Sound system for ballroom

[jyl]

Audio braintrust:

Ballroom, about 2500 sf, rectangular. High ceilings, wood floor, minimal draperies. Used for weddings and ballroom dances, bar mitzvahs, social gatherings, etc. For weddings typically half the room is tables and the other half for dancing. For dances the whole room is used.

I need to get a permanently installed sound system for the weddings. The wedding party renting the venue typically brings their music on a laptop or iPod, i.e. MP3 via a 3.5” audio jack, with Lightning or USB-C or micro-USB adapter dongle if needed. I guess it would be nice to accept a USB or HDMI input but it’s not necessary.

Max sound level desired is 85 dB. As in, we don’t want the system to be capable of going louder, no matter what the renter does or how much they turn up the volume on their laptop etc.

Do not want the system to be capable of producing heavy bass, no matter what the renter does.

The reason the desired SPL and bass are limited is because there are neighborhood noise restrictions we need to comply with, and I don’t want the manager getting in conflicts with some drunk guest who is trying to really crank up the sound.

Audiophile quality sound is not required. This is for wedding party music basically. Also background music.

Has to be idiot proof. The amp, controls, etc can be in a locked cabinet. At the start of the event, the manager unlocks the cabinet, turns the system on, then closes and locks the cabinet. The 3.5” cable would be accessible for the renter to use, but the renter would not be able to adjust the system’s volume or other controls.

Speakers will be mounted up high, out of the reach of renters. It would be nice to not have many speakers all over the place.

Budget is not large. Used gear fine. Plenty of change back from $1,000 would be nice.

What would you all suggest?

By the way, for simplicity I’m thinking of having the PA duties - for the speeches etc - handled by a separate PA system with a couple of wireless mics and some medium PA speakers. And if a group brings in a live band or DJ, they can bring in their own sound gear if this isn’t to their liking.

Here is the room (taped up for painting). This shows the end of the room that would typically be used for tables and dining.



This is the end of the room that is typically used for dances, and the stage where people would speak, live bands set up, etc. Sometimes ceremonies are on the stage.

[jyl]

There used to be four speakers, one hung in each corner, looked like regular “hifi” speakers like you’d have found in a living room in the 60’s (box cabinets, two way, feels like 8” woofer but the old style cloth grilles don’t detach. The speaker wire was the thin stuff you bought in a big spool from Radio Shack, stapled to the wall - I tore out hundreds of feet of it. There was a very old mixer board on the stage that the manager had to show people how to use, with lots of sliders and knobs for little kids and drunk people to screw with, and they ran the music and mics from it. The whole thing was a combination of complicated and . . . pieced together?

[jyl]

Come to think of it, sometimes people will bring a laptop and show videos on the projector and screen (not shown), so I guess that is another required input.

[billybek]

Too bad that Ian (Imcarther) doesn't stop in here anymore. He would be the go to guy for this question....

[id10t]

You will end up needing something to take your input and split the signal out to multiple speakers, perhaps play with some settings to minimize base, etc. Being able to take input from a laptop, hdmi, etc. and split it out as well. This is where I'd spend your money. Then worry about speakers, the actual cabling, etc. Be aware that a 50 or 100 foot long HDMI or VGA or DVI cable is gonna be a buck or two per foot.

[dad911]

I would think you are looking for a combo PA/DJ system. Inputs seem versatile enough for mp3s and projectors;

https://www.amazon.com/DJ-Speaker-Package/s?k=DJ+Speaker+Package

https://www.amazon.com/s?k=PRORECK+Club+4000&ref=nb_sb_noss_2

[908/930]

Idiot proof can not be done, can possibly be fool proof.

At some point you will probably want sound baffles in there, Dow corning 703 wrapped in material and hanging from walls and ceilings, will help with the echo from people talking.

I think to limit at exactly 85db will be tough, that really is not very loud, but you could add power resistors to the wire at the speaker terminal, will require trial end error. There are speakers like TOA F-2000 that are built for this type of use, possibly start looking for a used set of 4 or 6pcs.

