Skating rink bass build

[Tube Radio]

I have been djing at a rink for a few months.

They use several QSC K8 powered speakers and four Yorkville LS1208 subs.

I have adjusted the system as good as I possibly can, but the subs just aren't good enough.

Here's what I was thinking.

Four JBL 4520 cabinets with one in each corner for 100-40Hz.

Two larger bass horns one at each end of the rink for 40-20Hz.

I chose the 100Hz frequency as the QSC speakers have a switch for external subwoofer which inserts a high pass at 100Hz and that would simplify things as I wouldn't need an active crossover. Also the QSC speakers have a low frequency response of -6DB at 61Hz.

I plan on using Yamaha PX8 power amps with one for two 4520 cabinets and one for each bass horn due to those amps having built in DSP which will allow me to make the speakers sound their best.

Here's a couple pictures of the rink.





The subs are in only two corners which is part of the problem.

[grumpy]

Unfortunately, the photobucket linked photo also leads to pop up scam ads.

-_-

[Mr. Widget]

Why bass horns? They were really practical when a Crown DC300 was a big amp. Today's drivers handle gobs of power and Crown and others offer gobs of power at reasonable prices. I think you'll find, like everyone else has, that the modern crop of high powered bass reflex cabinets will give you superior performance.


Widget

[Lee in Montreal]

Why bass horns? They were really practical when a Crown DC300 was a big amp. Today's drivers handle gobs of power and Crown and others offer gobs of power at reasonable prices. I think you'll find, like everyone else has, that the modern crop of high powered bass reflex cabinets will give you superior performance.


Widget

Well. You'll need 3 or 4 times the power and twice the number of drivers if going to a bass reflex system.

In his previous post, I suggested TubeRadio to go to a modern bass horn such as Mog Mogale 18" Super Scoopers for more response below 60 Hz. The 4520 being technically quite outdated. Not to mention that the volume of that rink is huge. He will need more than 4 bass cabs for people to start feeling the bass, not just hearing it.

[Tube Radio]

Grumpy those are ads photobucket uses unfortunately.

Mr. Widget, sheer power isn't always the best way to go.

Ever seen a proper horn loaded woofer/subwoofer putting out insane levels of bass with the speaker cone barely moving?

Also efficiency is another reason as I can cover the area properly with less power than I could with bass reflex cabinets.

[Mr. Widget]

Mr. Widget, sheer power isn't always the best way to go.

Ever seen a proper horn loaded woofer/subwoofer putting out insane levels of bass with the speaker cone barely moving?

Also efficiency is another reason as I can cover the area properly with less power than I could with bass reflex cabinets.

Ok, let us know how it turns out.


Widget

[KCCT82]

Grumpy those are ads photobucket uses unfortunately.

Mr. Widget, sheer power isn't always the best way to go.

Ever seen a proper horn loaded woofer/subwoofer putting out insane levels of bass with the speaker cone barely moving?

Also efficiency is another reason as I can cover the area properly with less power than I could with bass reflex cabinets.

It's gonna cost you a lot more money, space, and time to set up proper bass horns. I'd go with widget's idea.

[Tube Radio]

In a way I can see why most modern pro audio subs only go to 40Hz. To build ones that go to 20Hz with any sort of efficiency will mean they are larger cabinets making them harder to carry around.


I had forgotten about the 4520 horns being short throw.

Thinking about it the bass did seem s little louder by the 4520s, but perhaps how they had them arranged pointing towards the middle of the rink made the effect of the bass lowering as one goes away from the horns less noticeable.

Looking at the super scooper plans it recommends a high pass of 30Hz as the driver unloads below that frequency.

http://speakerplans.com/index.php?id=18superscooper

This youtube video

https://www.youtube.com/watch?v=72huQJDXJnw

Used an Eminence Omega pro 18A driver for the super scooper.

Is that a good choice, is there a better driver or is there a currently manufactured JBL driver that is better?

Those may work and I could perhaps use two in each corner. I then may not have to replace the amps as they use two QSC RMX2450 amps I think (can check model number Friday to be sure) in bridged mono mode for the four Yorkville subs and have a built in selectable 30Hz HP filter.

The rink owner owns a construction company as well so could easily have the cabinets built.

[Lee in Montreal]

18" drivers have more potential than 15" ones. Definitely the way to go. Could be new PD1850, or maybe used JBL 2242

Start with two Superscooper per corner. And add more along the way. Remember that your rink is huuuuge. ;-)
Check if your amps or crossovers have 48db high pass filters.

[edgewound]

18" drivers have more potential than 15" ones. Definitely the way to go. Could be new PD1850, or maybe used JBL 2242

Start with two Superscooper per corner. And add more along the way. Remember that your rink is huuuuge. ;-)
Check if your amps or crossovers have 48db high pass filters.

21" drivers have even more potential than 18".

I don't understand the need to get all the way down to 20Hz when 30Hz is perfectly sufficient for a music playback system, unless you want to knock down the building and the people within it.

Bottom line...way too much bass is just obnoxious and actually can be abusive to patrons of the venue.

In my not so humble opinion, anyway .

[Lee in Montreal]

Looking at the super scooper plans it recommends a high pass of 30Hz as the driver unloads below that frequency.

http://speakerplans.com/index.php?id=18superscooper

This youtube video

https://www.youtube.com/watch?v=72huQJDXJnw

Used an Eminence Omega pro 18A driver for the super scooper.
Is that a good choice, is there a better driver or is there a currently manufactured JBL driver that is better?

Is the Eminence driver a good choice? I dunno, but it is cheap. Maybe worth testing. Qts might be a tad high for a horn loaded cab at 0.31
Also, looking at the response graph, you can see it starts falling from 100Hz.

I suggest you keep on looking or just get a set and test it. Can you borrow a variety of drivers and do tests and measurements?

BTW It is a good thing that the owner could build these cabs. Start with two, just to practice the building process and test them with various drivers.

@ Edgewound. Yes, you're correct. 21" might be cool too. Almost flat down to 30Hz... But the mop guy will be busy cleaning up just in front of the scoops... ;-)

[Tube Radio]

While getting help at the speakerplan forums I decided to look at some cinema subs

I found a JBL 4645C sub

http://www.jblpro.com/www/products/cinema-market/subwoofers/4645c

and figured I'd ask the JBL experts here if that would be a good choice.

It is small enough to where I might be able to disperse more of them around the rink than I could with any scoops, G sub or dual 18" subs.

[Tube Radio]

I looked at his designs for horns and subs and the only ones that go low enough are the 18" and 21" scoopers.

[cooky1257]

I looked at his designs for horns and subs and the only ones that go low enough are the 18" and 21" scoopers.

Indeed but the membership are mostly very experienced PA guys-ie they don't just use Roger's designs-lots of knowledge and advice available if you care to tap into it..

[Tube Radio]

It's more along of wanting to know what ways there are of doing the bass and a brief explanation of the pros and cons of each method.

In my opinion going with more modern high powered subs and the amps to drive them can be a rather expensive way to do it especially when it will take more than a few cabinets to achieve a frequency response of at least 40Hz in such a large space.

Whereas doing something with horns which are more efficient would mean less boxes which equates to less amplifier power needed and less overall money being spent.

Thing is I don't know how much money the rink wants to spend on the sound system so whatever I do has to work reasonably well and not be extremely expensive.