If you enter the search term "vibrating bed" in Google, you mainly find search results about sleepless nights or even symptoms of illness. You may not find many hits in terms of solutions, mainly because there are not a lot of practical solutions to solve this problem. On this page we will provide an explanation about what may cause this vibration. That is, physical vibration, not sound (airborne noise).
Potential sources of vibration
Most sources that transmit resonance/vibration are not or difficult to detect, because they are often located further away from the bed than you might think. Extremely low frequencies, both contact and airborne noise, consist of long waves and contain a lot of energy. Therefore, it is not impossible that part of the resonance comes from a source that is located a few hundred meters away. Common sources of vibration are sewer pumps, industrial machinery (from nearby companies), metro, tram, or train tracks and freight traffic. Alternatively, a low groundwater level can also be to blame (low frequencies is to say vibrations with a frequency below 100 Hz).
Real-life solutions to low-frequency contact noise problems
A customer emailed us about a problem regarding low-frequency vibration that she could sense in her bed. The problem was that serious, that she had been sleeping badly for over a year. Because we hear about this problem more often, we came up with the following solution.
In order to insulate low-frequency vibration, a certain type of vibration insulation is needed, the bed must be placed on a kind of dampers. The product UniDamper Basic is extremely suitable for this problem. The number of dampers required depends on two things: the load per damper (meaning the sum of the bed's weight plus persons) and the frequency of the vibrations (often unknown).
Since in most cases the vibration's frequency remains unknown, you will need to experiment with the number of dampers underneath the bed. Most likely, you will need at least three dampers per bed leg (totalling 3 sets, 4 dampers per set). Depending on the problem, you will have to experiment with one or two extra UniDampers per bed leg. For a correct application, you need to place a plate that distributes pressure, for example MDF, between the Unidampers and the legs of the bed. This plate ensures pressure distribution across the surface of the damper and stability of the bed. Dimensions of the plate (to be provided yourself): (l)150 x (w)150 x (d)12 mm, so slightly smaller than a UniDamper, preventing sharp parts from protruding.
When experimenting with the application of the UniDampers to achieve an optimal result, you can assume two things:
• The lower the frequency, the more dampers you will need.
• The more suspension travel, the better (low) frequencies are isolated.
Points of attention
If your bed has more than four legs, place the same number of dampers under each leg. With each damper, the bed becomes about 25 mm higher. Make sure that the bed cannot slide off the dampers and that the bed is stable. The plate between the bed legs and the dampers should not bend and should not protrude, avoiding sharp edges.