[MysticLlama]

I put these in several restaurants and they worked well to spread the sound around so you didn't need to crank something up from one side or the other. Maybe out of the budget to get 6 or so + other stuff, but you might be able to find something else similar.

https://www.amazon.com/JBL-Compact-Full-Range-Hanging-Pendant/dp/B00519RS5U/ref=sr_1_3?crid=1SS1A1KLBQEZW&dchild=1&keywords=jbl+pendant+speaker&qid=1614472708&sprefix=jbl+pend%2Caps%2C248&sr=8-3

[jyl]

Originally Posted by MysticLlama

I put these in several restaurants and they worked well to spread the sound around so you didn't need to crank something up from one side or the other. Maybe out of the budget to get 6 or so + other stuff, but you might be able to find something else similar.

https://www.amazon.com/JBL-Compact-Full-Range-Hanging-Pendant/dp/B00519RS5U/ref=sr_1_3?crid=1SS1A1KLBQEZW&dchild=1&keywords=jbl+pendant+speaker&qid=1614472708&sprefix=jbl+pend%2Caps%2C248&sr=8-3

That is super interesting. Do you daisy chain them, so like right channel daisy chains down one side of the room and left channel down the other? Or did you drive from mixer with one speaker per channel so you could adjust level in each area?

[Gogar]

Mystic llama is closest to the answer. If you're trying to keep the overall noise down but the coverage even you need to think about it differently, almost like it's lighting.

Imagine if you had a huge spotlight in each corner and tried to light the room with them. Speakers accomplish the task the same way. People close to the speakers are miserable and people in the middle of the room are also miserable.

A larger amount of smaller speakers will maintain the coverage but keep the overall "energy expended in the room" low. It will sound better and it won't escape the room as easily. Nothing is going to sound amazing in that room but that's not what you're looking for anyway.

The pendants from above are "70 volt" speakers which do not require individual AC power but will need an amp somewhere in the room. Yes you daisy chain them. They do have a benefit in that you can have lots of them in the room, at quieter volumes. It is unlikely that they would be able to handle "wedding dancing" volume, however.

If you wanted to be clever and super elegant you could find a way to hang one (or a few) in each lighting fixture!

You could also mount a traditional trapezoidal speaker along the top of each wall angled down towards the floor 1/3 of the way into the room. You could buy "powered" speakers which will require AC to every speaker and also the signal wire. If you had 6 or 8 of them spread throughout the room they would do great and actually be quieter than a speaker in each corner destroying itself trying to cover the whole space. You could mount them horizontally along the top edge of the long wall so the coverage angle of each speaker is utilized most efficiently in the room and not throwing sound up into the ceiling or unnecessarily into the floor. Another alternative could be mounting them to the beams and you could paint them to match the beam color.

Last option is you could buy conventional unpowered speakers and wire them to a power amp somewhere in the room. Which is similar to what you just removed. Also a fine choice and very similar to the "70-volt" speakers but sounds better. Downside is slightly higher cost. It's also easy but you would need to be careful with the wiring as there are rules to "how many" speakers can be wired together to one amplifier. It's not difficult you just have to do some super easy math.

Oh yeah and increase your budget by a factor of 10, generally speaking.

[masraum]

One problem that I see with the sound level, and maybe I'm wrong, but if you're expecting the 3.5mm output jack on a laptop, phone, ipod, often the output on that jack is variable. If they turn up the volume on the device, then that jack puts out a stronger signal which yields more volume. Maybe there's some device that you could have that would limit the input signal to a certain level, hopefully so.

I would think that the best bet would be to make sure that the speakers and gear aren't that good, so the volume can't go too high and/or they get horrible sound if they try to go too high.

Good luck, it'll be interesting to see how your ball room renovation goes.

