DSP and PlateAmp
Why DSP ?
Active crossover with DSP is advised for horn speakers: The energy in the horn is defined at the begining and as we want a constant directivity behavior the on-axis horn response will show a bell shaped response, as explained here in Horn & Energie.
It would be very hard to do a passive crossover for a high efficiency horn speaker.
DSP PlateAmp : The Hypex Fusion Amp
The Hypex Fusion Amp line-up are state of the art Class D + DSP :
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They have FIR capacities, powered by the Hypex Ncore MP family.
They have all possible inputs including AES/EBU and even a remote control for sources and volume so they act also as a pre-amp.
A passthrough allows adding a sub.
Mini DSP Flex HTx
The Flex HTx, and not the “HT”, is a 8ch IN (USB/HDMI/Analog) or 2ch IN (Toslink/SPDIF) to 8 channels OUT asymmetrical and symmetrical analog.
Powered by a SHARC CPU, the best one.
The capacity to accept multicanal on HDMI E-ARC input is very rare for a DSP and routing capacities allow it to easily add a sub.
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It need to be paired with amp, with symmetrical analog output.
Pro solution, the Xilica Solaro FR1
The FR1 is a DSP with extended card for almost everything except HMDI, he can be in network thanks to DANTE and manage until 64 channels.
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It need to be paired with block or pro amp, with symmetrical analog output.