Lab.gruppen E 8:2 - Manual (Page 7)

5. Introduction
E SERIES Operation Manual rev 2.0.0
7
5.2.2. Amplifier sensitivity / gain
For ease of use in system integration, E Series have been designed with a fixed sensitivity of 4 dBu. Each model
offers two operational modes individually selectable per channel:
* “70 V” – Optimized for constant voltage systems but also can be used when load impedance is 8 ohms or higher.
Input signal of 4 dBu produces 70.7 Vrms output, for gain of 35.2 dB.
* “Lo-Z” – Optimized for driving loads with impedance below 16 ohms. Input signal of 4 dBu produces the rated
burst power into 4 ohms; gain varies by model.
5.2.3. Protection and performance optimization
Appropriate and reliable power amplification is vital to any audio system. Inadequate or faulty power amplifiers
could cause damage to loudspeakers, or in some cases to the power amplifiers themselves. To prevent damage
or service interruptions, E Series amplifiers offer advanced features to protect both internal circuits and connected
loads. These features include the mains current limiter that allows several amplifiers to be connected to a typical
mains outlet.
Standard E Series protection features include:
• A CPL (Current Peak Limiter) ensures that the amplifier’s output does not exceed the safe current handling
parameters of the amplifier components.
• Temperature protection ensures that the amplifier will not be damaged by exceeding thermal limits. A TEMP
indicator LED flashes when the amplifier approaches thermal limits to allow user action before protective muting
engages.
• A PAL (Power Average Limiter) limits the maximum average power consumption from the mains.
• DC protection ensures destructive DC signals will not appear at the amplifier outputs. If such conditions occur
an internal fuse opens.
Note! There is no open fuse indication on the amplifier. If a channel indicates signal presence but
there is no sound, an open fuse could be the cause. If an internal fuse is blown, then the amplifier
needs service.
• Under Voltage Limit - A temporarily low mains voltage will indirectly initiate limiting if a high output level
is attempted. In most circumstances, depending on signal characteristics and level, the amplifier will remain
operational. This limiting allows the amplifier to remain functional during sustained periods of lower mains
voltage, as well as during temporary dips and when very long mains cords are used.
• Low inrush current ensures that the mains breaker will not trip when several power amplifiers are turned on
simultaneously.