Question on specific room treatment

[PoliticalBonobo]

Here is the layout of my room. The ceilings are 7.5ft high. The treatment in red is already completed (or soon to be completed). The red panels are 4in-thick 4.0pcf Thermalfiber safing mineral wool.

What I'm wondering is this: would there be an issue in using 2in thick panels (shown in green) instead of 4in thick? I don't want to use 4in thick if I don't have to, and all of that area is behind the listening position.

[Sam Spoons]

2" thick panels will not absorb lower frequencies as well as 4" (or 2" panels spaced 2" from the wall which work pretty much as well as a solid 4" panel) but the difference won't be huge.

Why do you want thinner panels?

Also looking at your plan you should already be hearing a huge improvement compared to the bare room but, given the size, some more bass trapping would be my next step.

[Music Wolf]

As Sam says, spacing the panels off the walls will extend their low end usefulness (same applies to the 4" panels). I can't see a door on the diagram but, if it's not in the way, you may be better off putting panels across the rear corners.

[PoliticalBonobo]

Why do you want thinner panels?

Purely for cosmetic and space-saving reasons. 2in isn't necessity though, so I'll just keep things going with 4in thick. It's probably also worth mentioned I have all the 4in panels about 2in from the wall.

Also looking at your plan you should already be hearing a huge improvement compared to the bare room but, given the size, some more bass trapping would be my next step.

Any suggestions on that? I was going to put floor-to-ceiling, membrane traps in the front wall corners (pictured). But beyond that it'd be very difficult for me to insert bass traps in wall-ceiling corners or anywhere else.

[PoliticalBonobo]

As Sam says, spacing the panels off the walls will extend their low end usefulness (same applies to the 4" panels). I can't see a door on the diagram but, if it's not in the way, you may be better off putting panels across the rear corners.

Yeah, I actually do have the 4in clouds and wall panels about 2in off the wall, so that should help.

I could trap one back corner, but the other is unfortunately where an open doorway is (will be putting door there eventually).

[Matt Houghton]

Lots of other sensible advice here already. But I'd add that, if possible, it's worth hanging the clouds in such a way that it's easy to move them up and down later. That way, you can adjust their position once you've figured out how the room actually sounds when treated (and can, if required, raise them right up to the ceiling if you need to use the space for things other than critical listening!).

[Sam Spoons]

I have bass traps in both front corners and in a alcove behind the monitors (speakers and computer). I haven't done any proper tests yet but the room sounds reasonable (especially compared to it's mostly untreated former self). Remember that too much HF absorption will make the room sound dull or boxy so don't overdo it (diffusers are useful to prevent this, you bookshelf will work as one for starters).

[PoliticalBonobo]

Remember that too much HF absorption will make the room sound dull or boxy so don't overdo it (diffusers are useful to prevent this, you bookshelf will work as one for starters).

Thanks, Sam. I left about 15in of bare wall between each cloud shown and have yet to do anything with the space on the ceiling near the front wall (in front of the desk). Thoughts on putting foam diffusers in those spaces? Or just leave bare to avoid over-treating?

[Sam Spoons]

If you have the room I believe diffusers are a good way to reduce standing waves without reducing high end.

I haven't heard of foam diffusers though, the point of diffuser is that the still reflect but break up (diffuse) the reflections.

https://www.youtube.com/watch?v=oHTmNyo_0O0

[PoliticalBonobo]

I haven't heard of foam diffusers though, the point of diffuser is that the still reflect but break up (diffuse) the reflections.
https://www.youtube.com/watch?v=oHTmNyo_0O0

There are foam panels with diffusing "shapes" on the surface, but I see how a foam diffuser wouldn't work!

Do you think a couple hemispherical diffusers (like the one you linked) would work will on the ceiling space near the front wall, in front of my listening position?

[Sam Spoons]

I don't know I put my studio together based on a fair bit of reading, asking loads of questions on here and a moderate understanding of the principles. It seems to have worked for me in so much as it is a huge improvement on what I had before but I haven't used any diffusers 'cos the room is very small (little more than half yours) so couldn't give any useful advice.

[Drew Stephenson]

Personally I'd start with the stuff in red, then pause and take stock. Is it too dull? Too bright? Have you got hotspots that need tackling? Etc etc.
No point planning more work than is necessary.
Apart from bass trapping, you can never* have too much bass trapping.

* well, in any normal sized room.