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2. The Product
2.1 Product Description
The digital, multi-channel DSP amplifiers belonging to the DI-SERIES are equipped with FOHHN
AUDIO DSPs (digital signal processors). These DSPs contain (per amplifier channel) a programmable
EQ, Delay, X-Over and dynamic processor.
DI-SERIES DSP amplifiers are equipped as standard with four digital AES/EBU inputs and four Link
Outs. Digital inputs for Dante™ and Optocore networks, digital AES/EBU XLR inputs and analogue XLR
inputs are also optionally available. The standard outputs are terminal blocks designed for leads of
up to 6 mm² –the amplifiers are also optionally available with Speakon output connectors. All
amplifiers (regardless of the number of their output channels) always have four inputs with DSP input
processing –in other words: their four input channels can each be mixed in the DSP.
In addition, presets are stored that contain loudspeaker protection data and sound optimization data
for all FOHHN loudspeaker systems. These optimisations, together with multiband limiting, ensure
the best possible sound performance and operational safety. Custom created user presets can also
be stored.
Thanks to their integrated FOHHN AUDIO DSP, the amplifiers can be networked, remotely controlled
and remotely monitored. A single piece of control software, FOHHN AUDIO SOFT, provides access to
all DSP functions and presets. (The current version of this software can be downloaded free of
charge at: www.fohhn.com.)
At the heart of each amplifier is an in-house developed digital power supply that is significantly
responsible for the sound. It constantly analyses the supply voltage and processes this accordingly
(Power Factor Correction). The power supply enables the amplifier to deliver as much energy as
possible in the shortest possible time, thus enabling the full dynamic range to be reproduced over
the entire audible frequency spectrum during live music applications –while also turning the least
amount of energy into heat. The result is a significant increase in the available peak power over
several seconds. An integrated microprocessor equips the power supply with measuring, monitoring
and communications functionality. As a result, important factors such as temperature, supply voltage
and capacity can be monitored and controlled accordingly. In the event of mains overvoltage, the
amplifier will shut down.
The amplifier’s fans are temperature controlled and optimised for extremely quiet operation. The
fans are not used when the amplifier is in an idle state. The fan and filter foam can be manually
cleaned, without the need for tools.
An integrated Power-Up Delay enables sequential (remote) power-up of a number of connected
amplifiers within a rack. For larger installations and live sound applications involving multiple
systems, this function significantly eases the general handling.
The amplifiers are additionally equipped with two programmable switching contacts as well as a fault
contact for easy integration into building services.