DIY Basstrap Question

So I've been looking at all of the DIY Basstrap topics and I must say it looks really easy and I'll be able to save a lot of money this way, so I ordered Roxul Rockboard 60 Case of 6 from http://www.atsacoustics.com/item--Roxul ... -RB60.html and I found the best price on burlap at http://www.hancockfabrics.com/product--9186.shtml But have not ordered that yet because I'm trying to figure out how much I will need. Anyway I noticed on all of the topics with the people making these, that they do not completely cover the back of the bass trap, is there a reason for this? I thought the burlap was to keep the insulation particals from escaping because you don't want to breath that in. And if there is supposed to be a gap between the bass trap and wall I see that being a problem. So i'm just wondering if there is an acoustic purpose to leave the back open or if it's just done to save money because nobody sees the back. thanks! -matt

There is no need to seal the back. The fibres do not spread if the material is not not moved. The fabric is for esthetics, not acoustics. Andre

Thanks but if i do seal the back it won't effect the performance?

Matt Whritenour wrote:

Thanks but if i do seal the back it won't effect the performance?

Correct. Andre

thanks!