Vertical stacking is there a limit?

[telecopy]

Sweet Jesus if I had 10 grand I'd stack 8 of those no problem

That would be awesome!

 

[JWH91]

That would be awesome!

If they were all 8 ohm my lh1000 could do it, it would be severely underpowered but at least each cone would rumble

 

[Lobster11]

The Dead Wall of Sound worked well enough, but it wasn't at all practical. They needed two of them, one for the gig they were playing, the other leap frogged ahead to the next gig, because it took two days at least to set it up.

Actually, it's a myth that they had duplicate sound systems: They had duplicate scaffolding, which was set up in advance by the "leapfrogging" crew, but only one sound system.

 

[telecopy]

If they were all 8 ohm my lh1000 could do it, it would be severely underpowered but at least each cone would rumble

Notice the new Nebula finish Bag End S10 is a neo driver. They are shifting to neo finally. I think the S12 infra processor equipped powered cab is as well.. That 12 goes down to 30 hz. but is a sub. Only goes to 95 hz. Probably costs like $2500.
I've got two S10 red carpeted cabs. They're tiny and sweet.

 

[agedhorse]

Notice the new Nebula finish Bag End S10 is a neo driver. They are shifting to neo finally. I think the S12 infra processor equipped powered cab is as well.. That 12 goes down to 30 hz. but is a sub. Only goes to 95 hz. Probably costs like $2500.
I've got two S10 red carpeted cabs. They're tiny and sweet.

Note the maximum SPL using the processing for low frequency extension greatly lowers maximum SPL AND reduces power handling. No free lunch on this aspect, Bag End had written some very good whitepapers explaining the process.

 

[JWH91]

My tiny brain ain't understanding, dumb it down

I understand the internal power but raising the spl how?

 

[agedhorse]

My tiny brain ain't understanding, dumb it down

I understand the internal power but raising the spl how?

LOWERS the SPL because of the additional power to reproduce where the driver is naturally less sensitive PLUS the reduced power handling as frequency fall.

You give up maximum SPL to gain low frequency extension.

There are applications where this is good, but loud bass guitar is not one of them IME.

 

[JWH91]

LOWERS the SPL because of the additional power to reproduce where the driver is naturally less sensitive PLUS the reduced power handling as frequency fall.

You give up maximum SPL to gain low frequency extension.

There are applications where this is good, but loud bass guitar is not one of them IME.

Ahh learning is fun

 

[Downunderwonder]

To generate successively lower frequency requires that the woofer travel further for the same pressure of sound to be generated. You can end run it with reflex box action but that catches up with you too.

 

[agedhorse]

To generate successively lower frequency requires that the woofer travel further for the same pressure of sound to be generated

The woofer moves slower as the frequency decreases.

 

[Downunderwonder]

The woofer moves slower as the frequency decreases.

And by moving more slowly it generates less pressure. To equalize the pressure it has to carry on out further in the same time ie cover more ground each cycle ie faster.

Or I could be much mistaken, for not the first time.

 

[agedhorse]

And by moving more slowly it generates less pressure. To equalize the pressure it has to carry on out further in the same time ie cover more ground each cycle ie faster.

Or I could be much mistaken, for not the first time.

So, for equal power, a woofer tends to reproduce 100Hz-1000Hz at the same SPL. How does your theory explain this?

 

[Downunderwonder]

So, for equal power, a woofer tends to reproduce 100Hz-1000Hz at the same SPL. How does your theory explain this?

Less cycles per unit time balances out the extra energy expended per cycle?

 

[Jeff Scott]

I always thought the Bag End ELF concept was pretty cool, running below the FS of the driver in a sealed box. But, yeah, the efficiency is way down there but this system (with its associated electronics) is worth that trade-off in the right situation.

 

[MYLOWFREQ]

sky is the limit. it is the ceiling indoors.

 

[Jeff Scott]

sky is the limit. it is the ceiling indoors.

The Akron Civic Theatre (one of only a handful of Gothic cathedral theatres) has a sky ceiling.

 

[J-Bassomatic]

The Akron Civic Theatre (one of only a handful of Gothic cathedral theatres) has a sky ceiling.

So many great concerts there under that sky!

 

[agedhorse]

Less cycles per unit time balances out the extra energy expended per cycle?

It's still tha same area under the curve.

I will post more later, because there are 2 principles depending on what you are looking at

 

[beans-on-toast]

The purpose of any live speaker system is to cover the audience with clarity and at th same volume. Not easy to achieve.

In a large venue, they use line arrays. Line arrays are never as simple as a vertical stack. Often there are two horizontal woofers as well as other drivers. Multiple arrays are used. More and more, stage speakers are minimal or props. Smaller venues are optimized by scaling the line arrays down. Without PA support, this is scaled down to one or more speaker cabinets. Every option has challenges to overcome.

This is an interesting high level overview:
Line Arrays Explained |

 

[agedhorse]

The purpose of any live speaker system is to cover the audience with clarity and at th same volume. Not easy to achieve.

In a large venue, they use line arrays. Line arrays are never as simple as a vertical stack. Often there are two horizontal woofers as well as other drivers. Multiple arrays are used. More and more, stage speakers are minimal or props. Smaller venues are optimized by scaling the line arrays down. Without PA support, this is scaled down to one or more speaker cabinets. Every option has challenges to overcome.

This is an interesting high level overview:
Line Arrays Explained |

Line arrays are not the best solution (or the only solution) where the venue is wide and not deep, or where the seating arrangement does not fit with the primary characteristics of a line array format. For example, in a 3/4-arena configuration, it's more common to use an exploded center cluster or a cluster distributed in a concentric arc around the thrust. ESPECIALLY where the house is wide and not deep. We see this a lot in churches and music venues/theatres seating between 250 and 750 seats. Another example is an in the round venue where there may only be 30' of depth to any seating area, another example of the use of a distributed array simply for the coverage.

Other examples that I have worked on include large stadiums with open roofs, basket ball arenas that do not want the impact of long arrays embedded in a center score/display board. These types of venues, especially if they are acoustically very live, often benefit from distributed arrays configured in concentric rings with appropriate zone delay/processing. The benefits of this approach include bringing more seats into the near-field range, as well as being able to shut off zones that are not in use (especially the high perimeter ring of nosebleed seats) which reduce reverberant energy elsewhere in the venue.

Line arrays are good for a lot of things, and benefit from easier rigging, BUT they are absolutely not the best solution for every situation. Anybody who thinks so has not done the math and has not spent any time out in the real world listening to and working on these kinds of systems.