Category Archives: Interesting facts
Reverberation time and room acoustics
You can very easily understand what reverberation time is by clapping your hands and listen to the echo and how it fades. The time it takes for it to go away is the reverberation time. When we talk about reverberation time we often mean the T60, which is the time, in seconds, it takes for […]
If printed pictures would be accompanied with sound
One thing strikes me after reading architects and interior decoration magazines for several years. On almost every picture displayed there is a neutral white smooth seamless ceiling. This is no coincidence. The natural smooth seamless ceiling is chosen because it doesn’t interfere with what the designer believes to be important regardless of whether it is […]
Fellert acoustical ceilings on curved surfaces
Fellert’s way of using unfaced absorbent boards which can be installed directly to a suspension grid or glued to various backings such as GWB, concrete etc. makes it especially suitable for curved surfaces. Most ceilings needs some sort of special arrangements in order be suitable for curved ceilings. Making a special arrangement basically means that […]
Sound class and weighted alpha
As well as ASTM has its terminology on how to express the absorption of materials and how to define this, the International standardization organization ISO got one as well. When ASTM talks about NRC to express the sound absorption of a material, ISO talks about Sound class and weighted alpha. NRC is explained in a […]
NRC, weighted alpha value, sound absorption class, what does it really mean? pt 2
Acoustical ceilings are very often accompanied by mystic terms and expressions but what is really the practical use of all these expressions and how do i know how it will affect my sound environment. In the previous post we tried to explain Sound absorption. If you missed it, catch up here. Let’s see if we […]
NRC, weighted alpha value, sound absorption class, what does it really mean? pt 1
Acoustical ceilings are very often accompanied by mystic terms and expressions but what is really the practical use of all these expressions and how do i know how it will affect my sound environment. Let’s see if we can make some sense out of all this and let’s start with the expression sound absorption: Sound […]
Fellert wishes you all a happy midsummers eve
Tomorrow at the 22:nd of June, it’s time to celebrate the midsummers eve here in Sweden. This is probably one of the more important festivities for us and everywhere you look people are getting reedy for the big feast. Children are collecting flowers for their flower wreaths and the young people are planning on how […]
The launch of Fellert Even Better
The new Even Better product line is now officially launched. A monolithic ceiling that can be seamlessly installed in areas of 1000 m2 or more without having to break up the smooth monolithic look with ugly expansion joints. A monolitic ceiling, only 43 mm thick, that can be shaped, colored and textured anyway you’d like. […]
Swedish national day
Today, the 6:th of June we are celebrating the Swedish national day. We all count on that you will support us by eating meatballs, wait patiently in line when queing and tries to do everything “lagom” much.
What you see is what you’ll get
2-Methyl-2H-isothiazolin-3-one, 1, 2-Benzisothiazoline-3-one, does that sound like ingredients you’d like to find in your morning cereals? – I don’t think so. Most of us are quite aware of and rather picky about what we eat. Strange ingredients added which we can’t identify and can’t understand the purpose of them being there normally makes the alarm bell […]