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Is there a good technical description of Dirac Live

Jeromeof

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So, I understand the basics of Room correction (and EQ'ing a room) - and use Audyssey with my Denon (to pretty good effect when A/B testing it myself with it on and off). But with my limited understanding it seems like this type of Room correction is still really an averaged out change in given frequencies (typically lower bass ones) to compensate for the sound reflection off walls within the room. Nothing wrong with that but I am wondering does Dirac Live go further and how 'real-time' can Room correction get.

So for example I have a basic understanding of noise cancelling headphones - i.e. playing the inverse of the predicted noise back into the headphone to cancel out noise, i.e. analysing the previous say 100ms of background "noise" / isolating this from other sounds and playing the inverse back. I imagine the better noise cancelling headphones have better 'real-time' filtering / isolating DSP technology than cheaper ones (who are mostly just playing back the inverse of recorded background noise).

Anyway, what I was wondering was given that different frequencies travel at different distances and have different reflective properties, is there a 'real-time' Room correction technology which would work with a similar technique, use the previous 100ms (or whatever timeframe - frequency dependent ) to calculate in real-time the inverse of that signal bounced off the wall at and add that predicted reflection to current audio. As in my limited understanding that would I imagine give the best possible way to cancel out the audio "reflections" heard, record what was played, calculate what the reflection of that might be and when it likely to be heard in the future and inject the inverse into the current audio being played.

Please excuse my limited understanding, just curious about the technology.
 

Berwhale

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This maybe... https://www.dirac.com/wp-content/uploads/2021/09/On-equalization-filters.pdf

"In this note I discuss some issues in filter design for equalization of sound systems. The emphasis is on rationale, not on experiments, and I will focus on a few common misunderstandings. I will briefly describe the basic concepts used in sound equalization, such as FIR and IIR filters, minimum and linear phase and present basic mathematical facts as well as give a background to the philosophy behind the Dirac Live approach."
 
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