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1. IMPORTANT REMARK
Congratulations! You are the owner of a carefully designed and manufactured
equipment. We thank you for having purchased our MPA4-150 / 4-400 power amplifier.
It is VERY IMPORTANT that you read this manual before connecting the amplifier in
order to obtain its maximum performance.
We recommend our authorised Technical Services whenever any maintenance task
should be needed so that optimum operation shall be achieved.
2. INTRODUCTION
This multichannel power amplifier has been designed using the same technology as
the PAM amplification series. With this technology, ECLER introduced a new concept to the
world of professional audio: The use of switching field effect transistors. The SPM-Technology
(Switching Power Mosfet) has been developed and patented by ECLER S.A. The use of these
parts for audio applications represents a firm and spectacular enhancement comparing to
conventional amplifiers.
These advantages can be outlined as follows:
a) Lower internal resistance than bipolar transistors, which leads to less heating of the
amplifier and more powerful and controllable bass.
Conventional Mosfets have a 4 to 7 times bigger internal resistance than switching
Mosfets.
b) The extremely high speed of these devices gives a transparency to the upper
frequencies till now only achieved by tube amplifiers. This fact also reduces TIM (transitory
intermodulation) to very low levels.
The MPA4-150 / 4-400 amplifier station consists of four 147W/4
Ω
/ 410W/4
Ω
amplifiers which can be configured through a set of switches found on the rear panel. This
allows multiple amplification setups useful in many situations, for example:
Four mono amplifiers for four different mono inputs
When setup this way, the MPA4-150 is able to amplify four different audio signals, each one
having a dedicated volume control.
Four mono amplifiers for one common mono input
The amplifier operates now with just one input signal for all amplifiers, but preserves the ability to
control each channels volume independently. This setup is useful when distributing signals to
different zones.
Four mono amplifiers for one common stereo input
This setup is similar to the previous example but the input is now a stereo signal. The amplifier
adds both stereo channels together converting them into a mono signal.
Two stereo amplifiers for two different stereo inputs
Each stereo channel offers a dedicated volume control. Useful for addressing two zones with
two different stereo signals.
Two stereo amplifiers for one common stereo input
This setup is similar to the previous example but the input is now a single stereo signal which is
fed to both amplifiers.
Summary of Contents for MPA4-150
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