For customer orders, contact the customer service department at. An introduction, part 1 by bjorn kolbrek this author presents a twopart introduction to hornstheir definition, features, types, and functions. Aes elibrary a generalized horn design to optimize. He is one of the developers of the constant directivity horn design with several patents of biradial horns from companies like jbl, and electrovoice.
This approach yields good loading characteristics and reduced harmonic distortion. It is this directivity control aspect upon which we will focus our attention for this article. The basic idea is to take an oblate spheroidal os waveguide. Mar 06, 2014 constant directivity speakers using waveguides. Horns are widely used as antennas at uhf and microwave frequencies, above 300 mhz. These irresponsible marketing terms loosely refer to horn directivity. The presented program ath41 can be used to design constant directivity horns of various shapes. This is off axis measurements taken myself, as far out as 45 degrees, the response is remarkably flat ou. Speakers flagship design for decades, so naturally we understand the attraction to this approach, and the popularity amongst surge in manufacturers and diy hobbyists alike. The practical aspects of horn design will not be treated in this article. View and download electrovoice constantdirectivity horn hp1240 specifications online.
It typically consists of a short length of rectangular or cylindrical metal tube the waveguide, closed at one end, flaring into an openended conical or pyramidal shaped horn on the other end. This class of horns was patented for directivity control by sidney e. Radiation patterns, permittivity, directivity, and gain october 12, 2016 by mark hughes antennas allow information to be transferred to distant locations. A constant directivity acoustic horn generally comprises a throat entrance and a mouth exit joined by continuous rigid walls. With all models the horizontal coverage pattern is precisely controlled over a frequency range. Electrovoice constantdirectivity horn specification sheet. Furthermore, excellent loading is maintained to a low frequency of hz. If the response changes as you move about it is not constant. The constant directivity horn design provides excellent sound coverage throughout the typical frequency range of speech. In the last three years, constant directivity horns have virtually replaced the older radial and multicellular types in largescale speech and music reinforcement systems. Keeles paper set forth the relationships between mouth size, frequency and coverage angle, providing a basis for many future developments of horn design.
The directivity of a speaker is an important characteristic when defining the size of the listening zone, and it determines how the frequencies will balance, depending on the position of the listener. The bottom graph is the response 45 degrees off axis. Due to the design of the throat section, this new waveguide will admit and propagate a oneparameter wave when it. Rugged enclosure design for optimal acoustic performance wide dispersion constant directivity horn for consistent sound dispersal choosing the right transducer can have a considerable impact on the overall sound of a speaker and its not a task our team took lightly. Jan 24, 2020 the need we want to satisfy is the constant directivity. From design and manufacturing to the stage or studio. On loudspeaker directivity part 1 article by jeff poth ive talked a lot about directivity in these pages, particularly in my oswg building oblate spheroid waveguides and heil amt1 and the heil horn articles. This constantdirectivity loudspeaker offer exact positioning flexibility. A method forwarded by us to perform such analisys will be. Terminology the article includes the following termi. Many efforts have been made to solve these directivity issues, especially in terms of tweeter design hemispherical diaphragms, acoustic lenses, horn drivers, etc, to try to counteract their natural hyperdirectivity. A highfrequency constant directivity horn including a relatively large throat driver and a relatively large throat for receiving sound from the driver, further includes a pair of vanes mounted wholly within the throat, respectively above and below the longitudinal axis in a vertical plane, for effectively dividing the throat into three smaller pseudo horns for directing and shaping sound. First trials of active horn speaker whats best audio. Another may be to provide some control over the radiation pattern of the driver attached to the horn.
There is no such thing in physics as longthrow or shortthrow horns. For instance, 90 in a horizontal plane by 40 in a vertical plane, or 60 by 40, and so on. The federal signal am30 is an 8 ohm constant directivity, reentrant speaker that is ideal for most public address or paging applications. May 24, 2010 another may be to provide some control over the radiation pattern of the driver attached to the horn. At this point secondary flanges are added to minimize. Directivity is the term used to describe the way a speakers frequency response changes at off axis angles.
A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Design of highdirectivity compactsize conical horn lens. Horizontal and vertical dispersion angles are precisely controlled over a broad frequency range. Saxophones trumpets french horns tubas etc obey this rule. At any point throughout the horns coverage angle, the quality and decibel level of a sound emitted remains constant within 6db. Constantdirectivity horn hp1240 horn pdf manual download. The design of these speakers takes the form of a woofer with a horn loaded tweeter. Having constant beamwidth in both the vertical and horizontal directions, and an unprecedented high directivity index, these horns became the model for virtually allnew horn designs for the next decade.
In the second part of this antenna basics series, you will learn more about the physics of how antennas work. Clearly, bens speaker design deviates considerably from my original lxmini. The novel feature of this new horn is that its apparent apices for the horizontal and vertical planes are in the same physical location regardless of coverage angle for the horizontal or vertical plane. Compared to the reference ii series, the new horns have incredibly even, wide, off axis dispersion, almost as if it were design for constant directivity, anyone have any details on the design. Constant directivity horn hp1240 horn pdf manual download. Understanding horn directivity control prosoundtraining. Despite the low price of the xt1464 it is a very advanced horn design.
