Mackie HR624 Specifications

HR Series
 The HR624 studio monitors are high-resolution, two-
way, bi-amplified, active monitors employing a 6th-order
Butterworth system with a built-in rear-firing mass-loaded
passive radiator. They feature a 1-inch aluminum-alloy
high-frequency transducer, a high-precision 6.7-inch die-
cast magnesium frame low-frequency transducer, and a
6-inch x 9-inch elliptical flat piston passive radiator in the
back. The system is composed of a single, compact cabinet
with built-in control and amplifier electronics.
 The high-frequency driver is mounted on a massive,
acoustically non-resonant die-cast zinc exponential
waveguide, which results in wide, controlled dispersion
for high-frequency sounds. The unique passive radiator
design provides smooth response down to 52 Hz.
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The amplifiers found in the HR624 cabinet are an
example of application-specific amplifier design that can
be exercised when designing active speaker systems. The
low-frequency amplifier is rated at 100 watts rms continu-
ous output, and the high-frequency amplifier is rated at
40 watts rms continuous.
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The input panel on the back accepts a line-level input
with balanced 1/4" TRS, XLR, and unbalanced RCA connec-
tors. The connectors face downward so the monitor can be
placed flush against a wall. There is an input sensitivity
control to trim the gain from input to output and adjust for
various input levels. An acoustic space switch adjusts the
bass response to compensate for corner (quarter space) or
wall (half space) placement. A low-frequency switch selects
a high-pass cutoff frequency of 80 Hz, and a high-frequency
switch provides either 2 dB of boost or cut above 10 kHz.
The power mode switch can be used to turn the monitor on
and off, a function that is duplicated with the front panel
switch, or to put the monitor into auto mode, where the
amplifiers revert to standby when no signal is present for
several minutes. The instant a signal appears at the input, the
amplifiers seamlessly come back to life and produce sound.
 The cabinet is constructed using 5/8-inch (16 mm)
thick MDF with a 1-inch (25 mm) thick MDF front panel. An
internal H-brace provides additional cabinet stiffness, and
open cell adiabatic "foam fill" acoustic damping material
absorbs internal reflections.
R E L A T E D P R O D U C T S
HR824 Active 2-Way Studio Monitor, HR626 Active 2-Way
Studio Monitor, HRS120 Active Subwoofer, HRS150 Active
Subwoofer
HR624
Active 2-Way Studio Monitor
Features
Flat frequency response (±1.5 dB, 52 Hz to 20 kHz)
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1" ferro-fluid cooled aluminum alloy dome tweeter
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6.7" mineral-filled polypropylene cone woofer
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Proprietary, acoustically non-resonant high-frequency
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exponential waveguide
6" x 9" elliptical passive radiator for enhanced bass
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performance
40 watt HF and 100 watt LF power amplifiers
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Servo-loop architecture for improved low-frequency
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overload detection
Independent high and low frequency overload detection
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High-strength cabinet constructed with 5/8" MDF
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composite and 1" front board with radiused edges
Internal H-brace for extra rigidity
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High-density adiabatic foam absorbs internal reflections
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Full magnetic shielding
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Balanced XLR and 1/4" TRS, and unbalanced RCA
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input connectors, downward facing
Modified Linkwitz-Riley 24 dB/octave crossover
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Recessed adjustable sensitivity control
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Acoustic Space switch for selecting whole space,
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half space, or quarter space placement
Low-Frequency switch for bandwidth limiting the
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low-frequency response
High-Frequency switch boosts or cuts high frequencies
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Power Mode switch includes AUTO mode
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Front panel mute switch with indicating LED
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Front panel overload indicating LED
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Applications
Near-field studio monitors
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Home Theater surround sound
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