These all sound like good ideas;  however, I find I'm plagued with air borne acoustic feed back.  My speakers are on a concrete floor and my sound equipment, including the turntable, is in a shelving unit built into the wall surrounded by isolating rubber and behind a large glass door with rubber surround.  The feedback frequency is sub-sonic, (more felt than heard).

db



>________________________________
> From: Tom Fine <[log in to unmask]>
>To: [log in to unmask] 
>Sent: Tuesday, June 12, 2012 7:06:05 AM
>Subject: Re: [ARSCLIST] Turntable Stand recommendations
> 
>Unless you have an ancient or dirt-cheap turntable and unless your turntable sites on a wobbly floor or next to a shakey old furnace, you don't need to do anything radical. ALL decent-grade modern turntables are built with many rumble-killing features. Before you go to any extremes, try a record clamp and a heavy rubber mat (definitely instead of a cheapo felt "slip-mat") on your platter. That should solve the problem. If there really are vibarations coming up through your table or stand, then move it to a less wobbly floor or away from the walls by just a few inches. Failing that, a rubber isolation mat under your table should help. Having some mass to your shelf or table is a good thing, but it's as simple as putting a few cinder blocks on the bottom shelf, no need to spend a lot of money. But, as I said, good quality modern turntables are designed with vibration-killing features like floating arm-attachment plates, isolated motors, isolation feet of
 various varieties and you can buy excellent and effective heavy rubber platter mats and clamps that are as simple and cheap or as exotic and expensive as you wish.
>
>Jerry provided a good source in McMaster -- sensibly-priced, science-based industrial solutions. It keeps you free of the hype and hooey that surrounds many "audiophile accessories," one of the more cynical and wallet-draining parts of the audiophillic world.
>
>I do agree with Carl Pultz about glass shelves, glass can resonate with speakers and get other strange and unexpected vibrations, just like windows. However, if the glass is strong enough, a granite base like someone else linked should solve that problem, even moreso if a sheet of rubber were put between the glass and granite.
>
>A friend of mine got into the "vinyl revival" and put his mid-priced turntable into the same built-in unit where his stereo and TV reside. He was getting rumble coming up from the floor, transmitted through the cabinet. We solved this using a thrown-away old multi-layer rubber and foam typewriter mat that I had saved from the dumpster at work. It makes sense -- anything that keeps an IBM Selectric from resonating down a desk into a floor will sop up resonances from a floor up into a shelf, especially when combined with turntable feet and floating top plate.
>
>-- Tom Fine
>
>----- Original Message ----- From: "Jerry Hartke" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Tuesday, June 12, 2012 6:32 AM
>Subject: Re: [ARSCLIST] Turntable Stand recommendations
>
>
>> McMaster Carr sells a wide variety of vibration isolators.
>> 
>> http://www.mcmaster.com/#vibration-isolators/=hxyojf
>> 
>> Prices and service are good.
>> 
>> Jerry Haratke
>> 
>>> -----Original Message-----
>>> From: Association for Recorded Sound Discussion List
>>> [mailto:[log in to unmask]] On Behalf Of Don Cox
>>> Sent: Tuesday, June 12, 2012 5:15 AM
>>> To: [log in to unmask]
>>> Subject: Re: [ARSCLIST] Turntable Stand recommendations
>>> 
>>> On 11/06/2012, Shai Drori wrote:
>>> 
>>> > Hi Dan
>>> > Before I bought the EMT 950 I made a stand out of concrete. Made damn
>>> > good isolation, was a bitch to move (never did). Cost in US$ about 60.
>>> > Could make it look nice as well if you add color or wood panels. Shai
>>> >
>>> Concrete alone will not absorb vibrations. Concrete plus rubber will.
>>> 
>>> I have used a paving stone on top of an inner tube, but being so heavy
>>> it was inclined to tilt.
>>> 
>>> However, there are various commercial mountings for heavy machinery that
>>> could be used.
>>> 
>>> The aim is to have a setup whose natural frequency is lower than 0.5 Hz.
>>> 
>>> Regards
>>> --
>>> Don Cox
>>> [log in to unmask]
>> 
>
>
>