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1. IMPORTANT NOTICE
We appreciate your reliance on us when you purchased our fourth generation SPM
(Switching Power Mosfet) PAM amplifier.
In order to obtain the maximum performance and perfect operation, it is VERY
IMPORTANT that you carefully read this manual.
Finally, let us recommend you our T echnical Services whenever the amplifier should be
repaired.
1.1. Precautions
The amplifiers, specially the high power models, have a high power consumption and so,
special care must be taken when sizing the mains wiring. We recommend a 2.5mm
2
(or bigger)
section for the PAM300/600/1000/1400 models and 4mm
2
section for the PAM2000/2600 models;
also use magneto-thermal switches of minimum 10A for the former models and 15A for the latter.
This values are for one amplifier and 220Vac; double the values if the amplifier operates at
110Vac.
The amplifier must be linked to a proper earth connection wich must also be isolated from
the machines not related to the audio chain (Earth resistance Rg=30
Ω
or lower).
The environment must be dry and dustless.
WARNING!: Always disconnect the amplifier from the mains supply before handling
and/or connecting or disconnecting it. Never connect the loudspeakers while the
amplifier is on; remember that voltages as high as 400Vpp and up to 150A currents can be present
at the output. There are no user or serviceable parts inside the amplifier.
WARNING!: Due to their internal sructucture, the four output poles are active and
not referred to ground, the PAM2000/2600 models cannot be used in 'bridge' mode. Do
not connect any of the output poles to ground.
2. INTRODUCTION
The PAM amplifiers have been designed to fulfil the audio professional requirements of a
strong and reliable power amplifier. ECLER introduces a new concept in the professional audio
with this amplifiers: the use of switching field effect transistors. The SPM (Switching Power Mosfet)
technology has been developped and patented by ECLER-Laboratorio de Electroacústica S.A.
This components were only used in switching applications until today and their use in the audio
field means a firm and spectacular progress in relation to the conventional systems.
This advantatges can be summarised as follows:
a) The internal resistance is lower for the switchin g mosfets than for the bipolar transistors,
meaning that the amplifier will operate colder and with strong and well controlled bass.
The conventional audio mosfets have an internal resistance 4 to 7 times greater than the
switching mosfets.
b) The fast operation of the mosfets gives both a treble transparency only achieved by the
valve amplifiers and a very low TIM (Transient Intermodulation Distortion).
