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[Ivan Beaver]

Exactly -- 800 lbs is way too much.

Have you ever weighed a large cart of full size line arrays? 

If you have the same physical size of Meyer leo you have almost 900 lbs

And that is just the cabinet weight-not flyware etc.

But again it all depends on the types of jobs that you are doing.

If you are not doing large jobs-then yes the weight is a bit much.

You also have to look at what it would take to replace it-not just the individual weight.

Have you every moved around large cable trunks?  Like feeder cable or 56 pr snake cable?  800 lbs is light.

What about staging sections?  Those carts are also very heavy.

It depends on your frame of reference.

BTW we move the J1 around all the time with no issues.  No big deal-until you hit steps-but then steps would stop any large cabinet.

And you can put it on a "stick"with no problem.   It just has to be a large stick-and yes it has been done

[Cailen Waddell]

Have you ever weighed a large cart of full size line arrays? 

If you have the same physical size of Meyer leo you have almost 900 lbs

And that is just the cabinet weight-not flyware etc.

But again it all depends on the types of jobs that you are doing.

If you are not doing large jobs-then yes the weight is a bit much.

You also have to look at what it would take to replace it-not just the individual weight.

Have you every moved around large cable trunks?  Like feeder cable or 56 pr snake cable?  800 lbs is light.

What about staging sections?  Those carts are also very heavy.

It depends on your frame of reference.

BTW we move the J1 around all the time with no issues.  No big deal-until you hit steps-but then steps would stop any large cabinet.

And you can put it on a "stick"with no problem.   It just has to be a large stick-and yes it has been done

If we could roll out one speaker to each side of the stage at our amphitheater, hook a single motor to each box, connect the cable, and hit up...  Times all the events a rig goes in... Huge labor savings alone.

Who cares what it weighs.  That's what wheels are for.  If 4 guys can 4 corner it and push it then I am good. 

[Peter Morris]

If we could roll out one speaker to each side of the stage at our amphitheater, hook a single motor to each box, connect the cable, and hit up...  Times all the events a rig goes in... Huge labor savings alone.

Who cares what it weighs.  That's what wheels are for.  If 4 guys can 4 corner it and push it then I am good.

If you always have a loading dock, ramps, chain motors etc. then there is no problem, but I can guarantee that will not always be the case.
 
What if you can’t drive you truck up to the stage and you have to push the box over wet grass?

What do you do if you have to ground stack a 800 lb speaker box? Four guys lifting an 800 lb speaker box would breach my OHS regulations.  To be compliant I would need 10 – 14 guys and a matching number of handles on the box!

At my Sunday casual labour rate it would cost me $2640 ($55 per hour - minimum call 4 hours) for enough people to lift those boxes.

Then there is coverage, what if the +0 -40 degree vertical pattern of the J1 is not suitable. Is there an up-fill or down-fill box to match?
 
How do I rig it, there does not seem to be any information about the fly-ware, rigging equipment and safety factors etc. that I can find on the Danley site. (Please correct me if I’m wrong)

I looked at the gigs I have done recently - I’m only a small operator,  but they range from about 200 person corporate event to 8000 / 10000 seat arenas.  Then I looked at what boxes I would need from Danley’s range of products.

I would need lots of different Danley boxes, which starts to complicate the logistics, and cost advantages Ivan is talking about starts to disappear.

Provided the SPL requirements for the arena are not extreme I can do all of these with things like d&b’s V Series, Flex Array, JBL VTX20 etc.  If I need something bigger then I can use J series with V out fill, Flash Line with Flex and VTX25’s & VTX20’s.

Without getting into the line array verses the point source debate, to me this looks logistically much better than the solution Danley is offering so far.
 
Soooo back to my earlier statement … looking forward to seeing what Danley has come up with 

[Cailen Waddell]

If you always have a loading dock, ramps, chain motors etc. then there is no problem, but I can guarantee that will not always be the case.
 
What if you can’t drive you truck up to the stage and you have to push the box over wet grass?

What do you do if you have to ground stack a 800 lb speaker box? Four guys lifting an 800 lb speaker box would breach my OHS regulations.  To be compliant I would need 10 – 14 guys and a matching number of handles on the box!

At my Sunday casual labour rate it would cost me $2640 ($55 per hour - minimum call 4 hours) for enough people to lift those boxes.

