General Product Description:

The EVX-180B low-frequency transducer is designed for professional

sound reinforcement or studio monitoring applications that require

maximum output with low distortion. The EVX-180B woofer provides unprecedented power capacity, linearity

and excursion, made possible by the HeatWick® total-thermal-engineering design. The proprietary HeatWick design actually “wicks” heat away from the voice coil, significantly increasing power handling and long-term reliability. 

     A special frame extension and

elongated pole piece provide a metal surface with close proximity to

the entire length of the voice coil, providing a major heat-transfer path.

Also, the 100-mm (4-in.) diameter voice coil is longer than conventional

medium efficiency woofers to give additional power handling and virtually

eliminate dynamic-range power compression.

Additionally, a Flux Demodulation Device (FDD™) reduces distortion

in the critical mid-band by providing a “short circuit” effect to prevent

amplifier-signal modulation of the static magnetic field.

A ribbed, Kevlar® fiber composite cone with an extremely high

stiffness-to-weight ratio and exceptional strength gives the EVX-180B

increased resistance to cone collapse and deformation, without

sacrificing efficiency.

Architects’ and Engineers’ Specifications:

The low-frequency transducer shall have a nominal diameter of 460

mm (18 in.), overall depth not greater than 198 mm (7.92 in.), and weigh

no more than 11 kg (25 lb). The frame shall be made of die-cast aluminum

to resist deformation. The magnetic assembly shall have an extended

pole piece to reduce inductive variances with excursion, and provide a

symmetrical magnetic field at the voice-coil gap. Two aluminum rings

shall encircle the pole piece above and below the magnetic gap, and

shall have internal diameters concentric with the internal diameter of

the steel top plate. The upper ring shall be part of the loudspeaker

frame. Both rings act to reduce flux modulation and provide a heat

transfer path from the outer diameter of the voice coil.

The voice coil shall be 100 mm (4 in.) in diameter and 20 mm (0.8 in.)

in winding length, and shall be made of edge-wound aluminum ribbon.

When centered in the magnetic gap, the voice coil shall produce a

force of not less than 21.9 newtons (tesla-ampere-meters) with a dc

current of 1 ampere. Performance specifications of a typical production

unit shall be as follows: measured sensitivity (SPL at 1 m (3.3 ft) with

1-watt input, 100 to 800 Hz pink noise) shall be at least 96 dB. The

half-space reference efficiency shall be at least 3.0%. The usable

frequency response shall be 20 Hz to 2,000 Hz, and the nominal

impedance shall be 8 ohms. The rated power for the loudspeaker shall

be 1,000 watts continuous power.

The low-frequency transducer shall be the Electro- Voice® EVX-180B.

Directional Characteristics:

The directional characteristics of the EVX-180B in the TL3512 256-liter

(9-ft³) vented enclosure were measured by running a set of polar

responses in EV’s large anechoic chamber. The test signal was

octave-band-limited pseudo-random pink noise centered at the ISO

standard frequencies. The curves show horizontal (side-to-side) dispersion when the enclosure’s long axis is vertical. The vertical (up-and-down) polar responses deviate only slightly from the horizontal responses due to box geometry. Typical data is provided in Figures 1 and 2, which indicate 6-dB-down beamwidth versus frequency and directivity factor, respectively, for an EVX-180B in the TL3512 enclosure. 

Electrical Connections:

    The EVX-180B is fitted with a pair of chrome-plated, frame-mounted connectors with color-coded ends. Electrical connection is made by pushing down, inserting wire completely through the rectangular slot and releasing pressure. One conductor of #9 AWG stranded, #8 AWG solid, a pair of twisted #15 AWG stranded or a pair of #14 AWG solid conductors will fit. A positive electrical signal applied to the red (+) terminal will displace the cone away from the magnet, thus producing a positive acoustic pressure. 

Recommended Enclosures:

    The most extended bass, lowest distortion and best control is usually realized in properly designed vented enclosures. In such designs, the vent, or port, actually provides the lowest octave of output. The vent is driven to full acoustic output by a relatively small motion of the speaker cone itself, acting through the air contained within the enclosure. The excursion of the EVX-180B at these frequencies is much reduced compared to sealed or open-back enclosures, directly reducing harmonic distortion and the possibility of speaker “bottoming.” The maximum output is limited by either: (1) the long-term thermal power-handling capacity or (2) the speaker’s maximum cone-excursion capability, whichever occurs first.-excursion capability, whichever occurs first.

     The previous information and some more specs can be found at:  https://products.electrovoice.com/binary/EVX-180.pdf