Is there a math for near-field monitor placement?

[johnbono]

Monitors: Dynaudio BM6A.
Room 15x20, center position on the 15' wall.
Monitors, angled about 30 degrees, are off my workstation and on stands about 5 1/2' apart with MoPads under them.

Questions:
How far from front wall is a safe distance for the monitors? I'm sitting about 4' from the front wall now, monitors about 2' away. Can I go back a couple of more feet?
5 1/2' Spread okay or should I go more?
30 degree angle okay?

[masteringhouse]

Originally Posted by johnbono

Monitors: Dynaudio BM6A.
Room 15x20, center position on the 15' wall.
Monitors, angled about 30 degrees, are off my workstation and on stands about 5 1/2' apart with MoPads under them.

Questions:
How far from front wall is a safe distance for the monitors? I'm sitting about 4' from the front wall now, monitors about 2' away. Can I go back a couple of more feet?
5 1/2' Spread okay or should I go more?
30 degree angle okay?

This may help:

http://www.stereo-speaker-buyers-gui...placement.html

[kylen]

Those are rear-ported I think ? Supposedly they shouldn't go too near a wall.

I think the variables involved in room vs speaker placement are such that the dimensions and calculations may just be guidelines and you still have to move 'm a bit to where the balance is the best.

At any rate this is my 3rd shot at setting my room up and that's kinda what I'm seeing - hearing, hehe.

I have front-ported speakers and they sound the most balanced right up against the wall (away from the corners though), toed-in a bit. But my room is simply studs and drywall on a 2nd floor so a lot of the low bass just passes thru I think so the bass standing waves aren't too bad...

[BrettB]

Paul White claims you can do some placement with the help of mirrors.

When you have to put your monitors too close to a wall, let someome hold a mirror behind it when you sit in your usual listening position.

Let your friend move around with the mirrior until you can see the back of your monitor in the mirror. Place an absorbing panel on that spot;

Just remember you want the least reflections possible from the wall behind your monitors.

[johnbono]

Great tips, thanks!

I realize I need to move things about somewhat. What I'm wondering is after looking at most studios that have soffit mount speakers and near-fields, it seems most have the nearfields quute a bit away from the wall. It's most likely due to the soffits being in the way.

I'm thinking of going back to about 6', (body position) which would put my monitors at around 2'-3' from the front wall.

[Ethan Winer]

John,

> How far from front wall is a safe distance for the monitors? <

There's no good answer. Moreover, no one place will give you a perfectly flat response. What happens as you move the speakers is the inevitable peaks and deep nulls change frequency. Some locations will indeed give a flatter response than others, but the difference is not huge. Certainly not as huge as you'd get from adding acoustic treatment and bass traps.

The best way to determine this for yourself is to measure the response of the room with the speakers at various locations. I use the ETF program from www.acoustisoft.com and it gives very accurate results - to a resolution of better than 1 Hz. You really do need such high resolution. Typical 1/3 octave tests are useless for assessing low frequency room response.

I'll also mention that there's a better way to work through this problem. Start with where you should sit while mixing, then determine the speaker locations based on that. In a typical rectangular room like yours, the best place for you to sit is 38% of the way back from the front wall. Then set up an equilateral triangle for the speakers. You can put masking tape on the floor that extends outward from the mix position. Then slide the speakers on stands or bar stools along the masking tape "lines" and measure, or just listen, with the speakers in each place.

--Ethan

[johnbono]

Gotta love this place! Thanks for the help! I'll be movng things about and go from there.