I would say 2030 people recognized the lxmini design influence and at least half a dozen have built lxminis or orions. This horn has an even 120o horizontal and 60o vertical coverage angle for all speech reproductions. This diagram shows the on and off axis response for a horn which i designed. The need we want to satisfy is the constant directivity. T his article deals with the theory of acous tical horns, as it applies to loudspeakers. Cd series feature the beamwidth control advantage of a constant directivity horn along with the benefit of exceptional high output as a result of the extended air column reentrant design. In the last three years, constant directivity horns have virtually replaced the older radial and multicellular types in largescale speech and music. Highfidelity uniformdirectivity loudspeakers pi speakers. It is a conventional, radial, constant directivity horn design. It combines constantdirectivity with superior engineering design, achieving extraordinary performance with quick and easy installation.
The other horn, xt1464 from 18 sound, is an elliptical constant directivity design and goes a bit lower. Lots of people are experimenting with waveguides and constant directivity loudspeakers these days. S2ba aluminum adaptor converts screwon driver to accept a bolton horn. The horn compression driver is an ingenious dual diaphragm design by alex voishvillo for extended high frequency coverage and low distortion at high output levels. The user shall be able to rotate the horn in 4 directions as required by the application. The tweeter is generally a compression driver, but does not have to be.
This horn has an even 120 horizontal and 60 vertical coverage angle for all speech reproductions. All dsr, dxr, dbr and dxs transducers were meticulously selected and thoroughly. A wide directivity speaker is typically thought of as one that maintains amplitude sound pressure level, spl consistency between the on and off axis sound. Geddes 4, that gave an explanation of which phenomena are at the origin of mouth diffraction effects and showed even that known the velocity distribution at the horns mouth, the far field pressure can be calculated. As we know, the directivity of a horn is controlled down to a frequency that has a wavelength comparable to the horn mouth. Hp64m transplanar constantdirectivity horn general product description the electrovoice model hp64m is a widerange, flatfront, highfrequency, constantdirectivity horn. The peavey 22, 22a, 22t, 22ti, 22xt, rx22, 44t, and 44xt compression drivers require this form of high frequency equalization when used on our constant directivity high frequency horns, or for that matter, any manufacturers constant directivity high frequency horn. Am30 audiomaster public address 30 watt speaker federal. Generically they are called constant directivity horns. Presented at udio the 107th convention 1999 september 2427 newyork. Oct 25, 2017 compared to the reference ii series, the new horns have incredibly even, wide, off axis dispersion, almost as if it were design for constant directivity, anyone have any details on the design. Presented at the 107th convention 1999 september 24 27. In 1975 don keele presented a paper at the 51st convention of the audio engineering society that introduced the modern constant directivity horn.
On loudspeaker directivity part 1 article by jeff poth. Estimating directivity and gain of antennas article pdf available in ieee antennas and propagation magazine 404. Room acoustics sound field control other designs system design. There are a few different types of horns, but the one we are interested in is the constant directivity horn. The flatfront design makes the hp64m suitable for all modern boxed and clustered systems. As with classic radial horn designs, the sidewalls are straight, but in two flange sections. In the low end, the idea of coupling several units to simulate a much bigger loudspeaker has been in use for quite some time.
There are a few different types of horns, but the one we. The industrys only constant directivity reentrant horn, cd series horns from atlasied provide greatly improved uniform sound coverage compared to conical designs. Synergy calc v5 updated by bill waslo, march 2014 a calculator for cutting dimensions and build instructions of wooden constantdirectivity rectangular conical waveguides wantiwaistbanding second flare. A horn antenna is used to transmit radio waves from a waveguide a metal pipe used to carry radio waves out into space, or collect radio waves into a waveguide for reception. The audio industry has spent many decades on the design of acoustic horns with defined areas of coverage. Due to the need to design horn systems capable of improved efficiency and directional. Where the wavelength of the sound is larger than the mouth dimensions the horn has little control over directivity. The problem is that its impossible to have a constant directivity for all audible frequencies. Nor do i know that constant directivity over the whole frequency range is optimum. Electrovoice constantdirectivity horn hp1240 specifications. Constant directivity horn model 340 the gaitronics model 340wideangle, constant directivity is designed to produce intelligible communications over a broad area. The new horns polar patterns are that of a constant directivity type horn.
This gives an extremely high efficiency tweeter, over 100 db sensitivity, with good directivity and excellent micro and macro dynamics. Hp64m transplanar constant directivity horn general product description the electrovoice model hp64m is a widerange, flatfront, highfrequency, constant directivity horn. It is essential to rescale a smaller horn for the next 3 octaves. The angle between them therefore remains constant and the dispersion pattern remains constant over the usable bandwidth. By designing constant directivity highfrequency horns large enough to match the woofers. Related to horns mouth another very important work was made by e. At any point throughout the horns coverage angle, the quality and decibel. Combining cd series horns with the pd75t, pd60t or pd30t.