acoustic placement

[elliot]

bonjourno

wasnt sure where to ask this query but i think here is as good a place as any

basically due to my terrible mixes and bass light results im having to bite the bullet and invest in some acoustic treatment. i just wanted to know where the best place to put some bass trapes and tiles around my room.
as you can see its not the best of areas to use but im having to make do with wht ive got sorry for the long message

main area

to the right

over right shoulder (behind)

over left shoulder (behind)

to the left
[/img]

[HarBal]

Elliot,

Before going any further, have you exhausted all possibilities with regard to bass problems through speaker placement. If your bass problem is confined to largely one room mode you can often control it adequately by find the anti-node nearest your normal speaker position and positioning your speaker there. I generally find that most room bass issues can be reasonably well controlled simply through experimenting with speaker placement. Some speakers are easier to work with than others in this regard. Generally big speakers with multiple drivers are harder to decouple owing to the more spread out sound radiation origin.

Also, have you confirmed that you have a strong bass resonance problem in your acoustics by conducting a balloon burst room response test. If you don't know what I'm referring too please take a look at this post:

http://har-bal.com/ipw-web/bulletin/bb/ ... .php?t=244

I'd be curious to see what your room response (as measured above) looks like. You might find that the problem lies somewhere that you didn't expect.

If you find that you do need a bass trap installation you should try and preserve left-right symmetry otherwise you may end up with an unbalanced stereo image at the bottom end. That'll generally mean having to have two such devices. To maximise their effectiveness you should position the openning of the trap at a node for the mode you are trying to dampen down. Easiest way to find it is to put a loudspeaker in the corner of the room and play back a sin wave of the same frequency as your room resonance. Then walk around your room listening for a hot spot where the tone is loudest. That is a resonant node and that is the best place for a bass trap. Hopefully it isn't in an inconvenient location. Also, if you find that it is loud where your speakers normally sit then you've just explained your bass resonance problem. Speakers should be placed near the anti-node of LF room resonances so that they don't couple.

Hope this helps. I'm still tuning my room. It's close to what I'd like but I don't have the time to make the final adjustments on my panel absorbers yet.

Regards,


Paavo.

[dbmasters]

I steer away from formal treatments myself unless I need to. Near field monitors are designed to have as little of impact as possible made by the environment. Tohelp lessen things like bass resonance, you can try simple things like putting a tall bookshelf at an angle in the corners of of the room, or the corners that the speakers are facing anyway...when my studio moved in to my new house, into an unfinished basement, I built some of these http://www.homerecordingconnection.com/ ... tory&id=50 and built them pretty cheaply and they help control bouncing as well.

Acoustic treatments can cost a lot, but you can really do it cheap and easy if you are creative about it.

[HarBal]

"Acoustic treatments can cost a lot, but you can really do it cheap and easy if you are creative about it."

Well that depends. If you buy everything off the shelf then yes, it is expensive. If you build it yourself it isn't very expensive at all. In any case, if a room has frequency selective problems then off the shelf treatments aren't a solution because the treatment must be tune to the room and generally speaker, off the shelf treatments aren't that taylor made.

Dan, In short I'd generally agree with you, though near field monitoring does not reproduce the sense of space that a mid - far field monitoring situation in a room with good acoustics does. The apparent sound stage is that much wider and the sweet spot bigger, but you need to have a room that doesn't colour in the wrong way and has no plane reflections from the side walls at your listening position. Diffused reflections yes, plane reflections no. In my case, my plane refections were solved with a single diffuser unit on either side that stands about 1 m high and 20cm wide. It's actually only half a diffuser as I haven't finished making them and haven't had the time yet. When they're finished they will have cost me about $200US in materials. Given the difference in sound quality (which is enormous) it's a bargain. By the way, $200 may sound like a lot, but there is a lot of wood that goes into making a good broadband diffuser.

Anyway, Like I said, I generally agree with your sentiment. Only fix what you have to but if your room could benefit from acoustic treatment I'd certainly encourage anyone in need to do so. Any broadband treatment required can be bought off the shelf but if you need something frequency selective you really should consider making it yourself because it really needs to be tuned to the room.

Paavo.

[elliot]

i deal with synths only, no live stuff, surley for the mixing mastering stage i want to make this as dead as possible?

[HarBal]

Elliot,

It's a common misconception that rooms for monitoring music in should be dead as possible. They should not. A completely dead room is generally opressive to work in, lacks intimacy and sounds sterile. Having the right level of diffuse abience improves imaging and the size of the listening sweet spot IMHO. You'll probably find yourself over compensating on ambience effects and the like if your room is too dead.

In my experience, in a too dead room the sound sources will are more isolated by your brain, so it ends up like sounds comming from the loudspeakers rather than from somewhere in between (this is mid-far field monitoring).

Probably the closest you can get to a dead room is free field monitoring. Have you ever tried listening to loudspeakers outside? I've never found it very pleasing. It just lacks vitality and realism.

Even if you are near field monitoring it will still have an noticeable effect and, as I said before, the sweet spot in a dead room is pretty small, so you'll probably be the only one who can hear a reasonable stereo reproduction.

Finally, it is generally accepted that the only frequencies that are easily deadend are ones above about 400Hz or so. The up shot of that is the deaded you make it the more likely you are going to have a serious standing wave problem because your room resonances down in the bottom two octaves will hardly be deadend at all, whilst everything else will. Hence, your need for a bass trap.

On the basis of your comments it sounds as if you may have overdamped your listening environment.

Cheers,


Paavo.