Sound System Advice Needed.....

[eye4vision]

Hey Everyone,

 

I have a question / dilemma which I hope I can get some answers or at least some opinions.

 

Having already read a few other posts on the subject I'm pretty sure of the answers I will get, but here goes anyway....

 

I'm entertainment manager for a hotel, which also has a large capacity bar / club on the ground floor, when I started the sound system had already been installed.

 

The bar / club has a capacity of approx 800, we are full to capacity every weekend.

 

The sound system consists of various Bose speakers including 802 / 402 / 1 x MB24, 2 x smaller base units and a couple of LTs for mid highs….

 

There are also about 12 small bose speakers dotted around the edge of the room.

 

Every speaker is ceiling mounted.

 

The venue is sound proofed to 96DB… apparently!

 

There are various suspended ceilings in the venue and the way the speakers have been hung, half of the speakers are firing straight above the suspended ceiling (the suspended ceilings are fixed in place with metal hangers)

 

Right then…. Problem number 1…..

 

We have a terrible problem of noise traveling through the ceiling into the room above, which is a conference room and also to the two floors above that which are hotel rooms. From day one I have said that we should at least drop the large base units and mid tops to the floor, surely having them ceiling mounted is only making the problem worse. The solution at present is to turn the base down to -16db and the volume down so much that it doesn’t travel upwards, the problem now is that the sound in the bar / club sounds very quiet and tinny. Bose have insisted that bt dropping the speakers onto the floor will have no effect in reducing noise traveling upwards… I have said that I don’t think its is a volume issue but rather a vibration issue due the speakers being celing mounted (on hangers).

 

Now im not after nightclub volumes, but rather a good clean sound that people can enjoy and dabce to with ease. At the very least, I want to ensure a good sound on the dace floor area.

 

The owners have invested a considerable amount of time, effort and money in developing the hotel and bar, I fear ultimately the business will suffer due to an incorrect sound system being installed…..

 

I have to come up with either a solution with our current system or another idea on a way forward…

 

Im scratching my head not knowing which way to turn…

 

I probably haven’t covered everything here, so if you want to ask me any questions, please fire away……

 

In summary I guess I need to get opinions on the following:

 

Would dropping the speakers help reduce noise travelling upwards

Should they have been ceiling mounted in the first place

Should the local Av Company have spec'd a Bose system in the first place

 

Our venue is bar far the most popular in town at the moment but I fear if we cannot resolve these issues, it will be only a matter of time before the next new place opens and we will loose valuable customers….

 

 

 

Please help!!!

 

 

Moderation: Moved to the Sound Forum as that would seem a better place to get informed answers.

[johndenim]

Bose were not a bad choice at the time, ( I'd assume the install was done a few years ago) the physical size is good for this job, but there are far better systems out there now that would easily out perform the Bose coupled with subs.

 

I would suspect the reason for mounting the subs to the ceiling would purely be because they were out of the way, and dropping these to the floor would certainly reduce vibration.

 

If you had some decent sized subs you would not need many, but the problem of location arises once again.

I used to work for a company that repaired/installed similar systems but in night clubs, the restrictions here are a little less slack.

 

I would think that if you COULD have the subs on the floor, and the mid/hi's still ceiling mounted, and you crossed over the freqency so that around 200hz and above ONLY went to the ceiling mounted cabs, the vibration/bass travel would be reduced even further.

 

John Denim.

[Doug Siddons]

Your right its a vibration problem transmitting the noise up, you do need to find a way of isolating the cabs from the structure judicious use of foam pads ect will help, yes drop the subs, also would suggest you try reducing the number of speakers you are using. Install companies tend to over spec the amount of speakers you need ( I know I've done it!) Bose sysyems work well and last so no need to invest in new just a move round and rethink should help

[Sirch Sound]

To be honest if you really are serious about improving your system then its worth getting a pro to give you an on site visit, although some people on here are very experienced at install sound (I used to install nightclub systems, along with many others!) every single venue is different and theres only a limited amount you can suggest without actually seing the place. It shouldnt be too expensive to get a bit of advice, and I wouldnt be thinking about replacing the system, as it is perfectly adiquate for what your trying to do, it just needs some re-arrangement. The general way we used to do the pub/nightclub installs were subs under the benches or hidden in corners and then larger, full range tops (the bose 802's will be fine for quieter levels) either wall/cieling mounted or flown depending on size and the venue.

 

Without a doubt you need to be droping any subs to the floor, as long as you dont have too much trouble with any rooms on the same floor as this one. As for dropping the tops I really carnt see this doing too much, it will be the us that are causing most of your problems.My soluionwould be to flyth spaer, probaly clustr them to avoid the amount of flying points this way the ony vibratons that can yer up to the cieling will be that that travels through the wires of the flying kit and anything from the subs going up the walls, which will be minimal. Just to top it off, double insulate your cieling, that will give you a suprising amount of sound insulation, without rediculous prices of better soundproofing of the whole cieling.

 

However I said the best bet is to get someone in to asses your situation.

[cliveybaby]

All advice makes sense

 

I would also go down the route of using an adjustable Speaker

management unit after (if used) the bose system controller

 

with this you can remove some of the very low frequencies that

are most likely travelling through the ceiling

 

obviously you need to find a balance between unwanted bass and a

good live sound but you may me surprised as to the amount of

very low content you can remove before you ruin the

systems sound, due to the fact that some frequencies are 'felt' more than herd

 

ok some bass bins dont go down that low but the environment they are in and

the way they are placed can often increase these low bits and make

boomy sounds all over the place

 

DBX do some nice units

also Behringer ultraDrive is a very good budget tool for the job

 

Hope that helps

 

Cliveybaby

[Simon Lewis]

Irrespective of the loudspeaker system, you need to determine how much of the sound heard in conference room is via airborne noise transmission, and how much is structure borne.

 

This then determines whether you need to have acoustic isolation installed to reduce the level of sound upstairs, or whether you need to stop sound traveling through walls and floors by resilient mountings or by resiting the loudspeakers.

 

Tailoring the frequency response may help, but given the typical construction of most hotels, it may well be that a combination of moving the loudspeakers, floor mounting the bins on neoprene pads, but more importantly applying acoustic isolation to the ceiling will be necessary.

 

The technical research guys at Bose UK understand this stuff, and would probably echo the comments above. Their comment regarding sound traveling upwards indicates that they believe the primary problem to be one of airborne noise transmission.

 

It's not impossible to carry out remedial acoustic work yourself, but it's also quite easy to do it incorrectly, and see no improvement for your money. This is primarily an acoustic problem, so it would probably pay you to have an acoustician look at the building. He /she will be able to carry out standard tests to determine what is happening, and how best to treat it.

 

Simon

[veen]

If there's anyone who really knows acoustics it's bose. I would imagine the speakers(subs) are not rigidly mounted (ie. on chain or wire). If this is the case theres not alot you can do. Possibly move the subs to the floor, in a corner, which may make the bass seem fuller to the people in the bar without cranking things up. The general public are idiots and will put up with crap sound if the venue is popular as long as it isn't noticeably worse than your direct competition, hey even I will if there are enough attractive women, but then I do always carry earplugs with me just in case.

 

Just don't book any 'quiet' functions when you may expect a full bar. ££££