size of broadband absorbers

I have a question. What is an optimal size of fiberglass panel. I see, that almost everyone ( me to ) use panels, which size is standard 1m x 0,6m. I read in Everest, that one 10 m2 panel is less effective than ten 1 m2 panels. I mean that due to room an budget ( time ) conditions, it sometimes seems wiser, to build one huge panel, that will cover whole ( or half of the )wall.

If the panels are placed adjacent with no space between them, and the edges are not covered with reflecting material, then there's no difference between many small panels versus one large panel. But when there are spaces between the panels, the edges add to the total absorption. This is explained in this article:

Alternative Test Methods for Acoustic Treatment Products

Especially see Figure 2.

--Ethan

------------translation:
Jeśli panele są umieszone tuż przy sobie bez żadnych przerw pomiędzy nimi oraz ich krawędzie nie są pokryte surowcem odbijającym dźwięk, wtedy nie ma żadnej różnicy pomiędzy jednym wielkim panelem a wieloma małymi. Jeśli jednak są pomiędzy nimi przerwy, wtedy krawędzie panelu zwiększają sumaryczną absorpcję.

So, the best solution is to have more absorbers and mount them in a distance to wall ??

It depends what you need to accomplish. You didn't distinguish between corner bass traps and general mid/high frequency absorbers. I don't think it's possible to have too much bass trapping, but you can definitely absorb too much at higher frequencies. Also, the ideal amount of HF absorption depends a lot on the size of the room and whether it's for recording, or mixing, or both.

--Ethan

Well, I read that good solution for more absorbers and less HF attenuating is fiberglass built in reflecting material. Some guys say, that building fiberglass in foil, lowers the absorption frequency, making it less afective to high frequencies at the same time. Are those guys right ?? ( and also me )

Yes, adding foil or paper or thin plastic increases bass absorption and also reduces absorption at higher frequencies. This article explains more and shows the results I got for three densities of fiberglass with and without a paper facing:

Density Report

--Ethan