shaman´s absorber build thread

[Shaman]

Hi there,

Some time ago I thought my control room could need some accoustic enhancement in the area of general decay time which was a bit too long + there were some disturbing high frequ. reflections at my mix position since I´m having parallel walls and a pretty small room.

When I was looking around for absorption pannels the products either were

1, insanely expensive or
2, REALLY ugly ( I hate grey foam)

- so after a while of meditating on my accoustical & aesthetical needs I had an idea, which I want to share with you since it

1, sounds great -
2, looks great and last but not least
3, is very affordable.

First we need to buy some frames for our absorbers.


I found some which are about 4cms deep at IKEA.
They are available in several wood colours and in many sizes.

In my case I bought the 40 x 50 cm version in birch wood.

[Shaman]

First remove the paper passpartout + glass from the frame - all we need is the frame + the wood rearpannel.

[Shaman]

As absorption material I´m using good old mineral wool from the hardware store.

I used 4cm thick URSA mineral wool.
For cutting a bread knife comes in handy.

[Shaman]

Take the wooden rearpanel of your RIBBA frame and cut the mineral wool along it with your knife.

[Shaman]

Insert the tailored mineral wool piece into the frame from the rearside

[Shaman]

Cover the rearside with the wood pannel.

[Shaman]

Fix the rearside with a staple gun to the frame - like this

[Shaman]

For the frontside I´m using felt fabric 1mm thick which

1, has a relative open surface structure and
2, is available in MANY, MANY beautiful colours and
3, fits very well on the surface of the mineral wool due to its rough and tight structre - there´s no violent pasting or whatever complicated technique necessary to fix the fabric on the wool.

[Shaman]

Again I´m using the wood frame rear side to cut the fabric into the right shape.

[Shaman]

Finally I´m fixing the frames on my studio control room walls with little wood screws and insert the felt after that into the frames, which is very easy and needs just a bit stretching here and there.

[Shaman]

Room sounds much tighter now (though not dead since I´m still having reflecting wall bits between & around the frames), decay time is where it should be + it looks pretty nice too.

Price per 40x50 cm module incl. all is ca. 20 Euros

[Shaman]

My absorbers even have their own serial nr. hrhr
Cheers

[Chris]

Those are damn nice looking. I live by an Ikea. I might make a few.

[jindrich]

Johannes,

Großartige Idee, nicht nur für Akustik sondern auch um alle Räume des Studios zu dekorieren, aber wäre es nicht besser gewesen den größeren Bildrahmen benutzt zu haben? Danke für den Tipp jedenfalls.

By the way, seems you made quite a notorious gear clean up and went down to basics, didn't you? Also seems you removed all racks from the floor to put them on the table; don't they interfere with the Questeds' sigth lines now?

[tidepool]

Those look very nice, great work. As an alternative, I bought 8' pieces of 1 x 4 lumber, and cut them down to 6'. I then screwed and glued together simple rectangular 2' x 6' frames. The fiberglass and fabric part are very similar to your approach, except they have no backs, not necessary. They are held on the wall with eyehooks/picture hanging wire. With this simple project, there was no waste, and is cheaper than the Ikea pre-built frame method.

[greatgreatriver]

Looks great - I don't understand how you got the felt fabric to stay on the mineral wool.

Thanks for sharing!

[cubivore]

yeah, please tell how you affixed the fabric.

[blaugruen7]

cool "absorber-workshop"
greetings

[Shaman]

Originally Posted by jindrich

Johannes,
Großartige Idee, nicht nur für Akustik sondern auch um alle Räume des Studios zu dekorieren, aber wäre es nicht besser gewesen den größeren Bildrahmen benutzt zu haben? Danke für den Tipp jedenfalls.

Hi jiindrich,

I actually used the bigger frames for the "drum corner" of my recording room - especially on the hihat side to avoid those nasty early reflections.

My concept for the control room was more a mixed pattern from absorbtion and reflection. I experimented alot and through having more wall space between them the smaller frames create a nicer spatial image in the end. Too big areas of absorbtion easily make the room muddy.

