Emperor DSP-X Digital Electronic Crossover
The Emperor DSP-X digital active crossover is designed to be used with the top five models in the German Physiks loudspeaker range to allow them to be operated in fully active systems
This provides a significant improvement in performance over a passive system, with the additional benefit that the crossover characteristics may be fine-tuned using a remote-control application. The unit may also be programmed to work with almost any other 2-way or 3-way loudspeakers. It uses high quality analogue input and output circuitry and a precision digital processing section to provide exceptional sound quality.
It is supplied as standard with our Gaudi, Emperor and Loreley models and may be specified as an optional extra for our PQS-302 and PQS-402 models.
What is the difference between an active and passive system?
Passive System
Most loudspeakers use two or more drivers to cover the full audio range. In the case of a 3-way loudspeaker, one driver will cover the low frequencies, one the mid-frequencies and one the high frequencies. Each driver will be optimised for the range it covers. If it is operated outside of this range, it will produce high levels of distortion and possibly result in the driver being damaged.
A filter built in to the loudspeaker cabinet called a crossover, takes the signal from the power amplifier and splits it into frequency bands appropriate for each driver. The crossover uses inductors, capacitors and resistors, which are referred to as passive i.e. non-amplifying components and so this type of crossover is called a passive crossover. Figure 1 shows an example of a system with a 3-way loudspeaker using a passive crossover. Such a system can be comparatively simple, requiring only one power amplifier for each loudspeaker.
Active System
In an active system, the passive crossover is omitted and a power amplifier is connected directly to each section of the loudspeaker. The signal to drive each power amplifier is provided by the active crossover, which takes its signal from the preamplifier and then filters it into the appropriate bands. Figure 2 shows an example of how the Emperor DSP-X digital crossover would be used to implement a fully active 3-way loudspeaker system.
The filters in an active crossover may be totally analogue, or they may be digital. The Emperor DSP-X uses digital filters, as they allow more sophisticated filter characteristics to be implemented, enabling the loudspeaker designer to get much closer the exact filter characteristic that they wanted.