John Sayers' Recording Studio Design Forum Archive

Hi everyone,
I'm new and this is my first post I would like to improve my room acoustics.
This room was the bedroom of my wife and... now wife sleeps in the living room ...Praise the Lord

Front and left walls are thick heavy, structural, but right and rear walls are 9 cm thick.
Now I have :
- in the front corners - Superchunk
- first reflections - absorbers 120x200x10 with 5 cm AirGap
- rear wall - 20 cm AirGap and 10 cm absorbers to a height of 200cm


I thought about flush / soffit but I think it is impossible - the window.(Am I wrong?)
Measurements done 168 cm from the front wall speakers in triangle, sub on the windowsill (30 cm off axis).
Speaker system Adam Audio S2.5a + Sub 10.

https://www.dropbox.com/s/6ib8q0z1lib47 ... .mdat?dl=0


Celling is clean.

I would like to make hangers across the rear wall.
Maximum space is 48 cm - to the door.

What size should have hangers?
How should they be hanged?
(parallel to the rear wall,
perpendicular, an angle?)
They have to be the same dimensions or different?
Which will be the best osb 6mm, 12mm or 18mm?
Can I use insulations like a dacron(300g/m2) ?
Is hangers good idea for my room?

What should I do on the ceiling?

Thank you in advance for your help,
horhenjusz

Hi "horhenjusz". Please read the forum rules for posting (click here). You seem to be missing a couple of things!

Front and left walls are thick heavy, structural, but right and rear walls are 9 cm thick.
- in the front corners - Superchunk
- first reflections - absorbers 120x200x10 with 5 cm AirGap
- rear wall - 20 cm AirGap and 10 cm absorbers to a height of 200cm

Please post photos of those, and of the room in general.

I thought about flush / soffit but I think it is impossible - the window.(Am I wrong?)

Without seeing photos of the room, it's hard to say,but it looks like you do have space there. I have developed a modified "Z" shaped soffit that helps in those circumstances.

Measurements done 168 cm from the front wall speakers in triangle, sub on the windowsill (30 cm off axis).

Where are the speakers located in the room? Distance from front wall ( side wall / height above floor / angle) How are they mounted?

I would like to make hangers across the rear wall.
Maximum space is 48 cm - to the door.

That's enough space. Tight, but enough. Angle the hangers quite a bit, so they still have good surface area.

What size should have hangers?

Almost as tall as the room, just leaving a 10 or 15cm gap underneath, and enough gap at the top so they can hang freely (maybe 20cm, or less). If you hang them edge-on to the room then they can only be 48cm deep, max, but if you angle them then you should be able to get them to 60 or more.

How should they be hanged?

Use wire to hang them. Each one is not very heavy.

(parallel to the rear wall, perpendicular, an angle?)

Angled, but closer to perpendicular.

They have to be the same dimensions or different?

They can be different. I normally make the ones in the corners deeper, and the ones in the middle shallower.

Which will be the best osb 6mm, 12mm or 18mm?

Not! Don't use OSB, It is far to dense. Use "Homasote". It is a very soft fiberboard, light weight, not dense. It's the type of board that is used for "bulletin boards", where you pin up notices with push-pins. You cannot use heavy, dense board for this. This is what it looks like:

Can I use insulations like a dacron(300g/m2) ?

I'm not familiar with the acoustic properties of that. I would use fiberglass insulation that has a density of about 30 kg/m3 or a bit less, or mineral wool insulation that has a density of 50 kg/m3 or a bit less.

Is hangers good idea for my room?

Yes!

What should I do on the ceiling?

I would do a hard backed ceiling cloud, hung at an angle, over the area between the mix position and the speakers. You might need more treatment further back as wll.

The REW graphs look quite good, except for the big modal problem at around 37 Hz, which is definitely your 1,0,0 mode (first axial mode in the front-back axis.


- Stuart

Stuart,

thank you very much for your reply. I made pictures, if you need more, please let me know.

I have to apologize because I made a mistake in the description, I hung on the ceiling 4 light(4cm) panels (foto). Sorry ..

Measurements done 168 cm from the front wall speakers in triangle, sub on the windowsill (30 cm off axis).

Where are the speakers located in the room? Distance from front wall ( side wall / height above floor / angle) How are they mounted?

101 cm from to the side walls,and 45cm from front wall to cone of speaker. Speakers stand on metal stands, height is 117 cm (to the tweeter).

Behind the speakers is space for little panels.

If I do hangers of rear , it is necessary to make wall of mineral wool before hangers?

Please read the forum rules for posting (click here). You are still missing something!

101 cm from to the side walls,and 45cm from front wall to cone of speaker.

Bring them a bit closer together: Make it about 95 cm from the side walls (that's the location of the acoustic axis! Not the side of the box). That means the speakers will be 153 cm apart.

