Ceiling Cloud Placement: S400 MKII in a 9m x 4m Room with Beams

[oneofakind]

Hey guys,

I just ordered 9 GIK acoustic panels (24" x 48" x 2") and I’m planning to use 6 of them for a ceiling cloud.
My room is about 29.5' x 13.1' (9mx4m) with a pretty low 7.5' (2,30m) ceiling and exposed wood beams.

I'm using Buchardt S400 MKIIs, miniDSP Flex and Ncore NCx252MP amp and I sit about 7.9' (2,40m) back.

I definitely want to hit the first reflection points, but I’m not sure about the best layout:

• Should I just mush all 6 together into one giant "super-cloud" (like a 3x2 block)?
• Or is it better to space them out – maybe 4 in a square and 2 further forward over the speakers?

The goal is to clean up the imaging and get rid of some "harshness" I’m hearing.

Thanks!

Here is my room:

i thought best placement would be something like that:

 

[oneofakind]

Ah and here are some measurements of my room:

 

[Waveform Fidelity]

I did a similar thing recently. Most recommendations are to place gaps between each panel - mine are 1/2 panel gaps. The other thing that is important for maximum attenuation is to suspend them with an air gap to the celiing - I used 3 inches.

The reason why a gap is better (in case you don’t know) is that the attenuation (power loss) is caused by slowing down the sound waves (particle velocity). If you fit the panels on the reflecting surface, where the velocity is zero there is little attenuation both when the wave enters and leaves the panel on reflection. If you separate the panel from the reflecting surface, energy is removed from the incident wave as its velocity is still high and then on reflection (where the wave passes back out of the panel) it is attenuated again.

In your picture you could arrange the panels to be flush with the beams (fit between beams) by suspending them. That might help with aesthetics.

Did you measure the RT60? - that’s the time it takes for the reverberant energy to decay by 60dB - before and after is worth doing. Mine was 490 milliseconds and I reduced it to 355msec (my room has 18ft ceilings and a stone floor)

Let us know how it goes

Ps you can use ARTA for RT60 measurement - its now free of charge.

 

[kemmler3D]

Based on where you are sitting, the back wall is probably a bigger problem than ceiling bounce. A friend of mine has those speakers (or similar, can't remember exactly) and also sits next to the wall like that, and I noticed some mid-range harshness / peakiness that I attributed to seating position at the time.

Maybe do 4 panels for the cloud at first reflection and 2 on the wall?

Based on your measurement my guess is you will experience an improvement in mids but the treble might be too subdued. Maybe consider using a binary diffuser facing on some of the panels to help with this.

 

[oneofakind]

The reason why a gap is better

Thanks for the advice!

Regarding the air gap, I’m mounting the absorbers underneath the beams because one of my reflection points is right on the first beam. This actually creates a natural air gap of about 6 inches between the panels and the actual ceiling, which should work great for attenuation.

I'm just not sure how to arrange them. One big cloud in the middle of the room or not.

RT60 from REW

 

[oneofakind]

Maybe do 4 panels for the cloud at first reflection and 2 on the wall?

I have a really thick acoustic curtain on that window on the left now and i'll put absorbers on the wall next to the window.

 

[Waveform Fidelity]

Thanks for the advice!

Regarding the air gap, I’m mounting the absorbers underneath the beams because one of my reflection points is right on the first beam. This actually creates a natural air gap of about 6 inches between the panels and the actual ceiling, which should work great for attenuation.

I'm just not sure how to arrange them. One big cloud in the middle of the room or not.

RT60 from REW
View attachment 507828

BTW - I forgot to ask whether your panels have backing on them or open fibre? With a backing panel the benefit of a gap is irrelevant

 

[oneofakind]

BTW - I forgot to ask whether your panels have backing on them or open fibre? With a backing panel the benefit of a gap is irrelevant

Those are the ones i ordered for the ceiling: GIK Acoustics acoustic Panel
They're open as far as i can tell