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freeDSP / freeDSP-aurora

freeDSP ADAU1452 with 8 analog input, 8 analog outputs, S/P-DIF I/O, ADAT I/O, USB Audio Class2, WiFi, Bluetooth
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Suggestion: move crossover to the beginning of the signal processing chain in HomeCinema71 plugin #76

Open cborss opened 3 years ago

cborss commented 3 years ago

According to the documentation, the crossover / bass management summation is located after the parametric filters in the HomeCinema71 plugin. I suggest to move this block to the very beginning of the signal processing chain.

This plugin is well suited for implementing the bass management and room / loudspeaker equalization of a typical A/V receiver. In this use case, the parametric filters are used to calibrate the HiFi system according to the loudpeaker characteristics and their interaction with the room (wall/floor/ceiling reflections and room modes). If the bass management block is placed after the parametric filters, then these filters no longer only affect the loudspeaker that shall be equalized but also the subwoofer. Consequently, the loudspeakers cannot be equalized independently. And even worse, the signals that are mixed together with the LFE into the subwoofer channel have no longer the same phase relation as the original mix.

deadsnare commented 2 months ago

I also noticed that oversight since I have the exact same usecase. I have managed to create two plugins, one for 7.1 and one for 5.3 systems, which put the crossovers at before the satellite and sub PEQs. The plugins also allow for separate House Curve EQ and LFE gain management (in case your equipment does not add the required 10 dB gain). Have a look at https://github.com/deadsnare/freeDSP-aurora-bass-managed-surround. The readme needs some work, but the plugins are fully functional.