Urgent: Sound 'Proofing' for a Music Festival

[avare]

There is so much going in your post and not that a non quoting response is appropriate.

The starw bale walls will reduce mid and high frecuency sound significantly (10-20 dB). They will do about nothing for low frequencies. Are the complaints mainly/exclusively about the low end? If so the most practical solution is to use cardioid low frequency stacks.

Well stacked,
Andre

[dannyc]

thanks for your quick reply!

when I was searching through google, it was your answers which popped up that really helped! I'm really glad you chose to respond.

Would you suggest that I do 2 rows of hay bales with no space inbetween? or 3 rows with 15-20cm inbetween each stack? May sound like a tedious question, but I trust what you have to say compared to the amount of crap that I've read.

Yeah the bass freq are the things that are getting me in a bit of strife. I think the subs may be cardiod, i'll check that tomorrow with the audio engineer and get back to you. I specifically remember him mentioning that they're quite directional. Again i'm not too sure.

Would rubber or any other materials on the first 1m of the height of the stage work if they're not cardioid? or would i better off just trying to rent those kind?

[avare]

Originally Posted by dannyc

thanks for your quick reply!

when i was searching through google, it was your answers that popped up and that really helped! I'm really glad you chose to respond.

Would you suggest that i do 2 rows of hay bales with no space inbetween? or 3 rows with 15-20cm inbetween each stack?

Yeah the bass freq are the things that are getting me in a bit of strife. I think the subs may be cardiod, i'll check that tomorrow with the audio engineer and get back to you. I specifically remember him mentioning that they're not uni-directional like alot of other subs.

Would rubber or any other materials on the first 1m of the height of the stage work?

I would suggest that you make a sketch, Sketchup works great is free and has online tutuorials. Barriers are effective in short range reduction. teh further away, hte less diffference they make.

Bass will lietrally "fly" over barriers less than a wavelenght high. The effective way to control bass is with directional stacks. I am not aware of any self contained directional subs except for Meyer. Directional arrays are made up of multiple subs in specific arrangements with specific timing and polaroty on the units.

Andre

[andrebrito]

You need to create barriers that have much more height regarding the speakers height and eventually have a slight slopped ceiling. Place the subs on the floor below the stage

Barriers are more effective located near the speakers

You need to use heavy materials for the barrier. Forget haybales

Get a SLM and if needed control the PA system volume. Sometimes reducing the emission 10-20 dB makes a huge difference and creates less deaf people on the audience !

[dannyc]

thanks for the tip, I'll have everything done in sketchup and all information about the bass very shortly! (it's 6am here).

[dannyc]

we will definitely have a SLM and measuring everything prior to the festival starting. was planning to put the subs below the stage. stay tuned for the sketches

[avare]

Originally Posted by dannyc

we will definitely have a SLM and measuring everything prior to the festival starting. was planning to put the subs below the stage. stay tuned for the sketches

Fantastic. Drawings are the language of equipment and venue description. I hope the drawings will include distance and direction to the neighbours.

Andre

[dannyc]

So the little green is the farm. The big square green at approx 500 m away is where an unmic'd drum kit will be mildly audible. the blue squares are uninhabited sheds. The pink is the direction the speakers were facing last year & green is where i'm thinking of facing them.

The subs we're using are Martin dual 18" front loaded - custom jobs. very similiar to jbl srx 218. According to my sound engineer they're not exactly cardioid, but they are close. Definitely not unidirectional. is having them vertical or horizontal better?

I'll have some more sketches of the stage and whatnot tomorrow. More or less I just want to figure out how to stack the haybales e.g. with 20cm space inbetween or not. e.g. wall with space = |_| |_|

wall without space = |_||_|

3 walls btw - Right and Left Sides and back - Front is obviously open

lots of questions i know, i really appreciate any well thought out advice as it's a huge issue for me.

[Rod Gervais]

By the way - is this flat land all around you - or does it roll off in any particular direction?

Rod

[andrebrito]

My opinion is the same.. place subs on the floor. Use highly directional flying PA. You need to create a barrier around the subs or around the stage as close as possible from the sound source.

Use heavy mass products. Place absorption on the barrier. Make them as high as possible.

If the barrier is not enough, reduce the sound power level of the PA.

[dannyc]

Originally Posted by Rod Gervais

By the way - is this flat land all around you - or does it roll off in any particular direction?

Rod

where the complaint person is there is a bit of a hill rise approx 15m high. That house is not a direct line of sight but we still got the complaints obviously re: bass. virtually all of the surrounding area is flat.

[dannyc]

Originally Posted by andrebrito

My opinion is the same.. place subs on the floor. Use highly directional flying PA. You need to create a barrier around the subs or around the stage as close as possible from the sound source.

Use heavy mass products. Place absorption on the barrier. Make them as high as possible.

If the barrier is not enough, reduce the sound power level of the PA.

subs standing vertical or horizontal (parallel to the floor)?

[avare]

Originally Posted by dannyc

So the little green is the farm. The big square green at approx 500 m away is where an unmic'd drum kit will be mildly audible. the blue squares are uninhabited sheds. The pink is the direction the speakers were facing last year & green is where i'm thinking of facing them.

The subs we're using are Martin dual 18" front loaded - custom jobs. very similiar to jbl srx 218. According to my sound engineer they're not exactly cardioid, but they are close. Definitely not unidirectional. is having them vertical or horizontal better?

I'll have some more sketches of the stage and whatnot tomorrow. More or less I just want to figure out how to stack the haybales e.g. with 20cm space inbetween or not. e.g. wall with space = |_| |_|

wall without space = |_||_|

3 walls btw - Right and Left Sides and back - Front is obviously open

lots of questions i know, i really appreciate any well thought out advice as it's a huge issue for me.

At those distances, barriers will have minimal effect. Changing the direction makes sense.

Directional subwoofer arrays are multiple woofers, not single units. See section 8 of Bass Arrays for one example. Note figs 24 and 26. This document is short enought to read in its entirity. It is obviously tied in with one company's product. A good section is pages 15-18 in A Practical Guide To Bass Arrays. Directional subwoofere arrays are not a simple to achieve with out research and appropriate electronics.

Andre

[AwwDeOhh]

Proposal B:

Offer the complaint neighbor "Backstage passes" and free food and drinks.

If they're at the concert, they won't complain!

[andrebrito]

subs on the floor, subs should face the opposite direction of the "complaint" house and have a barrier behind the subs as near as possible and on its sides as well