EASE modeling graphics

[sdauditorium]

We received a second bid for our upcoming sound system install, and they included a few graphics from EASE based on the speaker setup they felt best worked in our space (mid-size house: seats 592, no balance, proscenium opening of approx. 50' w x 18').

Before I mention the brand/model they chose, I want to know if you think these results are acceptable. I realize it could be a bit better, but we're looking at a $35,000-$37,000 budget. They'd like to install powered cabinets along with a sub per side (flown).

Not knowing all of the specifics, I'd appreciate feedback.

 

[MNicolai]

I don't believe you'll find much here in the way of constructive feedback, not knowing the design nor the method by which the model was produced, nor the constraints that the contractor is under to hit your intended price point. In regards to the EASE model charts -- there many different ways to run simulations in EASE -- more important than the charts shown is the data that was used to establish the room acoustics in the model. Without knowing what that data was or if/how it was verified, nobody here can appropriately assess the quality of the design based on the charts shown.

Setting aside for a moment that they are a competitor of ours, what I will say is that the contractor whose EASE model you've shown does good work. We work with them on a regular basis and their attention to detail is always stellar. If you want to know more about what their EASE modeling is telling you about their design, ask them to walk you through it and I'm sure they can tell you everything you need to know. You can trust that they will be honest with you about their design, what the EASE charts mean relative to the design, and also relative to your budget.

For whatever it's worth, I'd not go shopping their EASE model graphics around. Aside from the proprietary nature of those graphics and the design behind them, soliciting feedback from others can lead to a great amount of confusion without a more comprehensive view of the project goals, constraints, and designs. It's easy for people to criticize a design not knowing the constraints that the design team was working with, especially with the relatively tight budget your project is operating under.

--

Blast from the past, we were talking about this here in our office -- one of the guys here put the original system in some two decades ago when he was working for another contractor in the region.

 

[themuzicman]

It's fairly easy to fudge constraints in any speaker program to make it look good for a client, real world results matter -- I'd go take a visit to other projects they have consulted on just to make sure they do a good job.

Realistically, if they really are just flying a cabinet and a sub per side, and you are in a theater I'd be a little worried that they don't quite "get" how theaters work. If you are doing a lot of just theater stuff, spoken word and all that, you'll want front fills and delay speakers. You want to keep the overall level of volume down, while keeping intelligibility high. With just a L/R system, and no delay or front fill you will have to pump the volume to hit the back (you can see that in the second EASE photo). The other thing that may not be on your radar is on-stage monitoring. If you have a lot of bands, floor wedges, if you do a lot of theater, flown foldback speakers in the wings...

 

[sdauditorium]

If a mod could delete this thread, that'd be great. PM me with questions. Thanks.

 

[museav]

I hate to delete the thread as there are some good responses posted. It is all too easy to misjudge what someone else has done when you don't know the same information the other party knows.

I will offer one comment in that the EASE modeling provided seems to reflect just the direct energy on the defined seating planes. Other than perhaps a wall that helps block the coverage of the stage, there seems to essentially be no room surfaces defined nor the related indirect energy from the speakers considered, just the direct output of the speakers hitting the seating planes. That may be applicable if this was outdoors but I assume it is actually inside a room and the room will definitely affect the intelligibility of the system. Perhaps they turned all the room surfaces and vertices off to make the plots clearer, but otherwise that may also be fine for an initial analysis and speaker selection but I would argue that it makes plots such as the Articulation Loss plot provided of little or no use since the basis for that plot doesn't come close representing the actual conditions or aspects that could be critical to the resulting intelligbility. It is difficult to address factors like the Direct/Reveberant Energy Ratio in the resulting intelligibility if you looking at only the direct sound.

 

[MNicolai]

Based on how we do our own EASE models, I'd venture the guess that the room is more modeled than is shown. We generally don't show architecture in our plan view charts either. We save that for our 3D renderings.

Often we'll generate out a full written report detailing the room acoustics with 2D and 3D graphics from EASE, as well as Excel graphs, but that level of detail tends to be more on projects where we have been hired to perform an acoustic study and is not the level of detail we'd generally go into on a project we're bidding on but have not been given additional fees for for all of the acoustical analysis.

Thus, the roles and responsibilities of a bidding contractor can vary greatly from that of a design consultant. Generally each bidding contractor would not perform their own acoustical analyses as they are not being paid to perform the legwork required to generate those studies.

Just because additional graphics and analyses are not detailed does not mean that they were not taken into consideration during the design. It likely means they just were not provided to the client, which is not unusual absent a full report of room acoustics.

 

[museav]

Based on how we do our own EASE models, I'd venture the guess that the room is more modeled than is shown. We generally don't show architecture in our plan view charts either. We save that for our 3D renderings.

When I was on the contracting side it was quite common to do nothing more than direct coverage plots of seating areas until we actually got the job, and to not do much more than that at all for many projects, so I understand that aspect. However, unless it is an outdoor venue I do not understand the point of presenting Articulation Loss information that does not include the predicted effects of room.

Because the coverage plots all show a pretty significant drop off along the one line downstage I am assuming that is shadowing resulting from line on the plots that seems to represent the proscenium wall and perhaps even a closed curtain. So one wall, or the effects of it, seem clear in the coverage plots. However, none of the plots appear to show any other surfaces or reflect any of the effects on Articulation Loss one might expect from the other room surfaces. Now maybe all the room surfaces are very 'dead' in the speech frequency range, but it seems worth verifying if the Articulation Loss plot presented does include the predicted effect of the room or not, whether the ambient noise level used for the calculation is actually representative, etc.

