Crown Macro-Tech MA-2402 User manual

1
Celebrating the Crown
Macro-Tech Series
Your Macro-Tech®Signature Series amplifier is the
culmination of a long heritage of Crown®products
and design ideas that began in the early 1970s.
In these pages you can explore how the Macro-Tech Series came to be, understand its advanced features, and enjoy stories and sales literature from its colorful past.

2
Sometimes a product fits an application so well, it
is deemed a classic. The term is synonymous with the Crown®Macro-Tech Series of power amplifiers.
That product line, and its predecessor Micro-Tech®, sparked
innovative technologies that provided lower distortion, less thermal stress, higher output power, greater reliability, more power density and superior audio quality. No compromises, no gimmicks. Just brilliant engineering backed by superior manufacturing, support and an unsurpassed commitment to quality. Like all Crown amps, the defining characteristic of the Macro- Tech Series is sonic accuracy. A tight, rock-solid low end, with smooth, detailed highs and a well-defined midrange. In short,
Crown Macro-Tech Series
Enjoy!
the most accurate reproduction of an audio signal you’ve ever heard. And because we put the quality of sound above all else, Crown amplifiers are the most coveted in the business. When it comes to manufacturing amps, our work is based on one simple fact: there are no shortcuts to quality. And our Macro- Techs have proven this time and time again in some of the most demanding applications in the world. For this special, limited Macro-Tech release, we wanted to bring you more than just the typical operation manual. This brochure goes much further, delving into the Macro-Tech’s development, design philosophy, and advanced technical features. We’ve also included some brochures from the past, a bio of Crown’s chief R&D engineer Gerald Stanley, customer statistics, anecdotes and more.
Since 1984, Crown has shipped approximately 272,625 MT and MA amplifiers to date. That’s approximately 54 million watts into 4 ohms or 65 million watts into 2 ohms!

3
Crown Macro-Tech amplifiers were used at the 64,640-seat Sangam Stadium in Seoul, South Korea, during the 2002 World Cup.

4
A Sampling of Crown Macro-Tech Users
THEME PARK Universal Studios Everland (Korea) Six Flags of America FIXED INSTALL Club Capitale Sydney 2000 Olympics Crystal Cathedral Official All Star Cafe Hard Rock Live Experience Music Project Spirit, Roxy Deep night clubs
TOUR Neil Diamond tour Pro Show, SPL Sound, XFL Seoul Word Cup 2002 Audio Analysts Morgan Sound Clair Brothers Disturbed (band) Art Garfunkel Tour Maryland Sound Gemini Sound On Stage Audio Enterprise Live
STADIUM / ARENA American Airlines Arena American Airlines Center Ralph Engelstad Arena Key Arena Xcel Energy Arena Conseco Field House Coors Field Volkswagen Stadium Hong Kong Stadium Racks of Crown Macro-Tech amplifiers power this 2001 extravaganza staged in Salt Lake City’s Salt Palace for the Annual Gala held by Utah Governor Mike Leavitt. Rocky Mountain Audio Visual chose Crown Macro-Tech along with JBL Vertec speakers to provide concert-quality sound for the event. (Find out more at http://www.jblpro.com/pressroom/rmav_utah.htm.)

5
Crown Macro-Tech amplifiers power the premium sound system employing JBL PD Series speakers in the 400,000 sq. ft. Ralph Engelstad Arena in Grand Forks, North Dakota.

6
The Macro-Tech Design Philosophy
The Macro-Tech product line, and its precursor
Micro-Tech®, awed the audio industry with new
technologies that reduced distortion and thermal
stress — while increasing reliability, audio quality, power density and power output. Three patented technologies invented by Crown’s Gerald Stanley led to those benefits: •Grounded Bridge™topology provided 4 times the power of
existing power transistors without sacrificing reliability.
•Junction Temperature Simulation (JTS), otherwise known
as Output Device Emulator Protection (ODEP®), protected
the power transistors from overheating and maximized their potential power output by keeping them at the optimum temperature.
•Variable Impedance or VZ®power supply, also called bi-level
power-supply switching, was used in the MA-3600VZ and MA- 5000VZ Series. The supply changes its impedance to adapt to the signal voltage and current. This technology permits large amounts of power in a compact package while achieving ultra- low distortion and without generating excess heat.
How It All Began... The brainstorming for this whole family began with collaboration between engineers Gerald Stanley and Jim Wordinger. In considering the drawbacks of current power amplifiers, they were looking for ways to: •pack more power into a smaller rack space •improve reliability by preventing overheating •lower the cost per watt. Gerald’s Grounded-Bridge design and Junction Temperature Simulation were already in his toolkit. In 1975, JTS was employed in the SA-2 and PSA-2 amplifiers, while Grounded Bridge was used in the M-600. Gerald and Jim thought, “How about taking our two best technologies and putting them in the same product?” The Micro-Tech Series was born. The original name of this series was to be HVA for High Value Amplifier.
How about
taking our
two best
technologies
and putting
them in the
same product?”

7
In those days, Crown was recognized as a manufacturer of home hi-fi products. But the HVA Series was intended for pro audio Touring and MI, not for the living room. It was a new direction for Crown. Crown’s president at that time, Max Scholfield, recognized that Crown’s marketing needed to be shaken up, so he hired Dr. Clay Barclay to drive change in Crown’s marketing and sales divisions. Clay realized that the MI and Touring industries needed a product like this, and he sold the idea to Crown and to potential customers.
A 1983 schematic by Gerald Stanley of the Grounded Bridge circuit.

8
Micro-Tech Jim and Clay used to share ideas over lunch, where Jim told Clay about the concept. Clay came up with the name “Micro-Tech” because the goal was to put high technology into a micro-sized amp. It was a new packaging paradigm as well as a new market. In the early 1980s, Jim Wordinger went to Showco, one of the major touring sound companies. At that time they were doing sound for David Bowie using PSA power amps. According to Jim, “We asked them what they would like to see in an amplifier.” “They said, ‘We’d like them smaller and lower-cost.’ I couldn’t say anything about what we were working on, but their comment certainly vindicated our design goals. Showco was one of our first customers; they used a lot of Micro-Techs. We had a relationship with them. They would find any problems first and then we’d fix them.” Eventually Clair Brothers bought Showco. Now they are using over 2000 MA-3600VZs.
The MT-700 (never released) was the first Micro-Tech amp. Then came the MT-1000 which provided 1000 watts into 2 ohms. Next was the MT-1200 which produced 1200 watts, thanks to bigger power transformers. The technology in Micro-Tech products helped Crown develop amps for Magnetic Resonance Imaging (MRI). General Electric asked Crown to make amplifiers with more voltage and current than what was available. We created bigger amps for GE, such as the 7780, using JTS and Grounded Bridge.
An early sketch by Jim Wordinger showing a proposed chassis layout of a pre-Micro-Tech power amplifier.