Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Ivan Beaver]

Interesting thread. Just curious: would the type of sub (bent horn, straight horn, vented box, etc) make a difference in placement options?

For the most part (there are a few exceptions), all types of subs are omni-so it won't matter.

The horns used in typical bass horns are for gain-not pattern control.

They don't work for pattern control because the mouth is to small.

Now putting subs in corners or against walls can help in the SPL-because the radiating area is reduced by the wall/boundary.

Generally horns can benefit more from wall loading, because it can help extend the horn walls.  Which can help extend the low freq response.

[Steve Garris]

I have a couple of venues where I often supply sound. I've tried different sub setups and the basic L/R placement seems to be best to my ears. Center clustered didn't really work....at those locations.

This has been my experience too, but Luke's explanation above is so well written that I saved it to a word document.

[Jamin Lynch]

This has been my experience too, but Luke's explanation above is so well written that I saved it to a word document.

Might be some good generic guidelines, but they don't always apply for every situation.

[Ivan Beaver]

Might be some good generic guidelines, but they don't always apply for every situation.

Exactly.  Different situations need different approaches.

Also "directional arrays -endfire-cardoid etc" don't automatically work.

If they are close to a wall/boundary all sorts of other "odd" things can start to happen that you did not plan on.

Also there are no models (that I am aware of) that can model subs in 3D with walls/reflections/boundaries.

So what might "look good" in a 2 D model or a 3D without reflections, could be VERY different in a real room.

It is good to understand the basic principals and follow them.

Sometimes if you try to get "to fancy" all you do is screw it up.  Or it might work well in one place-but completely wrong in another.

It is the TOTAL sound field that you have to be interested in-not just all the freq-but also all the directions.

[Jerome Malsack]

So Ivan I have attached a photo of my music room and used the Room EQ Wizard to create this picture of the problems with the Sub in my music room.  This is the Acoustic problems with the room
at 46 hz and 90 hz  Room modes ringing on long 150 to 200 ms. 

[Jerome Malsack]

I am adding the picture to provide an sample to visualize and explain. 

The room acoustics are based on normal room  8 ft ceiling basement with two walls poured concrete, and floor concrete.  Ceiling is 2 x 6 joists with 1/2 drywall and insulated other two walls are 2x4 studs with 1/2 drywalland insulated.    12 x 24  room.  Not on the best of sizes because not in the correct ratios and 8 x 12 x 24 is multiples that cause the room modes to be bad. 
 

[Steve Garris]

A few important quotes from Luke's post:

How the stage is made and the venue itself can impact the sub array design. It will always be a compromise and there is not necessarily one best way.

Your ability to get a good result is more than likely based upon your knowledge of sound in general. The physics play a large part in making it easier, but crap in is still crap out. Since most systems at that level are set up relatively the same, you only have to be better than the next guy at sound, more so than physics. Better gear and deployment make the job easier and acquires better results, but it doesn't say anything for your ability to produce good sound. I say that a monkey could twist the knobs and make things sound great, but can he set it up from scratch and design a system that will get him their on his own? If you start with a great system that is deployed well, the other part is a lot easier. If you can make 7 out of 10 people happy, your doing pretty good. Sound is subjective and what one thinks is amazing another thinks sounds like crap. The system as a whole does not have to be perfect, but having each part of it do what you intend for it to, is a great step forward. That is where the physics and the goals come in. Chances are good that a system that is 80% perfect ( in terms of measurable performance ) is better than not knowing a performance standard at all?

[Jamin Lynch]

Some of these room modeling programs I've used made me want to quit sound. No matter what I did it "appeared" it was going to be bad. I couldn't win. Then I would add in for walls and ceilings...holy crap, I give up.

Now I look the room over and use my best judgment from past experiences on how to deploy the system.  If it doesn't work as expected, I will try something different next time to see if it improves the sound quality. Usually my first impression is correct or really close.

Then there are those places where you have no choice where you can located your subs. Just do the best you can.

[Jamin Lynch]

Some of these room modeling programs I've used made me want to quit sound. No matter what I did it "appeared" it was going to be bad. I couldn't win. Then I would add in for walls and ceilings...holy crap, I give up.

Now I look the room over and use my best judgment from past experiences on how to deploy the system.  If it doesn't work as expected, I will try something different next time to see if it improves the sound quality. Usually my first impression is correct or really close.

Then there are those places where you have no choice where you can located your subs. Just do the best you can.

Just to add:

In the proper hands and with known values, a good room modeling program can be a valuable tool. Such as an install with CAD drawings. You still need to use good judgment though and not rely strictly on the program.

Most of the time, especially here in the Lab lounge level, we have no data prior to the gig to be able to perform a good reliable molding of the room. We are loading into a bar, club, or hall with no opportunity to run a room model. So you just have to use good judgment and experience.

More power to you if you do have the opportunity to model the room.

[Luke Geis]

Room modeling is a tough one....... The practical application has its merits, but you really have to know the room. Curtains, type of wall material, flooring ( solid or joisted, concrete or wood ) exact layout, H/D/W all factor into it. Many programs can get you a good idea, but it will not be exact. It is more to fish out major problems. Where you place the subs may not be a choice you get, so you will have to model different arrays that fit in that space to see how they will work. This is where the software can be helpful. It will not necessarily map the room for you, but you can get an idea as to what will work best.

The learning curve with many of the software's is high. You really have to understand how it works and it really helps if you can actually use the gear that it is designed to model. That is the tie in. When you use the gear that is modeled you can base your real world results against the model. This allows you to judge how accurate your model is against how it will perform for real. Over time you will be able to design a model and know that you need to tweak this way or that to acquire the actual result your looking for. A software type like Ray-End is a little more open source and will be less accurate, but is a great tool for getting an idea of what to expect. At the very least you can run with the model and adjust from there to suit your needs. It won't be perfect, but should get you most of the way there.

[ProSoundWeb Community]