The very small frames ( say 10 x 5 cm) would have been even better -creating allmost some kind of diffusion but this would have been a lot more work.

2nd reason for the smaller frames is visual - many small elements make a small room look bigger than little big ones...

Originally Posted by jindrich

By the way, seems you made quite a notorious gear clean up and went down to basics, didn't you? Also seems you removed all racks from the floor to put them on the table; don't they interfere with the Questeds' sigth lines now?

Right, less is more in the end.
I find myself using more and more the same stuff (gml + neve) and if I need something else the other day I eventually use...errr gml + neve hrhr..

I removed the side racks cause I found it really strange to tweak things not being in the sweet spot.
Now everything is in hands reach - right the one rack is a bit near the left quested - doesn´t make much of a difference since tweeter still is in sightline.

[Shaman]

Originally Posted by greatgreatriver

Looks great - I don't understand how you got the felt fabric to stay on the mineral wool.

Sorry - this is missing since it´s a bit of an artistic act to fix the fabric with one hand and taking a picture of it with the other LOL
but I tried to make some pictures for you...arrrgh

First I fix the frame with screws on the wall and adjust balance and position.

Then I simply press the fabric into the sides of the frame.
Since the mineral wool allready has a bit of tension from the fixed wood rear wall it easily fits.
I found that ROCKWOOL is even denser than Ursa wool and gives the fabric even more tension to fit.

This method has the advantage that

1, No particles of the mineral wool can escape (neither from front NOR from back - a big one - mineral wool particles are PITA for gear AND health) and
2, If you are tired of the colour after some time you easily can applicate some different fabric without having to remove the frame from the wall.

[Shaman]

Applying the fabric nr. 1

[Shaman]

nr.2

[Shaman]

nr.3 ...et voilá

[greatgreatriver]

Shaman you are great! Thanks a lot bro. You are so creative and you make everything look like art! Keep it up...

[TheSweetener]

Very nice and professional looking absorbers!
As you all know musicians tend to touch every absorber they see. Since the fabric is not fixed I'd expect them to "ooops, I just pulled out that green stuff"

It's a shame there are no deeper frames! They're all 4 cm right?

Shaman, which fabric did you use?

[Tommylicious]

Thanks for sharing Shaman, they look super!

[Spyrow]

Originally Posted by TheSweetener

"ooops, I just pulled out that green stuff"

hahahahaha that was funny!

[Shaman]

Originally Posted by TheSweetener

As you all know musicians tend to touch every absorber they see. Since the fabric is not fixed I'd expect them to "ooops, I just pulled out that green stuff"

hrhr, the fabric sits surprisingly quite tight due to the fact that the rockwool is "compressed" a bit by the fixed rearpannel.
Also the surface of both materials, mineral wool and felt both is a bit rough so they sit very well on each other and don´t slip.
I can´t guarantee it works with any other material than felt but this combo really works great !
Not tight like a distressor on nuke more like an 1176 on 4:1 but it sits well in the end.

Originally Posted by TheSweetener

It's a shame there are no deeper frames! They're all 4 cm right?

Right 4 cms deep. Absorption is mainly in the higher frequs and not in the mids with this depth.
After all it´s an affordable solution.

I thought about different ways but everything else means you need an additional inward frame around you wrap the fabric and is way more complicated.
The most idfficult part to find is the frame...but as I think a bout it - one could eventually paste two frames into one for a greater overall depth which in this case would be 8 cms...hm

Originally Posted by TheSweetener

Shaman, which fabric did you use?

Felt

[Groff]

Cool idea. Looks good!

[TheArchitect]

Very Cool. I wish the rigid insulation was available more readily in the box stores around here. Its more than a chore to find a source and arrange for shipping.

I did something very similar but used 6 inch deep frames filled with R19 insulation\

http://members.toast.net/dwyss/pics/Room1.jpg
http://members.toast.net/dwyss/pics/Room2.jpg
http://members.toast.net/dwyss/pics/Room3.jpg