Mackie HR624 Owner's Manual - Introduction
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INTRODUCTION
crossover, power amplifiers, and drivers into a
single cabinet, and we’ve taken full advantage of
these benefits in the design of the HR624.
• The crossover point is designed so that the
high and low frequency drivers are fed only
the frequencies they are best able to reproduce.
• The amplifiers are designed to provide
maximum acoustic output from the speakers,
yet minimize the danger of speaker damage
due to overdriving.
• In addition, the amplifiers’ gain and fre-
quency responses are individually
hand-trimmed to compensate for typical
manufacturing tolerances between the
drivers and produce a smooth frequency
response from 52Hz to 20kHz (
±1.5 dB).
Thank you for choosing Mackie Designs’
HR624 Studio Monitors. We realize that monitors
are a critically important tool whether your
application is studio recording, audio/video post
production, hi-fi, or home theater. Knowing this,
Greg Mackie had a simple mandate: Design a
reference monitor with a degree of accuracy and
versatility unmatched by any other in its size and
price category — or any size and price category
for that matter. The mandate was simple, but
accomplishing it was another story!
Investments in Excellence...
To accomplish the task at hand, Greg and the
New Product Development team realized that a
commitment was required in terms of new resources
and new equipment. So we recruited some of the
best speaker and acoustic engineers in the indus-
try to assist in the design of the HR624. And we
invested in some advanced (and need we say
expensive) measurement and analysis tools for
the design team to use.
The result? The HR624 Studio Monitors are
extremely accurate and versatile, loaded with
unique controls that allow you to fine-tune the
sound to match your individual environment
precisely. You’re gonna love these!
What are they? The Advantages...
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. Whew!
There are many benefits to integrating an active
Tweeter
Woofer
Passive Radiator
"H" Brace
Power Amplifier/
Crossover Assembly
Figure 1. HR624 Cutaway side view
Lend Me Your Ears
Exposure to extremely high noise
levels may cause permanent hearing
loss. Individuals vary considerably in
susceptibility to noise-induced hear-
ing loss, but nearly everyone will lose
some hearing if exposed to sufficiently
intense noise for a period of time. The U.S.
Government’s Occupational Safety and Health Ad-
ministration (OSHA) has specified the permissible
noise level exposures shown in this chart.
According to OSHA, any exposure in excess of
these permissible limits could result in some hear-
ing loss. To ensure against potentially dangerous
exposure to high sound-pressure levels, it is recom-
mended that all persons exposed to equipment
capable of producing these levels use hearing pro-
tectors while this unit is in operation. Ear plugs or
protectors in the ear canals or over the ears must
be worn when operating this amplification system
in order to prevent a permanent hearing loss if
exposure is in excess of the limits set forth here.
Duration Per Day
Sound Level dBA,
Typical
In Hours
Slow Response
Example
8
90
Duo in small club
6
92
4
95
Subway Train
3
97
2
100
Very loud classical music
1.5
102
1
105
Patrice screaming at Ron about deadlines
0.5
110
0.25 or less
115
Loudest parts at a rock concert
The HR624
can produce a
maximum SPL of
115 dB @ 1m