Then there is coverage, what if the +0 -40 degree vertical pattern of the J1 is not suitable. Is there an up-fill or down-fill box to match?
 
How do I rig it, there does not seem to be any information about the fly-ware, rigging equipment and safety factors etc. that I can find on the Danley site. (Please correct me if I’m wrong)

I looked at the gigs I have done recently - I’m only a small operator,  but they range from about 200 person corporate event to 8000 / 10000 seat arenas.  Then I looked at what boxes I would need from Danley’s range of products.

I would need lots of different Danley boxes, which starts to complicate the logistics, and cost advantages Ivan is talking about starts to disappear.

Provided the SPL requirements for the arena are not extreme I can do all of these with things like d&b’s V Series, Flex Array, JBL VTX20 etc.  If I need something bigger then I can use J series with V out fill, Flash Line with Flex and VTX25’s & VTX20’s.

Without getting into the line array verses the point source debate, to me this looks logistically much better than the solution Danley is offering so far.
 
Soooo back to my earlier statement … looking forward to seeing what Danley has come up with 

Tim +1. For touring I agree.  I should of been clearer, our local amphitheater does about 50% self production.... Load in our own gear for every show.... 

I also look forward to what Danley is going to offer

[Tom Danley]

Isn't a "true point source" just as mythical as a "true line array" ?

Hi Guys
David asks “Isn't a "true point source" just as mythical as a "true line array" ?”

Well no. To use an optical analogy, a line source is a Cylindrical lens; a system which has a focal point in one plane that is infinitely far behind the source. With the wavelengths of light being so small it is easy to make a lens that is large enough for this to be a reality, spanning from ultra violet to infra red (a bandwidth wider than the visible spectrum).   A point source is like a convex lens, it has a focal point at a finite distance behind the lens.

Acoustically, one finds the line source must be infinitely long (about 40-50 wavelengths) to be an acoustic line source with the cylindrical dispersion which gives half the fall off that the inverse square law delivers.  For a point source, which expands in both planes, the size requirement is that it must be very small as to not have source directivity. The most common image people think for point source radiation is of a rock hitting a pool of water.  Just like the line source, there is a size relationship involved and by size I mean relative to the wavelength being produced and as opposed to “infinite” as in 40-50 wavelengths or more, the limit for a freely radiating point source is that the source must be less than about ¼ wavelength in size or less.

What we make are point sources which radiate a segment of spherical radiation and not the entire sphere.  They use multiple drivers too but they are always less than ¼ wavelength apart where they interact with each other and so like close coupled subwoofers, the sources all combine coherently into a single new radiation like that of a single driver.

The reason for a segment of a sphere is that IF one can produce a single lobe who’s shape is constant over a wide frequency band (constant directivity) , then as one moves off axis only the SPL falls but the spectrum stays the same.  This allows one to use the old time trick where one adjusts the mounting height and aiming angle so that the audience up close is on the underside of the lobe so that the SPL can be very nearly constant everywhere and the sound is essentially the same everywhere. 
In the system Clair bros  just installed at Penn state, they measured a variation of only + - 2dB throughout the stadium.

The issue with line arrays is that they do produce directivity but the sources all radiate independently as well.  The combination of a constantly changing acoustical size and the individual radiations results in a source that radiates a LOT of energy outside the lobe as well. While this is not often shown, what line arrays do here is shown in figure 8 here based on the measured results.  Note how much the radiation above and below the array changes with frequency.

http://www.danleysoundlabs.com/danley/wp-content/uploads/2012/01/line-array-paper.pdf

It is the self interference or interference pattern the arrays produce that makes them so sensitive to wind and limits their “usable throw” / working distance as well as makes them sound different if one moves their location.

Robert wrote “The problem is, when the speaker has a vertical dispersion of only 15 degrees, where can it be usefully used? Front fills, under balcony, spot fills would be good placements. But when you put 2 on a stick with only 15 degrees of vertical dispersion and an array height of only 16 inches, how large of an area can you realistically cover?”

Again the marketing of these arrays does not explain what actually happens, our span of hearing (20 to 20,000Hz) means that the wavelengths involved span a 1000:1 range in size and the upshot is that the perfect source 16 inches tall, the 15 degree pattern present up high widens to about 90 degrees at 850Hz as the frequency falls and continues to widen as the frequency falls. 

