Subs missing on dance floor

Slaine01 · #1 10-29-2010, 06:50 PM

Playing a room where we are on a mezzanine and have a large (Casino) open space below us, we have a small dance area infront of us and I am running a Mackie P.A. with K.V. Audio powered subs.
My problem is that the subs are definately cranking but if you go to the dance floor in front of us the subs are fairly much non-existant.
I have checked all the relevant phase issues and that is not an issue, we play against a wall and I place the stacks about 1 metre from the wall, due to stage constrants, should I face the subs in another direction?
It does sound like a phase issue at first but the further away you go from the band the more the subs slowly dial in to the mix.
Dont have this issue with any other gigs we do so I'm figuring its the room.
Any ideas?

lord of sadowsk · #2 10-29-2010, 10:18 PM

yeah have had this issue as well. try facing the subs toward the corners of the room or towards a corner of a wall.

T-Bird · #3 10-29-2010, 10:27 PM

Hi.

Subs are a little bit hard to position to get the coverage uniform, but stacking 'em on a corner to form a "horn" will not only aid in that, but also reduce distortion and gain 3dB.

Regards
Sam

TimmyP · #4 10-30-2010, 12:34 AM

1 meter from the wall = a cancellation notch just above 85Hz, which is often where most of the kick drum energy lives, as well as a lot of bass energy.

Munjibunga · #5 10-30-2010, 01:40 AM

Are you separating the subs or clustering them? If the subs are apart, you will get serious comb filtering, resulting in big holes in the sound. Check it out.

TomB · #6 10-30-2010, 03:32 AM

Quote:

Originally Posted by TimmyP

1 meter from the wall = a cancellation notch just above 85Hz, which is often where most of the kick drum energy lives, as well as a lot of bass energy.

Are you referring to 1 meter from any wall no matter which way the speaker is oriented, or only to facing it towards a wall? Thanks.

Slaine01 · #7 10-30-2010, 07:58 AM

Quote:

Originally Posted by T-Bird

Hi.

Subs are a little bit hard to position to get the coverage uniform, but stacking 'em on a corner to form a "horn" will not only aid in that, but also reduce distortion and gain 3dB.

Regards
Sam

wow - awesome stuff guys.
The subs are about 3-4 metres apart.

Do you mean "stacking" as in - the two subs on top of each other?

Justin Tuskey · #8 10-30-2010, 08:23 AM

Quote:

Originally Posted by Slaine01

wow - awesome stuff guys.
The subs are about 3-4 metres apart.

Do you mean "stacking" as in - the two subs on top of each other?

Yes, stack those puppies and put them about 1 meter from a wall while against another wall in a corner. hopefully that makes sense. Ive had success with facing them TO the wall, but try different orientations. the above has worked for me, although I'm not sure if its the ideal location, I'm no expert.

T-Bird · #9 10-30-2010, 09:48 AM

Hi.

Quote:

Originally Posted by Slaine01

wow - awesome stuff guys.
The subs are about 3-4 metres apart.

Do you mean "stacking" as in - the two subs on top of each other?

Yes, as Justin said.
The principle has been used in several Hi-Fi subs over the years.

In the real world stages, most of the time the subs double as risers or stands for the mid+high cabs and also provide a visual and practical means to separate the stage from the rest of the space. While a reasonably good low freq coverage is possible with separate low freq stacks, an one point source is vastly superior.

Regards
Sam

fokof · #10 10-30-2010, 09:51 AM

+1 for center cluster (side to side ) if the stage is high enough or if it doesn't bother too much the dance floor

Slaine01 · #11 10-30-2010, 04:56 PM

They need to teach this is High Schools, forget algebra and tech drawing.. THIS is what matters in the real world!

Kromwarp · #12 10-30-2010, 05:04 PM

Call Jimmie Johns, they'll have subs there faster than anyone...

Justin Tuskey · #13 10-30-2010, 09:30 PM

Quote:

Originally Posted by Kromwarp

Call Jimmie Johns, they'll have subs there faster than anyone...

Ha! I only got this because we have one here in Savannah and a buddy of mine works there. classic.

Munjibunga · #14 11-01-2010, 12:17 AM

Quote:

Originally Posted by Slaine01

wow - awesome stuff guys.
The subs are about 3-4 metres apart.

Do you mean "stacking" as in - the two subs on top of each other?

Figures 41 and 42 show the patterns at 50 hz and 100 hz for subs separated 4 meters. Don't do it.

lowfreq33 · #15 11-01-2010, 12:36 AM

We put our subs as a cluster in front of the stage, and use them as a riser during guitar solos, etc. People always seem to dig it when 2 or 3 of us jump up there. Sometimes club owners are a little funny about it at first, but once they see the show they change their minds.

Downunderwonder · #16 11-01-2010, 10:47 AM

Radiating plane no more than 2 feet or more than 10 feet from the wall. So point them at the wall and get 6dB extra for free. Even more into a corner.

Don't separate subs unless by more than 56ft or you get the nasty cancellation.

lord of sadowsk · #17 11-02-2010, 07:28 AM

Hey slaine warcraft rocks

Slaine01 · #18 11-14-2010, 05:06 AM

Just finished our Casino gig with the 2 subs "stacked" on top of each other - problem solved!
Sound was killing it on the dance floor - had the place jumping all night.

and yes...Warcraft rocks... but Aion is waaaaay better...

greenboy · #19 11-16-2010, 07:36 AM

Also the reason why having dual bass rigs separated across the stage is usually a problem (besides - that gives guitarists yet another reason to turn up to hear themselves better since a bass rig is on their side of the stage).

Destructive cancellation of LF happens when the distances are greater than 1/2 wavelenght and less than 1 wavelength. Low frequency sources are best placed within 1/4 wavelength of each other, on the floor and not on a stage that's very high.

Zooberwerx · #20 01-29-2011, 06:53 AM

Quote:

Originally Posted by Munjibunga

Are you separating the subs or clustering them? If the subs are apart, you will get serious comb filtering, resulting in big holes in the sound. Check it out.

I showed this last night to a "semi-pro" soundguy who could not possibly fathom why my 18" subs were clustered (as illustrated). He had every lame reason in the world why it wouldn't be optimal, including "well, 90% of the bands run their subs left & right". I think he now has a grasp but brought up another interesting question: what is the proper configuration for mains & sub arrays when supporting large outdoor and / or amphitheater events? He mentioned multiple mambo sub enclosures, stacked mains, so forth and so on....the stuff you'd see at an outdoor concert. Are those sub enclosures centered or clustered in some fashion and, if so , how? My dealings have been limited to two mains on sticks and a pair of subs so I honestly don't have a clue.

Riis