Behind the speakers is space for little panels.

height is 117 cm (to the tweeter).

That's a little low. Move them up a bit, so the acoustic axis (not the tweeter!) is about 122cm above the floor. Are those A7X speakers? They look like it. Or maybe A8X.

ROOM3.jpg

Your mix position is about right (168 cm from front wall), but your speaker angles are not optimal. Set up a vertical pole at about 208 cm from the front wall (about 40cm behind your head) and aim the speakers at that pole. The acoustic axis of each speakers should be aimed at that pole.

Also, put the sub on the floor, on an isolation pad.

You are going to need much deeper treatment on the rear wall. I would suggest Superchunk bass traps in both vertical corners, very deep and wide, and also across the top (wall-ceiling corner), plus deep absorption across the rest of the wall. On the front wall, you can do a horizontal superchunk in the floor/wall corner, and fill in more insulation behind your existing corner bass traps. Use light fluffy insulation, such as 20 kg/m3 fiberglass, or something similar.


- Stuart -

Hi Stuart,
I will try to be a better student. If I made mistakes, then I will ask for your understanding
Below overdue information:
Goal: to create a mixing / production room.
Apartment is located a block of flats on the first floor (2 storey building).

Construction: Unfortunately I do not have the specifications, but it looks like this:
Celling and floor-concrete
Front and left walls - heavy, structure
Right and rear walls - 9cm of airbrick
Floor is cheap wood laminate.
Door - fibreboard with glass
Window on front wall

Listening levels 75 DB SPL C weighted

Monitor system: Adam audio s2.5a + adam audio sub 10

Stage: Superchunk on the front corners, 19 movable panels (100x61x10cm with 5 cm airgap):8 for side walls, 10 panels - rear wall, 2 little panels for speakers, 4 very light (ecophon - 4cm) panels hanging from the ceiling,
extra unused 3x 1/4 cylinder foam 90kg / m3.

measurement devices: Apogee Duet, Earthworks QTC 50

Budget: 500-1000 USD

Bring them a bit closer together: Make it about 95 cm from the side walls (that's the location of the acoustic axis! Not the side of the box). That means the speakers will be 153 cm apart.

I did 95cm from side walls, 45 cm from front wall.

That's a little low. Move them up a bit, so the acoustic axis (not the tweeter!) is about 122cm above the floor. Are those A7X speakers? They look like it. Or maybe A8X.

I moved them up, now is 122 but to the tweeter. From the manual of Adam S2.5A: "Tweeter should be positioned approximately at the height of your ears. "
maual link
Is it a good height, if I need to change?

ROOM3.jpg

Your mix position is about right (168 cm from front wall), but your speaker angles are not optimal. Set up a vertical pole at about 208 cm from the front wall (about 40cm behind your head) and aim the speakers at that pole. The acoustic axis of each speakers should be aimed at that pole.
Also, put the sub on the floor, on an isolation pad.

Done. Isolation pad - 4cm (ecophon).

You are going to need much deeper treatment on the rear wall. I would suggest Superchunk bass traps in both vertical corners, very deep and wide, and also across the top (wall-ceiling corner), plus deep absorption across the rest of the wall. On the front wall, you can do a horizontal superchunk in the floor/wall corner, and fill in more insulation behind your existing corner bass traps. Use light fluffy insulation, such as 20 kg/m3 fiberglass, or something similar.

Can you me a hint what will be better on the rear wall of mineral wool or hangers? What worries me is big axial mode.
Should I do first ceiling or rear wall?



Measurements in new settings(speakers 95cm from the side walls, 45 from the front wall,angled to the 205cm from the front wall, mic position 168 cm from the front wall) - sub on the floor and sub on the windowsill
download link

2 little panels for speakers,

They need to be a lot bigger than that, and thicker.

very light (ecophon - 4cm) panels hanging from the ceiling,

You will probably need to build a proper cloud. Make it hard-backed, and angled.

did 95cm from side walls, 45 cm from front wall.

Try getting them closer to the front wall: you need them almost touching the front wall, except for the 10cm thick acoustic panels.

I moved them up, now is 122 but to the tweeter. From the manual of Adam S2.5A: "Tweeter should be positioned approximately at the height of your ears. "

It's better to have them a bit higher than that, to reduce reflections from the desk/console surface. The ART drivers on the Adam spekaers have pretty decent dispersion, and you'll be far enough away that you won't have problems from being too far off axis.

Can you me a hint what will be better on the rear wall of mineral wool or hangers? What worries me is big axial mode.

Both. I would put at least 10cm of wool directly on the wall, floor, and ceiling back there, then hangers at least 50cm wide, covering almost all the floor-to-ceiling distance (except for a couple of cm clearance, to allow the hangers to move freely). Angle the hangers a bit. Maybe 20° to 35°

Should I do first ceiling or rear wall?

Rear wall.

- Stuart -