2. misc-audio
  3. 138518-118236

Best building material for vibration free shelving

I am building some built into the wall shelves for my VPI Classic 2 SE turntable, amp, preamp, CD player, and old Burwen TNE 7000A transient noise eliminator (that’s one for you old-timers to remember), as well as my DISH Network receiver box. The shelves must match in appearance the typical looking built-in wood bookshelves already in the room. The shelves will be located directly under my 45" wide flat screen television. They will be wide enough to hold two components side by side, other than the VPI turntable which will have the top shelve to itself due to its extra width. I will be building the shelves high and deep to allow for plenty of air circulation around the components. They will be painted.

My question is, what materials might you suggest building the shelves with to minimize vibration? If they were for books I’d normally build the sides, and top out of 3/4" birch sided plywood, the back out of 1/4 inch luan plywood, and the shelves out of oak to deal with the weight of the books without bending. I will be adding vibration damping feet under each component and am not looking for suggestions along those lines, only material and perhaps design recommendations to reduce vibration.

I was researching this last night online and on site, and saw recommendations to use four thicknesses of 3/4 inch High Density (HD) MDF, also to use granite or marble under the turntable, among other recommendations. I was wondering how birch veneered plywood would work too, as it’s ply’s, I believe, have their grains running in opposite directions. Maybe there’s some way to isolate the uprights from the horizontal shelves to reduce vibration transmission.

What would you think would work best for these built-ins. I’d appreciate any recommendations you have or your experience on this subject. Thank you for any ideas.

Mike


skyscraper

Showing 12 responses by lowrider57

lowrider57's avatar
lowrider57
5,418 posts
 
@n80, not a good idea to use the preamp’s rubber feet coupling into a hardwood footer. You can’t rely on the stock rubber feet to provide any isolation; also, rubber will colour the sound and the feet are not secure since they are either glued or screwed into the preamp chassis.
For transparent isolation, footers should sit under the component itself. This way any vibration will travel from the underside of the chassis to the footer. There are two methods of isolating a component, either drain vibration to a platform or plinth, or decouple the component from the shelf.

There are many threads on this subject in the archives. Geoffkait has provided very good advice regarding acoustic isolation.

Your walnut footers look like a good design for draining vibration and also for isolating acoustic/ mechanical vibration from the shelf. What you are missing is a set of cones where the flat end sits under the preamp and the point sits in the dimple of the walnut footer.


lowrider57's avatar
lowrider57
5,418 posts
 
@williewonka, have you compared your wood cones with Myrtle wood blocks? I'm using the blocks under my tube amp and find that the image is not well focused perhaps due to vibration.

I like the idea of using wooden cones rather than blocks. I also found these cones...
http://www.russandrews.com/us/system-racks-supports-equipment-feet/
These are made of oak, the Glasshouse are beech. Any thoughts if using cones would be superior to the Cardas Myrtle wood?


lowrider57's avatar
lowrider57
5,418 posts
 
@n80, I'm sure the feet on your ARC aren't crappy. In fact, some high-end manufacturers use quality aftermarket footers on their amps so that the voicing is what the designer intended. My point is that usually the feet on a pre or an amp are screwed or bolted into the chassis. This creates a weak spot that is vulnerable to vibration.

It's great that you're pleased with the sound of your system. i remember when you came to the forum asking for advise. And BTW, your walnut isolation blocks look better than most tweaks I see for sale.


lowrider57's avatar
lowrider57
5,418 posts
 
@n80, I’ll address one point, your component placement should be fine. It’s furniture or audio racks between speakers that affect mostly imaging and other sonic attributes. Open racks are preferred. Speakers need space or air around them for best reproduction.
Most owners move their speakers forward of the rack/console.

lowrider57's avatar
lowrider57
5,418 posts
 
@williewonka, thanks, the cones are a similar style. I guess there's no way to predict the audible difference between beech and oak as footers.

