HP640
Constant-Directivity
Horn
General Product Description
The Electro-Voice
®
HP640 is a wide-range, flat-front,
constant-directivity, high-frequency horn. With the
HP640, a horizontal dispersion angle is controlled over
a frequency range of 500 Hz to 20 kHz, and the vertical
angle is controlled from 1.5 kHz to 20 kHz, both with
unusual precision and adherence to the intended angle.
Furthermore, excellent loading is maintained to a low
frequency of 500 Hz.
The flat-front design makes the HP640 suitable for all
modern boxed and clustered systems. A special vaned
waveguide throat detail gives the HP640 unusually
uniform vertical directivity control in the top octaves
when compared to similar 2-inch-throat horn designs.
Architects’ and Engineers’ Specifications
The horn shall be of the constant-directivity type. It shall
produce a horizontal beamwidth (6-dB-down angle) of
60 degrees, deviating no more than 20 degrees from
this angle over the frequency range of 500 to 20,000
Hz. It shall produce a vertical beamwidth of 40 degrees,
deviating no more than 10 degrees from this angle over
the frequency range of 1,500 to 20,000 Hz. In addition,
it shall provide useful acoustic loading at all frequencies
above 500 Hz.
The horn shall be of hybrid fiberglass-and-zinc
construction. The initial throat section shall be
Specifications:
The following specifications are in accordance with or
exceed the AES Recommended Practice for
Specification of Loudspeaker Components Used in
Professional Audio and Sound Reinforcement
(AES2-1984; ANSI S4.26-1984).
Horizontal Beamwidth:
60° (+20°, -10°) (-6 dB 1.6 kHz to 20 kHz)
Vertical Beamwidth:
40° (+20°, -10°) (-6 dB, 1.25 kHz to 20 kHz)
Directivity Factor R
θ
(Q):
17.8 (average 1.6 kHz to 20 kHz)
Directivity Index D
i
:
12.5 dB (+2.0, -3.0 dB)
10 log R
θ
, (average 1.6 kHz to 20 kHz)
Lowest Recommended Crossover Frequency:
500 Hz
constructed on die-cast zinc and shall be integrally
laminated into the fiberglass portion of the horn.
The horn shall possess a throat of 4.9 cm (1.94-in.)
diameter, and its flange shall be provided with four
clearance holes for ¼-20 bolts, located on a 10.2 cm
(4.0 in.) circle for the mounting of the compression
driver. The horn shall be 33.0 cm (13.0 in.) high, 71.1
cm (28.0 in.) wide and 43.7 cm (17.2 in.) long. It shall
weigh no more than 4.3 kg (9.5 lb).
The hor n shall be the Electro-Voice HP640
constant-directivity horn.
Construction:
Polyester resin and glass-fiber laminate integrally
molded to a die-cast zinc throat section. This hybrid
construction assures a rigid driver mount, accurate,
loss-free throat-wave transmission and low total weight
compared to horns of similar size.
Mechanical Connection of Driver:
Bolt on; standard 2" diameter throat, 5" diameter
mounting flange and four clearance holes for ¼" bolts
on a 4" diameter bolt circle.
Recommended Driver:
DH1A, DH2A, DH2As2
Weight:
4.3 kg (9.5 lb)
