GLL Loudspeaker File Format

Precise Modeling of Sound Sources

Working on the simulation of sound systems and room acoustics since the early 1980's, the founders of AFMG have always been convinced that accurate modeling of loudspeakers is the key to precise acoustic simulation results. – The fast adoption of the first EASE versions throughout the pro-audio industry proved them right: the advancements made in loudspeaker technology were accompanied by the rapid growth of the open EASE loudspeaker database!

The technical expertise and scientific approach of AFMG, along with the friendly, trustworthy attitude shown towards all customers, has led to many ongoing, close cooperations with the pro-audio industry. AFMG has provided consultations and support for professional loudspeaker measurements and, in return, benefited from the experience of manufacturers and their demand for new software features to support the functionality of innovative products.

This continued research and the strive to always implement the technical solution thats provides the best model of real-world solutions led to the development and release of AFMG's award-winning* GLL concept of loudspeaker data in 2006. The release of EASE version 4.2 in March, 2007 made the innovation available to EASE users worldwide.

Formerly, all loudspeaker file formats had used a fixed and limited, tabular format to store only the most important data. This had been adequate to the processing power of computers at that time - never though to the demands of the physical models.

The radically new approach of supplying loudspeaker data in a flexible, expandable, and adaptable description language comparable to modern XLM formats immediately provided a break-through for the new GLL format. This was linked to the success of line arrays in the market which, using traditional tabular file formats, could not be modeled accurately at all. - The use of exact phase data in the GLL now allowed modeling of such complex sources with high precision.

The GLL format also introduced many additional enhancements apart from the acoustical aspects. Including specifications and logical connections for mounting and rigging hardware, weight, center of gravity and other important elements like electrical filters makes the GLL the most advanced and the most realistic loudspeaker file format available.

While all other loudspeaker file formats have adhered to the rough approximations dictated by fixed, tabular file formats, AFMG has continued development of the GLL, underlining its leadership in accurate electro acoustic modeling. EASE SpeakerLab is AFMG´s software tool used to create, edit, and view loudspeaker models (GLL files) for use with the EASE family of simulation products: EASE, EASE Focus 3, EASE Address, EASE Evac, and FIRmaker.

* The JAES paper "Methods and Limitations of Line Source Simulation" received the AES Publications Award 2010.

Loudspeaker File Format – Comparison Table

Feature	Ulysses UNF	CLF	EASE GLL
Data Type	Fixed Data Table	Fixed Data Table	Advanced Description Language
Balloon Symmetries	Full Half Quarter	Full Half Quarter	Full Half Quarter Axial
Angular Resolution	5° 10°	5° 10°	Any 1° - 90°
Frequency Resolution	1/1 Octave 1/3 Octave	1/1 Octave 1/3 Octave	Any 1/1 Octave to 64k Impulse Responses
Phase Data		limited to averages of 1/3 Octaves	up to 64k Impulse Responses
Multiple Transducers		limited
IIR/FIR EQ and Crossover Filters
Provide Manufacturer Presets
User Configurable Setups
Input Configurations and Variants
Line Arrays
Column Speakers
70 V / 100 V Systems
Clustering of Speakers
Customization by Plug-In DLL
Precise Numerical Optimization (FIRmaker)
Listed Manufacturers *		26	122
Database Updates (last 3 years) *		2	78