Multichannel 5.0 / 5.1 Bass Management / Crossover with Procedural EQ

Per this 2019 post it appears multichannel bass management using procedural EQ is achievable for 5.1 but not 5.0 files. Does anyone know if this is still the case?

I was playing around with a precedural EQ (with additional headroom management) - mix all channels to themselves, mix all channels to LFE, high pass filter for all non-LFE channels at 100Hz, low pass filter for LFE at 100Hz (both 24dB/octave) - and I was getting a significant amount more bass from the subwoofer than when just using my Marantz SR7013 100Hz crossover setting. It did not occur to me that a channel mismatch could be occuring (I will try 5.1 and 2.1 files tonight to rule this out). Is there something else with the crossover setting I should be addressing that might be causing such a noticeable bass boost?

You get that increase if you sum all the channels into the LFE and may even overload the signal path. If you are summing 5 main channel bass, you should sum them as .20x each although you still may have to tweak the LFE up a bit anyway.

Would this be a negative Gain (dB) adjustment for each channel mixed to LFE?

… should be -6dB

EDIT:
Sorry, wrong, since you’re summing 5 channels into one, as Kal rightly said, of course.
So it’s -14dB for each


(taken from http://www.sengpielaudio.com/calculator-db.htm)

Post script:
How come, you didn’t get massive digital clipping noise?

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Possibly because I was testing with a classical track with not too much dB under 100Hz - the double basses from the opening fanfare of Bruckner 9 gave away that something was amiss. Guess I’m lucky I didn’t test something with a bass drum!

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I’ve not had any luck getting 5.0 files to not drop off one rear channel when using this procedural EQ (I’m using HDMI out from a Linux-based Roon endpoint to my AVR). Is there any way to overcome this, and is this issue only for HDMI out setups? Or does Roon also have Mix issues mapping 5.0 to multichannel USB DACs like the Okto Dac8 pro and the recently-released Topping DM7?

Maybe you need to adjust your 5.0 to output as 7.1, as I have in my main system. I have an Okto dac8pro. I don’t recall on this track but with 4.0 files, I had to create a silent fifth channel to get Roon to properly send to the correct speakers. Music Media Helper has an utility to do this. JCR

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