Decoupling Monitors from Floor

[Cojonesonasteek]

I live in a duplex and want to set up a small editing/mixing space in an upstairs bedroom, approx 15x12 with 9-1/2' ceiling. The floor was built so poorly that you can bounce up and down and the whole room shakes.

I used to live in the next door unit so I know from experience that only the low end transfers through the common firewall. But just to be considerate to my new neighbors, what can I do to decouple the monitors from the floor to reduce LF transmission?

[trumpetgunk]

Look at a product from Auralex called the "GRAMMA" or the "Subdude". I live in an apartment and use one underneath my subwoofer. For $50, it reduces the vibration from the subwoofer nicely. It, of course, doesn't reduce the output level of the sub but rather just decouples it from the floor.

[Professor]

Yeah some of the Auralex stuff like MoPads and GRAMMA would work pretty well. You could also raise the speaker stand up on points (little spikes that reduce the contact points with the floor) or you could find some sand-fillable speaker stands and actually fill the tubes with sand. The sand dampens vibrations before they reach the floor, and the spikes minimize the transmission area to the floor. A home hifi wire company called Audioquest also makes various styles of sorbothane rubber feet which are about an inch or two thick and kinda like firm silicone that can decouple speakers from stands (if you're not using sand-filled stands).
And depending on the nature of the space, you might consider adding some dense material to the floor to stop the floor from vibrating. I'm not talking about laying down tile or anything, but something like an old mattress placed directly on the floor, especially near the speakers (maybe behind them) could help. If the setup is in your bedroom, place your bed directly on the floor instead of up on a frame, if you can.
Decouple & dampen - that's the key.

-Jeremy

[trumpetgunk]

You could also raise the speaker stand up on points (little spikes that reduce the contact points with the floor) ...

Putting the speaker (or speaker stand) on spikes actually works to couple the speaker with the floor and helps the vibration transfer to another room.

If you're looking at cheap hi-fi decoupling tricks, bicycle innertubes and racquetballs sliced in half have also been used to decouple components and reduce vibrations. Success varies, try at your own expense. I personally tried the racquetball approach but the GRAMMA was much more effective.

Jason

[Cojonesonasteek]

Thanks for the great advice. I have a couple sand-filled monitor stands that I haven't used in years...I'll try to mount something on the bottom of each stand (just a flat wood panel right now) to get even more damping.