 With regard to a wood platform or plinth, is it possible to make an educated guess as to the sonic effect between different hardwoods? The difference between a hardwood and softwood is obvious IME.
 @n80 perhaps you might have an answer?


lowrider57's avatar
lowrider57
5,418 posts
 
@gawdbless , I'm using that exact bamboo board turned upside down. It was recommended on a thread a while back.
I have seen better quality bamboo cutting boards, but this one is strong. It's under my 60 lb. tube amp. I'm in search of the right kind of footers, haven't found them yet.

lowrider57's avatar
lowrider57
5,418 posts
 
@williewonka, thanks for the info. I've been reading that the density of the wood is the main criteria for isolation and preventing transfer of vibration. As you stated, porous wood will result in resonances and less isolation.

I built a shelf for a heavy SS amp using finished ash from Lowes. I doubled it and used wood glue to create a 3 inch platform. I then used Herbies soft dots underneath.
   The wood looked beautiful, but was not very dense like maple. However, it had a nice tonal quality.
 
lowrider57's avatar
lowrider57
5,418 posts
 
@williewonka , I don't believe Sorbethane or rubber should ever touch the component or footer. It may be used as a layer between a platform or plinth and the shelf.

I'm familiar with that link and I'm a believer. Geoffkait has also provided many comments on the benefit of draining vibration, (Yes our Geoff really does know physics).
I took his advice a while back and ordered DH cones. I'm using them under my PWT transport and the sound is more open and detailed with no harshness. BDR Racing cones sounded harsh. 

So, I'm now sold on isolating all my components in this manner.
 

lowrider57's avatar
lowrider57
5,418 posts
 
Yes Steve, keep me posted.

What kind of steel ball bearing feet did you use? You’ve got me worried since I ordered some footers today on a close-out...
https://edensoundaudio.com/shop/terrastone-roller-bearing/

Maybe I should have stayed with cones.

lowrider57's avatar
lowrider57
5,418 posts
 
@williewonka; cool website, I bookmarked it.
The Terrastone is a proprietary composite as are many of these offerings from specialty companies. They get good online user reviews and VPI recommends them as feet for their TT's.
   I don't know about the construction of the TerraStone Roller Bearing, but it is a brass ball. In a review it's compared to Symposium rollerblocks.
I will definitely report my results.

Regarding your footer design, Sorbothane is a substance which dampens vibration, but in your case, restricts the vibration from being drained. It also imparts its own colourations.
And I just re-read your post..
Then a fellow DIYer pointed out that the feet were not allowing internal vibrations from the transformer or airborn vibrations that might vibrate the cabinet, from being "drained" from the amp - he suggested I try brass cones or wood cones without any "cushion" material between them and the amp.
So, you already know this.

I know you're a DIY'er, but I've used some Herbies to protect the surface of the plinth w/o any audible side effects...
https://herbiesaudiolab.com/collections/system-isolation/products/thin-grungebuster-dots



lowrider57's avatar
lowrider57
5,418 posts
 
@williewonka, the brass cones look beautiful. A set of brass "audiophile approved" cones would fetch hundreds of dollars. Great that they’re performing so well, and well done on admitting you've made mistakes along the way.
Lots of good reading on your website as well.

I went all in on maple platforms for my components after reading so many recommendations. It’s like I upgraded my components; the imaging is very focused with XL separation of instruments, micro-dynamics such as the attack and decay of drums are now more revealed, and the top-end of my digital sounds smooth and organic. Music is much more realistic.
I’m using the suggested setup of hard footers under the components which drain vibration into the maple plinth. Then pliable damping material between the maple board and the wood shelf.


lowrider57's avatar
lowrider57
5,418 posts
 
Slaw, I dont have room to try springs in my rack which has fixed shelves. On each component I have damping weights on top, next are the footers, a 1 inch maple plinth, then a decoupling layer. I also need space for the heat from tubes.
For footers I’m using some DH Cones and also footers utilizing brass bearings.
https://edensoundaudio.com/shop/category/terrastone-footers/terrastone-roller-bearing/

Between the maple and shelf I’m using Herbies Grungebusters which are compliant and recommended for platform decoupling. I’m not damping the entire platform, only the four corners to get a lively sound from each component.


More to discover