I am not a believer in a lot of audiophile tweaks but I just found something that is pretty amazing. I put these under my ALON IVs Amazon.com: Isolate It: Sorbothane Vibration Isolation Circular Pad 50 Duro (.25" Thick 2.25" Dia.) - 8 Pack: Home Improvement and I thought it would make some improvement but it was more than just a little improvement. The sound stage is much bigger, the depth is greater. The mids and the highs have more focus and the overall sound is much improved. The bass is tighter and the speakers seem to completely disappear. These don't cost that much and for what it did for my speakers it was well worth it. Honestly I was simply blown away by the difference in this simple tweak.

Currently my speakers sit on 7 inch piece of granite on top of the carpeting on top of a cement floor. With this addition there are now 1/4" X 2.5" Sorbothane disks between the granite and the speakers.

The company that makes them has a website Isolate IT! Vibration Damping Products in case you may want some other sizes.

Disclaimer: I don't have anything to do with this company I just bought their product.

Let me know if you try this. Thanks

Is it an elastomer, like moongel?

When I used to setup massive sound rigs for Raves and clubs turntable feedback was a real problem. Tennis balls, floating from wires over a rack, etc tricks where used with limited effect. I called up a sorbothane producer got two sheets and stuck then under the decks. Never, ever a feedback problem again.

I also use Sorbothane under my subs and speakers but it is rated to the weight/load.

You can read all about it here.

Shock and vibration solutions | Sorbothane

This stuff is Load Rated at 240-480 lbs each. My Alon's are about 105 lbs each.

The discs are 2.25 inches in diameter and .25 inches thick. FWIW

thank you, great hint!

That's the secret so many people miss in trying to decouple with things and why things like foam rarely work.

I use 10 Neoprene pads under my cutting lathe to isolate it. Am thinking you could use them for bigger speaker setup they take about +/-700lbs on top. Just under 1" thick.

Thanks Tom, I've just ordered some from Amazon in the UK - for the price I would think they're definitely worth a go.

To my knowledge, if you have a solid base as you do you want a rigid
connection between your speakers and the base. Isolating the monitors only becomes beneficial if the floor is transferring cabinet vibrations.
If one really wanted to isolate speakers from the floor why not hang them from wires?

Any rigid material transfers sound. Granite blocks may dampen some HF (maybe even ultrasonic) due to their inertia, but they will still deliver other vibrations to the floor they stand on.

These speakers weigh about 105 lbs each. No way to hang them from the ceiling. This tweak works and I am very happy with the results. Thanks!

Also speakers hanging in space have a tendency to move around especially when a large bass note sounds so the imaging would be all over the place. No thanks! not for mastering...

FWIW.

Although hanging speakers in a mastering room can work (Ray Staff had small B&Ws on chains at Trident in the early 80s, for example) I haven't seen it applied to anything larger than a bookshelf-style box.

Northwood did something I think at Red Bull Academy. Springs and all.

another Northward studio, and the speakers are hardly bookshelfs !



Northward Acoustics - Systems

Looks very nice indeed, as do all the Northward designs I've seen.

I just built new stands for my monitors based around TNT-Stubby - A DIY Speaker Stand Project on TNT-Audio [English] with the difference being I built a cavity box for the top and filled it with sand that the top of the stand rest on. It really helped. I then placed .25" felt pads under each monitor. I've wondered how much the felt is really helping. May have to check these out. For the price can't really go wrong.

125 lbs is not that heavy, particularly for mastering monitors. I never liked the way speakers sounded when suspended by chains or wire. As for the gel pads,
you say you have a thick piece of granite and concrete floor, why would you want the cabinets to flex on the pads at all ? Better low end with rigid contact to your solid base, no?

You have to do what's right for a cabinet and surface it rests on.
I disagree about hanging monitors, I think they are fantastic and the imaging only slightly less accurate. They can't be free hanging like a plumb bob, they also need a "pull down"

Sorbothane is awesome stuff. A few years ago when I redid my space, I put an acoustic underlay made with the stuff between the concrete and laminate flooring. My Mastering speakers are on stands with spikes (had a few feet left and put little squares under each spike as well). I also use squares of it under my mixing nearfields (between some cheap Mopads and my desk) and at around 90dB SPL, I hardly feel any vibrations on the desk itself.

Thanks for sharing! - (acoustic solutions are always welcome)

I agree with Theknob.

Tried sorbothane - matched exactly to the weight of the speaker system - 50 durometer shore hardness and correct diameter, they were exactly right for the system. What I found was that the speaker moved like it was on jelly - this is for a stereo subwoofer positioned directly underneath the mains - each sub has 2 ten inch drivers, the sorbothane sucked the life out of the system - on heavy bass transients movement was clearly visible. Perhaps for bass limited systems it would be ok but I can't see how any enclosure movement can be good when a moving transducer is involved. It would be excellent for turntables though - no doubting sorbothanes vibration absortion qualities.

I must admit certain aspects of the sound were enhanced (though artificially) - I may be wrong but concluded it basically turns your speaker system into a compressor of sorts - with larger bass transients not as much air is moved as the speaker is moving backwards so to get the same loudness things have to be turned up. It could lead to inappropriate dynamic range processing.

Interresting, though i'm a bit in doubt if it will work with my 802's. I have them standing on 15cm thick concrete blocks of 60kg each. I think that 140kg is too much for the pads to survive.
Stumbled upon this BTW: Sorbothane Isolation: Sound & Vision | eBay

Because the cabinet will move itself if it's hung like a swing. It is the worst way to mount speakers.

The Northward rooms have the speakers under a lot of tension. There is no way they will move.

Sorbothane works great, using it now on a mono nearfield on a desk...
no desk vibrations at all.

Correct!

There is a minimum 3kN of pressure per unit (300kg / ca.670-680lbs)
The system is also equipped with custom made "Anti-kickback" decouplers (for lack of a better term) which are hidden within the boxes. Basically a pre-constraint system between the outer (coupled) and inner (decoupled) boxes so it can decouple at very low frequency while working in the horizontal axis, preventing possible residual movement in that axis.

There is no way the speaker can move.

Right. So why would one want them to move around on gel pads, unless they are on top of a boxy object like a mixing console?

I would say the most important fact has not mentioned yet. the resonances frequency of the whole system( spring, mass) has to be very low( under 20hz) to be effectiv in decoubling. in my understandig you need high mass on a soft spring. or a coupling to a massive concrete floor.
here in germany sylomer is the most known product for such tasks.

Absolute limit is 10Hz.

Preferably stay under 8Hz if you want good decoupling efficiency @ 20Hz, which is in fact the lowest figure Sylomer can reach in practice.

If your f(0) is 20Hz, then you resonate (amplify transmission) until ca. 28Hz and start being somehow efficient from only ca. 35Hz. That's overlapping too much with the speaker response in the LF. And can cause nasty side effects.

Hence the use of springs for this application whose f(0) can be pretty close to 4Hz in our case, often used in conjunction with Sylomer buffers - or equivalent, as springs are not efficient in the midrange and high frequencies.

Sorbothane is NOT a gell. See this for a quick discription http://en.wikipedia.org/wiki/Sorbothane