[MysticLlama]

Those pendants are actually switchable, 8ohm (normal) or 70/100v (commercial, usually for things like lots of speakers on one line that have individual volume at the speaker), that was one of the bonuses, could work with whatever may have happened to be around if not starting from scratch.

When using them, I suppose you could do left vs right, we rarely did that except in a couple particular rooms and usually just used a mono source to them to provide even coverage. They are reasonably efficient and don't need a ton of power.

They also sound like they have some bass when you're right under them, but really don't have the power to make that travel far.

Like Gogar explained, you can get a lot more even volume in the room and lose less of it out of the venue with a setup like this vs the corners or ends.

An amp like this could drive 4 of those speakers wired in parallel (daisy chained two on each channel), which drops the load to 4 ohms and gets you 60w each.

https://www.amazon.com/Audio-Source-AMP100VS-Channel-Amplifier/dp/B00ZSEFU94/ref=sr_1_1?dchild=1&keywords=audiosource+4+channel&qid=1614494177&sr=8-1

I think that room probably needs closer to 8 speakers, but given the budget that gets tricky. With a setup like this you could get an amp + 4 speakers, and then just add another 2-4 speakers later if it's not enough.

If PA is separate and this isn't for the DJ/Dance portion of an event, might even get away with 4 if you get them up high enough for coverage area.

[dewolf]

Live band...

I have a very good friend here in Australia that is a TV Audio Sound Manager. Sets up stages etc for TV live performances. These can be in the studio, theatre park etc.
I can put him in touch if you'd like.

[john70t]

The stage is facing and functional to only half the room, so you might want to think of going from there.
Divide the areas.

Usually people expect band sound to be originating from directly in front of them.
More watts for that half the room, but a few more speakers in back for those sitting and eating far away.
Not everyone want to sit and quietly eat right in front of a subwoofer.

Muti-use-capability is better for rent-ability.

That room will create weird echos and bad sound effects at high volume.
There are two open roof lines for sound travel.
Some sound deadening panels might help at the ends.
The speakers need to be at an angle.

I don't know how many separate and tune-able channels that would require...6 or 8 perhaps.

[jyl]

Wow, thank you all for the help. This is what I’m taking away:

Line source: I hadn’t thought about how the line input from one device might be a little different from the line input from another device. I think that is okay, we can make sure the manager (but not the renter) can access the mixer or amp and adjust the volume as needed.

Different zones: For weddings, I think we’d want dance-appropriate volume in the half of the room where the stage is, and conversation-appropriate volume in the other half. For ballroom dances, we’d want dance-appropriate-volume throughout. So, two zones and the manager should be able to control the volume separately.

Speaker type: Pendant speakers would look cool, handle the conversation-appropriate volume, might have a harder time handling the dance-appropriate volume (?), might be too expensive. PA type speakers would have to be placed thoughtfully (not just one in each corner), could handle both volume levels, might be visually obtrusive.

Budget: Our budget is indeed very limited. I’ll probably end up buying the gear and donating it (this is the venue that was donated to our neighborhood association). But our ambitions are also limited, given our constraints of max 85 dB and not too much bass. We don’t have much time to get something usable thrown together (building needs to be ready to host events in 1-2 months) but we can always improve it next year when the place is making money.

dewolf, I’d love to be in touch with your friend. I’ll PM you my contact info.

[id10t]

Originally Posted by jyl

Wow, thank you all for the help. This is what I’m taking away:

Line source: I hadn’t thought about how the line input from one device might be a little different from the line input from another device. I think that is okay, we can make sure the manager (but not the renter) can access the mixer or amp and adjust the volume as needed.

Consider two mixers inline - one available to renter, with full control, that feeds an "inaccessible" one that will not let any of the volume settings/bass/etc. go over whatever limits you have it set at. That second locked-away one is what is feeding the speakers, etc.

[Gogar]

If you're renting the room for weddings and dances I suggest you (don't even try) to supply equipment for a band or a dj working the party. Many bands and EVERY dj hired to work at an event can supply their own sound system and would probably suggest doing so.

