H SERIES

There's no doubt that sound quality is the most important criterion for any power amplifier intended for professional use. Power efficiency runs a close second - particularly in large systems. The new Yamaha H7000, H5000, and H3000 power amplifiers offer high power and outstanding sound quality in compact 2U rack-mount units with unprecedented efficiency. Efficiency that is so high, in fact, that mains power requirements are dramatically reduced while operational reliability is significantly enhanced. Other important features include MediaLink™ computer network compatibility, a choice of output modes, comprehensive protection circuitry, variable-speed forced air cooling, and more. The Yamaha H-series power amplifiers represent a major breakthrough in power amplifier efficiency and overall performance.

In spite of their compact 2U rack-mount dimensions, the H-series power amplifiers provide remarkably high power. The H7000, H5000 and H3000 deliver 750, 500, and 350 watts per channel into 8-ohm loads, respectively - an excellent selection for all professional sound reinforcement applications.

The real advantage, however, lies in the fact that the H-series amps are approximately twice as efficient as conventional types. This means that for the same power output you only need half the power normally required from the AC supply. Large-scale systems and networks of amplifiers can be used with much less chance of overloading the mains power supply, and the amps themselves run cooler for significantly improved reliability. This type of out-standing efficiency has been achieved through the development of totally new Yamaha 12184 PCT EEEngine technology which easily outperforms other efficiency-enhancing schemes; including drive voltage switching, pulse-width modulation, and switching series regulators. The Yamaha HED system provides a major efficiency boost without the need for complex switching circuits and without the sound degradation incurred by the use of previous systems.

In addition to aiming for the best possible sound quality through careful component selection, circuit design, layout, and construction, the same technology that gives the H-series power amplifiers unmatched efficiency also affords a distinct sonic advantage. An amplifier's ability to respond accurately to fast high-level transients is a vital factor affecting reproduction precision - in this area the H-series amps excel. They respond instantaneously to transients of virtually any magnitude without distortion, for extraordinary crisp, punchy sound - particularly in the bass region.

Operated in the normal stereo mode the H-series amplifiers deliver the high power levels listed earlier - 750, 500 and 350 watts. All three models can also be used in the bridged mono mode for extra high power: The H7000 pumps out1900 watts, the H5000 1400 watts, and the H3000 900 watts, all into 4-ohm loads. The H-series power amplifiers provide an extra margin of flexibility with a dual mono mode, which allows a single input signal to drive two independent speaker systems. In the dual mono mode the power rating for each speaker system is the same as in the stereo mode.

15-pin MONITOR/REMOTE terminals on the rear panels of all three H-series models provide direct compatibility with MediaLink™ protocol networks for state-of-the-art computer based system control and monitoring - an important advantage in large systems with many amplifiers in remote locations. The H-series amplifiers allow power and channel mute control as well as status monitoring of per-relay output level, clipping, output on/off, and heat sink temperature. Level control is also possible with the addition of an optional circuit board.

The H-series power amplifiers include a comprehensive power protection system designed to prevent accidental damage to the amplifier and any connected speakers. Power-on muting isolates the speaker outputs for several seconds after the power is turned on. This prevents the power-on voltage surge from reaching the speakers and allows the amplifier circuitry to stabilize before operation begins. DC sensing circuitry shuts off the outputs if a DC voltage greater than +/- 2 volts is detected at the output terminals. Thermal protection shuts down the system if the heat sink temperature exceeds 90 degrees C, and a power limiter reduces power output if a short or other fault results in a speaker load of less than 1 ohm. Protection, clip/limit, and thermal LEDs indicate the type of fault that has occurred, so the problem can be located and rectified quickly. Although protection circuitry may never be needed, it will save valuable maintenance and operation time if a problem does occur.

Although the H-series amps run cooler than other power amplifiers at comparable power output, they feature a comprehensive cooling system for optimum reliability and safety. Dual variable-speed fans automatically maintain internal temperatures within a safe operating range.

The input attenuators provided on the H-series power amplifiers feature precisely calibrated detents and smooth, noise-free control. This configuration allows accurate, repeatable level settings while providing perfect level matching between channels set to the same attenuation.

For compatibility with the widest possible range of equipment and installations, both balanced XLR and balanced phone jack input terminals are provided. Heavy-duty binding-post type terminals ensure solid, reliable speaker connections.

This thoughtful feature lets you lift pin 1 of the XLR-type connectors from the ground to interrupt ground loops when they occur, achieving quiet, hum-free operation.