 

[applstew]

It's fairly easy to fudge constraints in any speaker program to make it look good for a client, real world results matter -- I'd go take a visit to other projects they have consulted on just to make sure they do a good job.

Realistically, if they really are just flying a cabinet and a sub per side, and you are in a theater I'd be a little worried that they don't quite "get" how theaters work. If you are doing a lot of just theater stuff, spoken word and all that, you'll want front fills and delay speakers. You want to keep the overall level of volume down, while keeping intelligibility high. With just a L/R system, and no delay or front fill you will have to pump the volume to hit the back (you can see that in the second EASE photo). The other thing that may not be on your radar is on-stage monitoring. If you have a lot of bands, floor wedges, if you do a lot of theater, flown foldback speakers in the wings...

Before I state anything else I did work for Arrow Audio in the past. That being said I know for a fact that they have worked with numerous theaters and Houses of Worship so I have a strong belief they do understand how they work. My HS theatre sound system was designed and installed by them and we have had no complaints with what was spec'd. They do multiple shows a year and the sound system has performed as it should. One does not need front fills and delays if the system is designed correctly. My HS has one 3 way box and a sub per side and that cover 900+ seats. We also have delays because we have a balcony. It is doable.

 

[themuzicman]

Before I state anything else I did work for Arrow Audio in the past. That being said I know for a fact that they have worked with numerous theaters and Houses of Worship so I have a strong belief they do understand how they work. My HS theatre sound system was designed and installed by them and we have had no complaints with what was spec'd. They do multiple shows a year and the sound system has performed as it should. One does not need front fills and delays if the system is designed correctly. My HS has one 3 way box and a sub per side and that cover 900+ seats. We also have delays because we have a balcony. It is doable.

I'm assuming you're also still in high school? You don't "need" front fills and delays, but they do help a whole heck of a lot to keep overall volume down while keeping intelligibility high. There is no such thing as a "correct" system design, however there are designs that make working in certain spaces a lot better than in other spaces. A single cabinet per side may serve to adequately get noise to every seat, but you're still going to have a lot louder of a signal in the front and a lot quieter of a signal in the rear of house just due to the simple fact that there is no distributed audio. It is a usable system, but hardly an ideal system in my book. Get a little more experience in more than two venues and you'll see what I'm talking about. Just because it "covers" 900 seats doesn't mean each seat is getting a similar auditory experience, which is what other speakers attempt to do.

As an example, I just had a design go up in a 300 seat theater last week and I used 2 flown UPA-1P mains per side, 2 as a center cluster, 1x 650-P subwoofer a side, a smattering of MM4 front fills, and 3 rows of 3 UPM-1P's as delays just due to the fact that a majority of the design was spoken word and I wanted to make sure that every seat could hear the speaker and the volume appeared to be completely natural, eminating directly from the performers mouths. If had the system your auditorium had it would have been too loud to appear as to be natural for the first few rows extreme HL and HR, with questionable center coverage and then most likely at too quiet a level for the last row or two. What you have would get the job done but not in a way that reflects on a theater naturally. If you have delay your room correctly and have enough distributed audio you will never have an audio signal louder than 3dB from your original source material.

Read up on law of the first wave front/precedence effect/haas effect: http://en.wikipedia.org/wiki/Haas_effect

 

[MNicolai]

Gentlemen, there's no need to be argumentative.

The point being made was that it's not possible to judge a company's experience in theatrical sound system design based on a few EASE charts, particularly for a project with a tighter budget than is ideal. Having spoken with designer, I know that they had a much more comprehensive (albeit more expensive) design in mind that just was not possible under the allotted budget.

Given the existing system, the proposed design is still a substantial improvement, despite not being what the designer would ideally have liked to have specified.

I think we all know how it feels to work on a project that we wish could have an extra couple zeroes added to it. As design professionals though, we have to work within the confines of our project constraints, which means that not every project turns out how we would desire them to under ideal conditions, but that does not stop us from making each project the best that we possibly can given the tools, resources, and budgets that are available to us.

In summary, please refrain from judgment of Curt's design. The cursory look you can get at it based on the information in this thread is far from enough to make a thorough, educated opinion.

 

[museav]

I agree that it is all too easy to misinterpret or misunderstand EASE data or design concepts in general without having sufficient understanding of the overall situation. Very often budgets, existing conditiions, Owner requests, etc. willl dictate what is practical or feasible. I have even been put in the position of having a school provide a complete equipment list, defined by someone else for a completely different venue, with the charge to best fit what was defined to a different space. I am certainly not proud of that design other than in being able to create something usable out of what was dictated to us.

Predictive modeling such as EASE, Ulyssses and CATT-Acoustic can be a very powerful and beneficial design tool when used properly, however the results also can be manipulated to support proposed solutions. One common issue I see in the modeling many have offered is predicted coverage results for supposed stereo or LCR systems that show the total coverage of all speakers rather than that for each individual channel, a result that seems to reflect either a basic misunderstanding of such systems or that what is being proposed is not really what it may be held out to be. For example, on another forum someone was asking for input on a proposed design and people were concerned about the coverage that would result for each individual channel of the proposed 'stereo' system. They kept suggesting that the Contractor provide modeling for each channel of the system alone but the Contractor seemed to only want to provide results that showed good coverage, which apparently required both the left and right arrays being active. Whether that was an attempt to 'sell' their design or their simply not understanding the basic concept was not clear but it certainly supported the concerns many had wth the proposed system.