If it's at all possible remove yourself from that equation altogether and simply rent the room and require the renting party to find their own solution, which is very common. You can find a small sound company to start a relationship with and you could supply the referral when someone rents the room. At that point your cost is $0 and all that's required of you is being the "noise cop" during the event. Also very common. (PS that shape of room full of people talking with NO music playing whatsoever will be darn near 85dB on its own.)

In the meantime if you would like a very basic "restaurant-cocktail style" solution you could buy 4 sets of mystic llamas JBL speakers and an appropriate amp and basic mixer. Hang one pendant in each lighting fixture and it would be discreet and perfect. You'd probably be about $2k all in.

There's also plenty of speaker shapes that could be mounted on the beams or on the 45 degree beam supports that would look great and supply similar (maybe even better) coverage.

If during an event you want to let the client/band/dj/ tap into your little speakers to supply a little better coverage to the back of the room, that's easy as well. With (as mentioned) a locked cover on the master level to keep things from getting abused. Also very common.

[Gogar]

Like this. If you hang one of these on each side of every 45 degree beam support (and buy a few more ala carte) you would have pretty reasonable coverage and consistent cocktail-party level volume. This amp even has 4 inputs so you wouldn't even need to buy a separate mixer.

https://www.ebay.com/itm/JBL-VMA1120-Commercial-70v-Bluetooth-Amplifier-10-Wall-Speakers-For-Restaurant-/303878838482?_trksid=p2349624.m46890.l49292

The pendants are sexier but perhaps more expensive and would only provide about a 120 degree cone of coverage underneath.

You could also do a combination of these shapes -and pendants and adjust the "tap"'on each speaker to adjust the relative volume of the different locations/shapes of each speaker.


The (perhaps only) benefit of a 70v system is that it's easy to add more speakers if you like, or to swap out the power amp for a little more oomph down the road. It's still relatively easy with conventional speakers, but takes slightly more care with wiring and is more expensive.

[Gogar]

If that idea is attractive then I would suggest you buy the higher power amp:

https://www.bhphotovideo.com/c/product/1322845-REG/jbl_vma1240_vma_1240_5_input.html

And you could stick with something similar to the Rockville speakers in that eBay combo:

https://www.rockvilleaudio.com/wet-5b/

Add ala carte the number you need, and set the tap on the back of each speaker so the TOTAL wattage is about 80% of the 240 watt amplifier. If you buy 10 speakers at $58 and set the tap to 20W each and the amp for $450 you're near your budget not including wiring. You could even add a 1-gang wall volume knob/input selector that you could switch between an announcement mic and music:

https://www.bhphotovideo.com/c/product/881073-REG/jbl_csr_3sv_wht_csr_3sv_wall_mounted_remote_contro l.html


It's ABSOLUTELY not "dance" or "band" loud. Not even close. It'll probably hit 85 though.

[jyl]

Originally Posted by Gogar

If that idea is attractive then I would suggest you buy the higher power amp:

https://www.bhphotovideo.com/c/product/1322845-REG/jbl_vma1240_vma_1240_5_input.html

And you could stick with something similar to the Rockville speakers in that eBay combo:

https://www.rockvilleaudio.com/wet-5b/

Add ala carte the number you need, and set the tap on the back of each speaker so the TOTAL wattage is about 80% of the 240 watt amplifier. If you buy 10 speakers at $58 and set the tap to 20W each and the amp for $450 you're near your budget not including wiring. You could even add a 1-gang wall volume knob/input selector that you could switch between an announcement mic and music:

https://www.bhphotovideo.com/c/product/881073-REG/jbl_csr_3sv_wht_csr_3sv_wall_mounted_remote_contro l.html


It's ABSOLUTELY not "dance" or "band" loud. Not even close. It'll probably hit 85 though.

Is there a way to calculate the expected loudness? Suppose 10 x speakers at 20 w tap? I didn’t see any SPL spec.