My studio needs bass traps in the corners.

I had an idea about how to make 'cheap', quick and easy bass traps, please give me an opinion:

Materials:
24 x single wall cardboard boxes 600 x 600 x 600mm
Several packs of Knauf RS45 Rock slik (100mm x 600 x 1200)

To make:
Cut the RS45 into 600x600x100 pieces and fill the boxes (i.e. 6 pieces)
Pile up 4 boxes in each corner of the studio (2.4m high)

It seems to me that this creates stackable chunks of RS45 so it avoids sagging. You don't have to make wooden frames or cover with fabric, and by having a cube shape you have twice as much trap as the standard triangle shape. Also I could probably make 16 cubes (4 in each corner) in about 30 mins.

The cardboard will reflect some high frequencies I suppose, but other than that does this seem like a good idea? It seemed to me like it was an easy solution.

What do you reckon?

Never tried it but it should work. I guess if you want you can always cut out the front and back. Here is a test we did with wood frames if you go that route.
DIY Acoustic Panel and Bass Trap Frames |

Hi Glenn

Thanks for your reply. I looked at your link, interesting thanks. I wonder if cutting out the front and back would weaken the boxes too much, but I won't know till I make them. I considered using a large hole saw (4 inch) to make some holes. Could look quite funky too.

BTW I notice that lots of people recommend the 703 and 705 rigid fibreglass but here in the UK I can't find it and I can't find any equivalent. Do you think stacks of 600mm cube fluffy Knauf RS45 will have similar bass absorbtion? Would the cubes be best against the wall or pulled away to leave an air gap?

Thanks
Ted

When they are that thick you want to use the less dense fiberglass.

I like this idea, especially cutting holes in the front and back - if you need additional support you could put dowel rods on the inside corners, yea? Then wrap the whole bugger in burlap and it doesn't even look ghetto!

The Knauf RS45 would definitely meet what you want. Make sure you get the ECOSE stuff though, the binding agewnts have had all the nastiness taken out - Greensafe - GIK Acoustics

An update! So all the Knauf RS45 arrived today (i think i might have ordered too much, can you have too much??) - see jpeg.

As a quick test as the cardboard boxes haven't arrived yet, i piled the wrapped RS45 in the corners. - see jpeg2

It already sounds miles better - i can hear the distinction between sub-bass and kick drums now.

The packs are compressing a 500mm pile (5 x 100) down to about 400/450 so the rockwool is a bit denser, + it has the plastic on.

What am I losing by having it left wrapped up? I know the plastic will reflect the highs a bit.

Also is it true that you have to have the rockwool edge on to work best?

Ted

Out of the plastic it will expand a bit more which is a "bit" better, but having the plastic on will reflect some of the upper energy (a good thing). I would stack some of it behind you sit. No, stack A LOT OF it behind where you sit.
40Hz, go to hell!

Thanks
I have the same amount of RS45 behind me that you can see here in front, plus a fairly large area of ceiling cloud to hang above the desk. 17 packs total!

Is there is an advantage to having the rock wool 'edge on' to the listening position? As opposed to flat surface facing listening position?

Not really following what you are saying...

One thing about the plastic that I did not point out is you do NOT want them with plastic in the early reflection points.
Video Early or First Reflection Points - GIK Acoustics

Is there is an advantage to having the rock wool 'edge on' to the listening position?

Can you expand on this?

That's impressively ghetto. How did it work out for you? I know this is an old thread.

Years fly by! Yes it all worked fine, still in use - I'll take some pics to make it clear how it turned out. Not sure I'd recommend this method though, it probably would have been almost as easy just to build a framework for the rockwool.