Which version of EASE should I buy - JR, Standard, or Standard + AURA Module ?

In order to assess if a project can be simulated adequately based on the room´s characteristics it is important to know about the different calculation methods used within the different versions of EASE.

AFMG offers three calculation levels within the product family of EASE – the industry standard electro-acoustical simulation software:


EASE JR uses a statistical approach based on Sabine and Eyring formulas for the computation of the reverberation time. 

This method assumes that the sound field inside the room is diffuse. These kinds of sound fields are more commonly encountered in rooms where the absorption is homogeneously distributed over its surfaces, and where its geometry does not propagate concentration of energy in specific directions.

EASE JR is especially helpful:

    • When the project’s focus is the design of sound systems and the evaluation of the system’s performance in the room. In these cases, this calculation method will provide reliable results.
    • For the simulation of the sound system coverage on wide-open areas.
    • For a rough preliminary investigation of more complex rooms to get an initial overview. This can be in the conceptual or preliminary design phase of a project, when you need to weigh the investment of resources as efficiently as possible and need to quickly get a good assessment of the project´s requirements.
    • When the room behaves statistically and its reverberation time can be measured on site to be entered in the program. In these cases you do not need to worry about uncertainties in the selection of the room’s surface materials, or even about the room geometry data.
    • For superficial evaluation of the behavior of early reflections in the room (up to the 3rd reflection order).

    This simplified approach requires the least amount of time and data to obtain answers about the room’s acoustics and the performance of a sound system in the room. It can be seen as a good starting point for performing acoustical and electro-acoustical simulations.

    With respect to the room entry in EASE JR there are no feature limitations compared to EASE Standard. One can fully enter or import a model with a complex geometry in EASE JR. That is why large consulting offices often use EASE JR to draw models that will then have its full room response calculated on powerful server computers running EASE Standard and the AURA Module.

    Typical room examples / use cases are:
    Rooms with little absorption and relatively simple shape, or with geometries that do not propagate concentration of acoustical energy such as conference rooms, typical classrooms, and office spaces with little absorption.
    Note: The coverage and performance of the sound system itself can be simulated in any room or open areas.


    EASE Standard

    EASE Standard is able to calculate the impulse response at specific locations in the room by using ray tracing algorithms. You can choose to perform geometrical ray tracing calculations based on the deterministic image model or the stochastic ray tracing method. This way you can get a more accurate picture of not only of the performance of a loudspeakers’ system but also of the general behavior of the sound in a room.

    This version of EASE provides an intermediate level of calculations for rooms with more complex geometries and uneven distribution of absorbtion. In these cases you would often be expecting local differences in reverberation or audible echoes.

    In addition to the benefits available in EASE JR, EASE Standard is helpful:

    • To design sound systems in acoustically challenging venues where not only the reverberant field plays a role, but also strong discrete reflections.
    • When the assumptions of Eyring and Sabine formulas for the calculation of the reverberation time are not met, and thus ray tracing algorithms are recommended.
    • When advanced acoustical evaluations are the focus in order to analyze and solve acoustical problems.
    • For local analysis of reflections in the room in a manner similar to positioning a measurement microphone on site. This enables you to become aware of obstacles that could remain hidden without enhanced investigation.

    In order to keep calculation times within acceptable ranges, ray tracing algorithms are usually employed only to calculate the early part of the room’s impulse response. The so-called “statistical tail” is then computed and used for the later part. This approach is generally sufficient for rooms where you would not expect reflections with considerable energy in this later part of the impulse response.

    Typical room/venue examples are:
    Stadiums and cathedrals (for reflection analyses only)
    Auditoriums, lecture halls, traditional churches - In addition to the examples for EASE JR.


    EASE Standard + AURA Module

    EASE Standard including the AURA module offers the highest quality of calculations, and is the most flexible simulation solution. AURA is composed of a hybrid ray tracing engine, which uses both: the deterministic image model (cone tracing) and the stochastic ray tracing method. This combination provides the methods needed to perform acoustical simulations for several different types of venues.

    In addition to the benefits of the previous versions, EASE Standard including the AURA module is helpful:

    • When your daily work might involve design-projects for venues of different types and shapes.
    • When you are interested in computing acoustic parameters according to the ISO 3382 standard.
    • For more direct comparisons with measurements on site.
    • When a large number of sound sources and surfaces are expected in the project.
    • To obtain very detailed information on the acoustical behavior of a room even if it has a complex 3D shape, a large volume, non-homogeneous distribution of materials, or if a long reverberation time is expected.
    • For precise prediction of STI and other parameters based on reverberation time in such projects AURA is highly recommended.
    • For more realistic simulation of reflections by considering the surface scattering coefficients.
    • To obtain more accurate full room impulse responses for later auralization of the room using the EARS module.

    The AURA name is an acronym for Analysis Utility for Room Acoustics. Being a 64-bit module that supports multi-threading, AURA can take the most out of powerful modern CPUs with several cores. The engine considerably reduces the calculation times needed for computing full room impulse responses as compared to classical ray tracing algorithms. It is also able to compute responses with much higher realistic density.

    Typical room/venue examples are:
    Concert halls, stadiums, train stations, airports, cathedrals - In addition to the examples for EASE JR and EASE Standard.

    If you are also interested in the benefits the EARS module offers, you will find helpful information in this FAQ:
    When it is recommended to use the EARS module to perform auralization?

    No matter what version of EASE you work with - it will help you to:

    - Obtain professional data assessment and verification. 
    - Explore options and evaluate what works and what does not work.
    - Eliminate costly mistakes and reduce installation time.
    - Meet the requirements for SPL, STI and other demands with minimum effort.

    As with any simulation tool, the key to a relevant result is the understanding of the program and theory and the correct entry of data by the user.

    Note: This FAQ should give you a rough overview, so that finding the adequate solution for your projects will be easier. As there is a multitude of rooms and venues with specific characteristics and different requirements, you always need a thorough evaluation in advance.

    For an overview of the specific features offered within the different versions of EASE and its modules, please have a look at the EASE - Software Versions and Modules website.

    Applies to: