Building better loudspeakers is only the first of many performance challenges that face all audio design engineers. Controlling the sound as it leaves the speaker enclosure is as critical to the performance of the system as the quality of the source component. The goal is always the same: create a consistent sound pattern throughout the desired vertical and horizontal plane without introducing artifacts, while ensuring the full bandwidth and SPL capability of the transducers, and providing a seamless transition from high frequency to low frequency components. JBL engineers relentlessly test new shapes and develop new materials to achieve the desired performance, often inventing new testing methodologies to ensure that nothing is left out of a thorough and rigorous examination of the design. The resulting technology has produced such groundbreaking designs as the Progressive Transition Waveguide, Image Control Waveguide, Slip Stream Port, Radiation Boundary Integrator, and Constant Curvature Waveguide. With multiple patents, and many successful installations in use worldwide, this critical component of JBL technology continues to evolve through our continuous pursuit of better, more accurate sound.

Image Control Waveguide

Unprecedented Detail, Vivid Imaging, 
and a Room-Friendly Broad Sweet Spot

The unique geometry of this waveguide delivers remarkable high frequency detail, imaging, and natural balance at nearly any listening position in a broad range of acoustic environments. Since design of this complexity and level of detail is an iterative process, JBL performs Finite Element Analysis, creating virtual simulations of off-axis response, pattern control, and the blend of the high frequency driver and woofer.

Impressive Imaging and Sound Stage, Exceptional High Frequency Detail, Uniform Directivity for Smooth In-Room Response, Patent Pending Design

Increased High Frequency detail

The Image Control Waveguide was developed for JBL's new flagship M2 Master Reference Monitor and with the introduction of the JBL 3 Series, is now available for the first time in an affordable, compact reference monitor. Its patent-pending design precisely controls the sound emanating from the speaker in the vertical and horizontal planes ensuring the representation of your mix is neutral and accurate at the listening position.


Slip Stream™ Port

Low Frequency Port

The patented JBL low frequency port design works in concert with the 3 Series woofer for accurate bass response at all playback levels. The double-flared shape of the port is precisely calculated for greater low-frequency extension and reduced turbulence.


Progressive Transition™ (PT) Waveguides

Balanced frequency response, pattern control, and distortion, improved sound reproduction.

Progressive Transition Waveguides provide excellent coverage control and are rotatable so the loudspeaker system can be used in either the vertical or horizontal orientation.

An Introduction to Progressive Transition Waveguides:

The modern constant-directivity horn has evolved slowly since its introduction over 25 years ago. Advances in horn design have been primary evolutionary in nature. To achieve balanced response of all parameters, JBL Professional started with a clean sheet of paper and developed Progressive Transition (PT) Waveguides.

Progressive Transition waveguides are unique because a single mathematically-continuous surface defines the waveguide from transducer- throat to waveguide-mouth. The distinctive feature is the lack of a traditional diffraction slot. Instead the sidewalls transition smoothly from the driver throat through to the square or rectangular mounting flange.

Progressive Transition Waveguide Families

PT waveguides are grouped into two families. The first is “compact”, and second is “optimized cover- age/rotatable”. Compact PT waveguides balance performance in favor of small overall package size. Frequency response is optimal, distortion is superbly low, depth is minimized for use where a shallow enclo- sure is required. Beamwidth and directivity are optimal in the horizontal plane. Vertical beamwidth and directivity are optimized to provide a good match with JBL low frequency and midrange transducers; however, vertical pattern control does not extend as low as optimized coverage PT waveguides.


VTX V25-II WaveGuide

Improved Wavefront Control

The V25‐II waveguide provides better acoustic loading conditions for the D2 driver, resulting in 10 dB higher sensitivity above 10 kHz. This sensitivity increase means that less high frequency (HF) shelving equalization is required in order to achieve the same acoustic output response and, as a result, there is a significant increase in amplifier headroom. Limiter thresholds can also be adjusted so there is less peak limiting activity and reduced distortion. All of this combines to provide higher maximum SPL and improved system packaging density since there is a better power match when V25‐II is used with Crown Audio IT4x3500HD four channel amplifiers.


Radiation Boundary Integrator™ (RBI)

Improved Broader & More Stable Horizontal Coverage

JBL’s patented Radiation Boundary Integrator combines the high frequency and mid-range so the transition across each band is uninterrupted, undistorted and seamless. A patented, tuned resonant-chamber is integrated into the waveguide itself, effectively eliminating throat-related cancellations due to back pressure from the mid-range section. Our refined RBI waveguide implementation provides improved horizontal coverage - broader and more stable.


Constant Curvature Waveguide

Enable multiple drivers to work together acoustically as a single driver.

The challenge in designing a world-class line array is to create a controlled, coherent coverage pattern regardless of the number of cabinets used in the array. JBL’s Constant Curvature Array Design does that and more. Our waveguide mounts three compression drivers on a continuous arc enabling them to work together acoustically as if they were a single driver, while dramatically increasing the power handling and acoustic output when compared to a single driver system. Additional enclosures can be added creating an uninterrupted, continuous arc with all of the drivers working together seamlessly as if they were one driver on a very long waveguide. This innovative technology provides unprecedented output coherence and stunning, clear high-frequency sound quality regardless of the configuration.


Crossfired Waveguide Technology (CWT)

Even response throughout the frequency spectrum.

Crossfired Waveguide Technology delivers evenly dispersed sound across a wide coverage area without the interference and uneven sound fields produced by the typical approach of two speaker systems firing at cross angles. The dual function CWT Waveguide is loaded with two compression drivers mounted to create a seamless, 160 degree, full bandwidth coverage pattern. Its small footprint provides dramatically improved performance in about one third the space with reduced cabinets, cabling, mounting hardware, setup time, and overall cost.

Wide Coverage Waveguide

The CWT Waveguide features a wide coverage pattern designed to provide seamless horizontal coverage across a full 160°. Based on JBL patented technology, the CWT Waveguide is essentially split in half and loaded with two compression drivers facing in different directions. The waveguide delivers wide angle coverage in a single enclosure, exhibiting no interference, and providing remarkable off-axis response. By eliminating multiple sets of speakers that interfere with each other, the overall fidelity of the system is greatly improved, intelligibility is increased, and a more pleasant listening experience is provided for the audience.


Dual Dissimilar Radiators

Sculpt Consistent Coverage for Every Seat in the House

JBL’s patent-pending Dual Dissimilar Radiators solve a fundamental problem in cinema sound: Each individual cinema speaker interacts differently with room geometry depending on its location, so to deliver an identical sonic experience in every seat, each speaker must radiate a distinct pattern. Compounding the issue, traditional transducers deliver more energy to the closest seats and less energy to the furthest, resulting in inconsistent volume.

Dual Dissimilar Radiator design combines two asymmetric high-frequency drivers with sophisticated DSP that manipulates acoustic interference between primary and secondary radiation patterns, to engineer seamless new coverage patterns that would be impossible with a single transducer. The result? The exact same sonic experience in every seat in the house—front to back, or side to side.

Provide Unprecedented Sonic Uniformity for the Cost of a Traditional System

Engineering Vertical Coverage for Modern Stadium Seating

Raked seating provides an ideal viewing experience, but introduces challenges for uniform sound coverage. Dual Dissimilar Radiator vertical coverage patterns are optimized for slanted stadium seating: Precisely tune your system in minutes, without physically angling drivers. And this improvement is not limited to screen channels; we’ve incorporated Dual Dissimilar Radiators in rear and side surrounds, for the truest reproduction of dialog, music and effects, anywhere in the house.

To learn more about this groundbreaking technology, download our white paper.