ply with 4 herbies tall tenderfeet will do as well as what you would realistically need/want with the project table. The plywood is just an economical choice that works quite well, other materials may be substituted that cost more, but don't always deliver the results wanted by adding vibration tone of their own. I made one like this for my daughters Rega RP6 and bought a cheap piece of leather from a fabric store and glued it to the top to dress it up and very fine sanded the sides smooth and sealed them and put 4 Herbies Tenderfoots on and done. Works great and looks quite sharp actually. A sand box is a cheap easy build as well if more extreme measures are wanted/needed. If foot falls are a problem, then isolating the table from the floor with a wall mount is the best and final method for that issue over suspended floor deflections. Good luck, nice to see the gift of music appreciation being joined together...……... |
Thanks for the excellent replies everyone, First of all, sorry but what are foot falls? I like the idea of the Herbie’s Tenderfoots. Is there any way I can do this a little more low profile such as just using one piece of birch? I like that idea with the leather covering. I’m trying to keep the wife acceptance factor here. Is a piece of granite or marble a bad choice with the Tenderfoots? Thanks again. |
Footfalls are when footsteps cause the suspended floor to transmit vibration to the turntable. It can be pretty bad causing skips or thumping. I’d recommend a 3/4 to 1 inch thick block of granite (not marble and not tiles) on spikes or cones or springs or ball bearings as above. It will tighten the bass and make the music sound cleaner and faster. You can try a sheet of 22ply under or instead too and compare. |
Thanks noromance, I don’t see me having a footfall problem as the main floor we walk on is concrete. This is a raised shelf/ledge that was built into the wall when the house was built. So go spikes over the Herbie’s Tenderfoots? I could get a hold of a piece of granite like that but would it be too heavy for the Tenderfoots with the turntable anyway? |
@asahitoro Good. I have concrete too. The thing to remember is that, as a basic rule, the harder and less compliant the support, the faster, more dynamic and more detailed the sound becomes. However, you can swing it too far and make the sound a little, um, sterile. Marble and glass can do that. Soft woods go the other direction with the sound becoming softer. It seems ridiculous but it is true. Some argue that low frequency resonances need to be attenuated using damping but, to be honest, I have not found it to be a big deal. Hollow shelves or cabinets are a no-no. Try a 16"18" piece of granite from a fabricator. Stand the granite on 3 points - brass, or something. Ensure all is level. Let us know what you end up doing. |
Thanks Steve, I'm digging this Mapleshade unfinished block: https://shop.mapleshadestore.com/18-x-15-x-2-Ready-To-Be-Finished-Maple-Platform/productinfo/18X15X2... Would this be a good combo with the Herbie's Tenderfoots or would the granite/spikes route work out better? |
This is exactly how my daughter gained an interest in vinyl. Same age too. Started with the project and that led into a VPI prime signature. We use the butcherblockacoustics platform. Nor very expensive a beautifully made. It's amazing how 3 years later my daughter has collected over 100 records of her own. Met Michael Fremer and has been to numerous audio shows and shops. Enjoy |
Regarding has2be's statement that screwing the two pieces of birch ply together will defeat the isolation provided by the constrained layer damping placed between them, that layer of damping material is put there not to provide isolation for the turntable, but to absorb and dissipate the resonances of the plywood itself. Green Glue, ASC Wall Damp, and EAR Isodamp is too thin to provide any isolation. It is the springs, roller bearings, Herbies feet, or Seismic Pods (or even slightly inflated inner tube) placed under the shelf that provides isolation, not the constrained layer damping. No harm in trying the two pieces of ply both screwed together and not, though. However, Green Glue doesn't completely harden, which would allow the two pieces of ply to slide around in relation to each other a little. ASC Wall Damp is tacky enough to keep the pieces of ply from sliding against each other, but EAR Isodamp isn't; if using it, the two pieces of ply will have to be attached to each other in some fashion, ergo my suggestion of screws. Since the ply/constrained layer/ply construction should function as a single unit, you actually WANT the two pieces of ply to act as one. The reason for using two is to increase the stiffness of the shelf, and to allow the installation of the constrained layer damping, to make the shelf less resonant. If you want a layer of isolation-proving material between two outer layers of stiff material, the Symposium shelves are the way to go. They have outer layers of stainless steel, with a thick layer of foam between them, to provide isolation. Symposium makes a version of their shelf with springs attached to the bottom, specifically for turntables. That model is relatively modestly-priced, around $350-$400 I believe. |
Quote Yes that is what the layer is there for, no question. However, the screws still allow the resonance to travel straight "through" the absorbing layer from one ply to the other ply....., it stands to reason . I know the concept well, and its intended purpose and the screws will and do defeat the performance of impeding those resonances. There are adhesives out there that defeat the problem you create by not using an adhesive that will act as you require it to as well.... |
Good point had2be, one that had not occurred to me. I have Solid Steel racks, which unfortunately have 3/4" MDF shelves (yuck!). I bought extra top shelves to double the thickness (for my fairly heavy turntables), as well as ASC Wall Damp cut to the size of the shelves, but haven't added them yet. I'll eventually replace them with BB ply. But no screws! ;-) |
Thanks again for the excellent replies everyone, I’ve been looking at maple blocks on Amazon including the Butcher Block Acoustics one mentioned. Prices seem reasonable and I already have some spikes. What is too thin for the block to be effective enough? I’m looking at 1.75" ones and the 3" BBA one. Is Maple the main choice as I see Walnut for more? |
asahitoro, even if you go with maple or butcher block, consider getting two pieces and placing a thin sheet of constrained layer damping of your choice between them. That will mitigate the resonance found in all materials, including wood. Actually, especially wood---that's why they make drums and guitars out of it! Another thing to do is put the grain of the wood in the two pieces 90 degrees opposed to each other; one with the grain front-to-back, the other side-to-side. That will increase the stiffness of the assembled shelf. |
Thanks again, I'm not trying to be cheap but I only have $275 into the turntable so I don't want to over do it. I'm sure there's point of diminishing gains for the the Pro-Ject and what it's capable of. I'm thinking $100 max on this platform. I can get a 3" BBA maple block for under that. I already have spikes and it comes with 4 'Anti Vibration Pads' to try as well. I can get a 1.75" thick piece of walnut from them for the same as a 3" piece of maple. Stick with 3" of maple? |
A sheet of 3/4"/19mm 13-ply Baltic Birch plywood (it is available in both 4’ x 6’ and 5’ x 5’ sheets) will cost you only $50 or so. Cut two pieces to size and glue them together. MUCH stiffer that the twice-as-thick 3" thick piece of maple, and more non-resonant. While some people like the sonic signature of Maple, remember, it is stiffness and a lack of a sonic signature we want in a support platform, not a pleasing coloration. IMO, of course. |
I’m setting up a turntable in another room and am going to get another block. How important is the thickness and wood type given my choices at the same basic price point? I can get a 1.5"-1.75" thick piece of end cut walnut for the same as a 3" end cut piece of maple. I’ll be putting Herbie’s grungebuster Dots underneath. Thanks. |