Clearly as one moves from within the pattern to outside of it, the spectrum changes dramatically  but if one had a constant directivity source, the spectrum stays essentially constant while the SPL changes, thus a wide band CD source can have a much more benign behavior, the trick is making one that is constant over a wide band and doesn’t have the interference patterns lobes and nulls.  The 11 foot length Tim mentions would give around a 90 degree vertical pattern (-6dB) at 100Hz if it were acoustically perfect.

Fwiw, the J1 has a VERY powerful low frequency section and a smallish CD horn at its center, the intention was one could do a large spaces without a subwoofer.    There are a number of outdoor stadiums that use one or two for the entire venue, even a few large Churches use a pair of them indoors.   
A   J-3 is a more powerful, smaller and a lighter box that is used with a separate subwoofer.   

While we have elected to focus on stadiums, that is because of the rider issues and the massive cumulative marketing of line arrays, not because one can’t do live sound with point sources.  With the stadium area, there are no riders and they already have concert style rigs installed to compare to side by side. 
By this football season, we will have sound systems in more than half of the 100,000 seat stadiums in the USA, not bad for essentially no advertising.

If you have headphones on your computer, there are a couple videos I took yesterday which might illustrate these point sources.  The first one is the playing field (1) J3 when they were fiddling with the subwoofer level so you can hear it with and without a sub (using the lf section of the Caleb for the sub), you can also hear the wind hitting the microphone on my canon vixia r300 so ignore that.
 
https://www.dropbox.com/s/c7xc3gi9dmcevhn/20140805135418.mts

https://www.dropbox.com/s/mxa64hkkhkk07vj/20140805133848.mts

Here are a couple with the whole system on (not using the single J3 field speaker)

https://www.dropbox.com/s/gwlxss1uxioi4mq/20140805115158.mts

At the 50 yard line (in the pattern of the side J3 and J4)

https://www.dropbox.com/s/1868goglj7k5n6f/20140805183020.mts

At 750 feet from the speakers (in the pattern of the Caleb);

https://www.dropbox.com/s/o0xlb17x8hhgekm/20140805120442.mts

All of the full range speakers fit behind the Hawkeye, there are 4 BC-415 subwoofers to the right side of them.  The result is a -3dB point below 30Hz and a comfortable operating level of 97dBa slow at 800 feet.

Here are a couple more from a few other stadiums.

https://www.dropbox.com/s/oyosfc3adc6j1du/20130723135350.mts

On a windy day at LSU with my daughter;

https://www.dropbox.com/s/dz224imtchuohi4/20130723145400.mts

A smaller J3 system;
https://www.dropbox.com/s/tnsw5mb4v5vdlwq/20120726122124.mts

Best,
Tom Danley

[Peter Morris]

Hi Tom,

I’ve been giving Ivan a bit of a hard time about the suitability of your boxes for contractor’s, so thanks for posting the impressive videos of the football stadiums. FWIW here is a video of one that I have done in the past – capacity 60000.

http://www.youtube.com/watch?v=nCqPa8_ZfiM

This was the actual match, and I had to supply a system for the entertainment before the main game started. The only place the speakers could be position was around the edge of the field. We had only 5 minutes to remove the entire system, and only 2 weeks notification to prepare for it.

I can also remember suppling a speaker system for an England V’s Australia cricket match (picture below take from the approximate speaker position).  The only place we could put the speakers was inside the steel lattice legs that supported the video screen.  We hung EAW KF 750s six or seven deep in a gain shaded (line ?) array; the tricky bit was manually passing each box through the steel lattice that made up the support structure and flying them one row at a time.

These are just a couple of examples of the logistical problems sound contractors face, and why we like 40 – 80 kg line-array boxes in 2014, even though they are not perfect.

What we all want is a light weight, flexible, saleable array that behave like a point source, without the 6dB loss over distance … 

[Marjan Milosevic]

Hi Tom,

I’ve been giving Ivan a bit of a hard time about the suitability of your boxes for contractor’s, so thanks for posting the impressive videos of the football stadiums. FWIW here is a video of one that I have done in the past – capacity 60000.

http://www.youtube.com/watch?v=nCqPa8_ZfiM

This was the actual match, and I had to supply a system for the entertainment before the main game started. The only place the speakers could be position was around the edge of the field. We had only 5 minutes to remove the entire system, and only 2 weeks notification to prepare for it.

