[Takeiteasy]

Hi guys,

We are supplying the sound for a small number of outdoor events this year (MAX3000) and are thinking about building / designing a cardioid sub array of some sort.

I've read on another forum that just by blocking a large number of subs together in one place you get the same results or at least this is what they seem to be saying......

One member said ''That's why I laugh when people spend ages making a cardioid sub array... just use the right enclosures '' In this case they are taking about large hornloaded single 18" sub

If this is true why do people bother building cardioid sub arrays ? Seems odd that people like d&b would go to all that effort to design cardioid subs when you can block them together and get the same results.

[kerry davies]

Have you seen this one; BR


Just to add, having had a demo on an industrial estate which virtually shook the Brohome cladding off a warehouse while we stood next to the subs holding a normal conversation I can see the advantages.

This post has been edited by kerry davies: 17 February 2012 - 11:23 PM

[Takeiteasy]

woow thats quite a lot to get my head around... off I go

[Matt Riley]

The EV paper on Cardiod Sub Arrays is also a very valuable primer in addition to the thread referenced above.

It's quite complicated, but when they talk about a long line of subs, then they are right in saying that these provide highly effective pattern control.

Unfortunately the kind of dispersion offered, especially at the higher frequencies (a 24 foot array (say 6 218 subs) would produce roughly a 60 degree dispersion pattern at 60hz and a lot narrower at 100hz). Any of the approved approaches outlined in the paper above will produce some great results compared to your bog standard left-right stack, and having had a go a few years ago, I would thoroughly recommend looking at implementing something like a curved or a beamformed array as it will likely have a really significant improvement in consistency of bass coverage, and may also provide other benefits such as less sub energy on stage and reduced volume readings off site for outdoor gigs.

D&B and Nexo et al use gradient arrays, predominantly to deliver benefits like those described above using a far smaller number of speakers by driving them at different amplitudes and phases.

[Takeiteasy]

So am I right in thinking you get reduced SPL behind the stage if you block 12+ cabinets together at the front of the stage but the consistency out front in the crowd can suffer ?

[Matt Riley]

Takeiteasy, on 17 February 2012 - 11:50 PM, said:

So am I right in thinking you get reduced SPL behind the stage if you block 12+ cabinets together at the front of the stage but the consistency out front in the crowd can suffer ?

Nope sadly not - if you were to just bash them in a line, then my understanding is you get the same sort of narrowing backwards as you do forwards.

This post has been edited by Matt Riley: 17 February 2012 - 11:56 PM

[Takeiteasy]

Ok so learning EVERYTHING about how to build a CSA is the way forward if we want the best sound.... I've got a fair understanding as to how to build a sub array after spending weeks on the ProSoundWeb site asking around and playing with MAPP but after reading ''That's why I laugh when people spend ages making a cardioid sub array... just use the right enclosures'' I started to question why I was taking all this time to learn about sub arrays.

Lots to learn .... not much time :?

[RichM]

Takeiteasy, on 17 February 2012 - 10:27 PM, said:

Hi guys,

We are supplying the sound for a small number of outdoor events this year (MAX3000) and are thinking about building / designing a cardioid sub array of some sort.

It's well worth doing. If done properly you'll have a much easier time keeping the noise police happy.

I've been stood behind a Meyer array at a large festival where you almost couldn't tell if it was on or not, it was uncanny.

[Simon Lewis]

RichM, on 18 February 2012 - 10:18 AM, said:

It's well worth doing. If done properly you'll have a much easier time keeping the noise police happy.

In fact, where noise is likely to have an environmental impact, it is likely that techniques such as beam steering and cardioid arrays will be expected as part of the mitigation measures.

[techywhizz]

This is a great question, with any people with similar questions.

We've got Steve Jones from D&B coming to give an evening seminar titled " cardioid sub arrays explained.." this is an evening looking at methods to achieve even sub bass coverage whist minimising unwanted energy elsewhere ..

Wednesday 16th May at SFL

For more details check out Linky

This post has been edited by techywhizz: 18 February 2012 - 12:38 PM

[Takeiteasy]

You can can on me being there Matt

(**Matt, could you email me at info@truesoundhire.co.uk the cost of the complete flying system we came down to test out for the d&b, sorry I haven't been in touch just been busy that's all)

[stu00c]

If you are interested in creating cardioid or steered bass arrays, have a look at this clever subwoofer steering calculator from Community. The quick start option references Community products but it can be used as a generic tool for designing arrays with other brands products too. Community S4 - Subwoofer Steering Simulation Software

[splodge360]

Quote from Roger Mogale at Void:

"While the directional arrangement on the previous page can provide 15 to 20dB of front to back rejection the overall output SPL compared tothe same amount of enclosures all facing forwards in phase will alwaysbe less. The price to pay for greater front to back rejection is adecrease in overall SPL, especially at lower frequencies".

Ive also been experiementing in using some unwanted spare subs pointing backwards, out of phase, and delayed, but because there not the same spec and power handling as front PA stack, not not working out beneficialy yet. You can probably hear me test out across the field between us Tim!

This post has been edited by splodge360: 25 February 2012 - 03:07 PM

[chelgrian]

splodge360, on 25 February 2012 - 03:06 PM, said:

Quote from Roger Mogale at Void:

"While the directional arrangement on the previous page can provide 15 to 20dB of front to back rejection the overall output SPL compared tothe same amount of enclosures all facing forwards in phase will alwaysbe less. The price to pay for greater front to back rejection is adecrease in overall SPL, especially at lower frequencies".

Ive also been experiementing in using some unwanted spare subs pointing backwards, out of phase, and delayed, but because there not the same spec and power handling as front PA stack, not not working out beneficialy yet. You can probably hear me test out across the field between us Tim!

It's worth reading Roger Mogale's guide to bass arrays. It's got a large run down of different setups and pictures of the patterns you get out of them.

http://www.voidaudio...s%2520guide.pdf

Unfortunately he's not got around to writing part II yet.

[Peter F]

There's a mistake in the link given above. You can get to the pdf by following the download link to Void Bass Guide on their website.

Link to Void website

Cheers,

Peter