Class
- D Audio Power Amplifiers:
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C |
The
Class-D Audio Power Amplifiers used in all Charles Grecco
products are the culmination of over 12 years of development.
Features include: |
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Compact
size: 4.25 x 4.1 x 1.75" (108 x 105 x 45mm) |
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High
output power: >1000Wrms |
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Wide
bandwidth: <5Hz to >35kHz |
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Low
distortion: <0.02% at 10W output, <0.1% at rated
power |
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High
efficiency: >90% |
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On-board
microprocessor for amplifier control and status
monitoring and communications |
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Full
protection against load faults and thermal stress |
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Isolated
crystal-controlled clock for minimum noise |
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Proprietary
feedback network that minimizes frequency response
errors related to variations in load impedance
These state-of-the-art amplifiers are powered by a companion
switchmode power supply, that also features high efficiency
and compact size. Its switching frequency is specifically optimized to
minimize noise artifacts in the audible range.
Each powered loudspeaker also features a DSP-based active crossover
driving its array of up to 4 amplifiers. This DSP provides
steep crossover slopes to minimize loudspeaker out-of-band response
anomalies and advanced pattern control. It also provides additional time-alignment and
fine equalization of all drivers in the array.
John Levreault
Orvelle Technologies, Inc.
Amplifier Design |
Woofers:
Vance Dickason called long time friends and woofer designers
Patrick Turnmire, and Enrique Stiles of Redrock Acoustics.
These two men are truly remarkable at what they do. When
you hear Dickason say that “they may be the world’s
best driver designers” you know you have something.
Working exclusively with the world’s largest driver
manufacturer, Sonavox, Turnmire developed the world’s
standard in driver modeling software, SpeaD. Turnmire
and Stiles developed for Charles Grecco what they believe
is the world’s most advanced line of raw drivers.
Ranging from 4 inch midrange drivers to 15 inch woofers
and sub-woofers, these products not only meet the stringent
requirements for use in the pro audio industry but they
have also helped develop and incorporated the most sophisticated
real-time sensing devices which will continually monitor
the temperature of the coil and its excursion in future
designs. The four-inch mid bass driver used in the line
array was tested with pink noise at 200 watts for 8 hours
of continuous use with a compression loss of only 2dB.
This is a result of the cooling provided by their mMag
technology is licensed exclusively in pro audio by Charles
Grecco.
Ribbon Tweeter:
The use of planar magnetic drivers for pro sound provides a
remarkable clarity and detail that is simply not possible with
compression drivers and horns. The large radiating surface
area and extremely low moving mass of the tensioned film diaphragm
provides unparalleled speed and openness.
Planar magnetic drivers; sometimes referred to as ribbon speakers,
have long been regarded as the best high frequency devices
available. Additionally, they have also had a reputation for
being fragile and inefficient. Currently, with the availability
of neodymium iron boron magnetic material and significant advances
in the materials science related to the construction of etched
foil clad polymer film, today's planar magnetic drivers are
as efficient and handle several times the power of even the
best compression drivers with a fraction of the distortion.
The sensitivity of the 11.5" driver designed for Charles
Grecco is 105 dB@1w/1m, and is capable of handling 3600 watt
peaks for 200 ms. The output is fed into a manifold wave guide
to create a radiating source width of 0.75", resulting
in a remarkably wide, (110 degree) and even horizontal radiating
pattern. High frequency extension is well beyond 20kHz.
The subjective experience when listening to these systems is
that of hearing the best audio reproduction available anywhere,
including the highest priced, most sophisticated consumer loudspeaker
systems. That fact that this design when used in tandem in
the Charles Grecco line array can effortlessly attain the SPL
levels required for live sound in even the largest venues is
a monumental technical achievement.
David Graebener
Ribbon Designer
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BMS
4595 COAX Compression driver:
FEATURES :
| • |
Extended Bandwidth
(300 - 22000 Hz) |
| • |
Neodymium Magnet
Assembly |
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With two Subsystems
in one, each Driver covers a smaller Frequency range
for increased Power Handling, high Dynamic and extremely
low Distortion |
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Excellent Phase Coherence |
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Perfect Time Alignment
without Problems of Multi-Source Interference |
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Ultra light Weight
and small Size |
The 4595ND is a 1,5" coaxial compression
driver delivering a real coherent single point wave front
without hot spots with excellent phase coherence and perfect
time alignment. The driver is in fact a 2-way system employing
two concentric annular ring diaphragms. Each driver covers
a smaller frequency range for increased power handling, high
dynamic and extremely low distortion.
The larger of the two reproduces middle frequency
from 300 Hz upward, crossing over 6,3 kHz to the HF transducer
which is capable of reaching 22 kHz. The large diaphragm excursion
of max. + / - 0,8 mm results in high output and increased power
handling up to 1300 W peak. The voice coils may be driven in
conjunction with a passive crossover or driven individually
from an active crossover. The outer casting features extensive
heatsinking ensuring high power handling and low compression.
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Horns:
Constant Directivity Horns
All of the horns
in our product line have been exclusively design by Mr. Charlie
Hughes. You will find several articles in Live Sound Magazine,
as well as Syn-Aud-Con white papers. He is also a member
of the EASE and EASERA Developers Group.
The main design criteria
we set out when developing this line of horns was precise
pattern control, as well as exceptional sound quality. Mr.
Hughes has not disappointed. These horns are the most accurate
and musical horns I have ever offered.
There are four standard
horn patterns for the Installation Series and the Wedge Trap
Series. They are: 60X45, 60X60, 90X45, and 90X60. The front
fills have a 120 degree Slot horn, (pictured) as well as
45X90 and 45X60. As needed, we can add specific horn patterns
to suit your customers’ needs.
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Cabinet Designs and Testing:
The boxes are manufactured in Nashville TN, using the latest in
automated machinery. We use 13 ply Baltic Birch. Once coated with
truck bed liner, the cabinets are sent to another facility in
Nashville for component loading and final assembly. All products
are acoustically tested before leaving the facility. All EASE
data is independently provided by NWAA labs (http://nwaalabs.ipower.com/).
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