I can also remember suppling a speaker system for an England V’s Australia cricket match (picture below take from the approximate speaker position).  The only place we could put the speakers was inside the steel lattice legs that supported the video screen.  We hung EAW KF 750s six or seven deep in a gain shaded (line ?) array; the tricky bit was manually passing each box through the steel lattice that made up the support structure and flying them one row at a time.

These are just a couple of examples of the logistical problems sound contractors face, and why we like 40 – 80 kg line-array boxes in 2014, even though they are not perfect.

What we all want is a light weight, flexible, saleable array that behave like a point source, without the 6dB loss over distance … 

Dont forget to add self levitating :-)

[Peter Morris]

Dont forget to add self levitating :-)

That should be easy for Tom to add to his speakers ... I think he has the patent on that   
http://www.google.com.au/patents/US5036944

[Mike Hedden]

Hi Tom,

I’ve been giving Ivan a bit of a hard time about the suitability of your boxes for contractor’s, so thanks for posting the impressive videos of the football stadiums. FWIW here is a video of one that I have done in the past – capacity 60000.

http://www.youtube.com/watch?v=nCqPa8_ZfiM

This was the actual match, and I had to supply a system for the entertainment before the main game started. The only place the speakers could be position was around the edge of the field. We had only 5 minutes to remove the entire system, and only 2 weeks notification to prepare for it.

I can also remember suppling a speaker system for an England V’s Australia cricket match (picture below take from the approximate speaker position).  The only place we could put the speakers was inside the steel lattice legs that supported the video screen.  We hung EAW KF 750s six or seven deep in a gain shaded (line ?) array; the tricky bit was manually passing each box through the steel lattice that made up the support structure and flying them one row at a time.

These are just a couple of examples of the logistical problems sound contractors face, and why we like 40 – 80 kg line-array boxes in 2014, even though they are not perfect.

What we all want is a light weight, flexible, saleable array that behave like a point source, without the 6dB loss over distance … 

The venue pictured here is similar to several stadiums we've done where a single J1 with lateral fills or two J1's do the job. Also while I certainly don't know the level's expected at a cricket game, our installs are American football demand the system can sustain 100+dBA.
Regarding the 3dB/doubling reference, there simply aren't any of the tour cabinets that exhibit this, certainly not over multiple octaves. 
The best real world example I can think of is our Penn State demo a few years back.  108K seats with a maximum coverage distance over 800'. At the time of our demo the existing system was a two year old VLA system installed by Clair Brothers.  Clair had high level personnel on site when we did our demo.  At the 800' listening position  we switched from a single J2 to the large VLA rig.  If there was 3dB/doubling going on at this distance the VLA should have been much louder but instead it sounded like the VLA rig took a giant step backwards.  The level was way down and and somewhat unraveled. The impression that demo made resulted in us doing a new system which will be premiered this season and if not more important, Roy Clair loves Danley!

Mike Hedden
Danley Sound Labs

[TJ (Tom) Cornish]

The venue pictured here is similar to several stadiums we've done where a single J1 with lateral fills or two J1's do the job. Also while I certainly don't know the level's expected at a cricket game, our installs are American football demand the system can sustain 100+dBA.
Regarding the 3dB/doubling reference, there simply aren't any of the tour cabinets that exhibit this, certainly not over multiple octaves. 
The best real world example I can think of is our Penn State demo a few years back.  108K seats with a maximum coverage distance over 800'. At the time of our demo the existing system was a two year old VLA system installed by Clair Brothers.  Clair had high level personnel on site when we did our demo.  At the 800' listening position  we switched from a single J2 to the large VLA rig.  If there was 3dB/doubling going on at this distance the VLA should have been much louder but instead it sounded like the VLA rig took a giant step backwards.  The level was way down and and somewhat unraveled. The impression that demo made resulted in us doing a new system which will be premiered this season and if not more important, Roy Clair loves Danley!

Mike Hedden
Danley Sound Labs

OK Danley crew - you've clearly made your point here, several times at least.  Your products are awesome when they're already hanging, but until you finish your world conquest and put a single box system in every venue, there are a few of us who will have to juggle logistical challenges that require a system that is not an 800lb monolithic block.   This was Peter's point, and reflects many others' reality as well.

I appreciate the technical insight of Tom and Ivan, but I think we can put the marketing rolodex away now.

[ProSoundWeb Community]