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Simulation Overview of the 'Double Bass Array' Configuration.

kemmler3D

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That's the third method I tried. Summary of the three curves:

1. Control curve. No changes to the DSP.
2. Right sub phase shifted according to the formula.
3. Left sub delayed with respect to the right sub. The delay was obtained by placing the mic at the tip of the red arrow and measuring the arrival of both sub peaks. I then time aligned the left to the right sub with respect to the microphone position, which "should" give me a wavefront heading into the dining room.

I can't remember which curve is which, but that is academic now because all 3 are exactly alike.
Oh, I see, sorry. I think what you would actually need to do is have the wavefront cancel the next incoming wavefront at the entrance to the dining room. But you can only do this for certain frequencies at any given time... if it works at all...

Solution: Put some subs in the dining room! Easy! ;)
 

Keith_W

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Oh, I see, sorry. I think what you would actually need to do is have the wavefront cancel the next incoming wavefront at the entrance to the dining room. But you can only do this for certain frequencies at any given time... if it works at all...

Solution: Put some subs in the dining room! Easy! ;)

The whole point was to get rid of excess bass and dump it somewhere I don't care about, like the dining room :p

How did it measure at the MLP though?

I can't remember. I don't think I have those measurements any more.
 

DonH56

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You cannot really direct the sound when wavelengths are so long and room modes dominate the response. More than just steering is involved, you need active drivers to cancel the undesired components. That is part of what I decided after piddling with it on my own many years ago. Steering a radar beam with a fairly small dish works well when the carrier is 10~40 GHz or more. In a room, with wavelengths of many feet and local room modes (vs. free space) dominating the bass response, simple steering did not work for me (or apparently for you). At one point I played with my subs (four, near the four corners of the room) to try to implement a phased array approach, but aligning everything was very tricky and my DSP-fu is not that strong. I had a scheme using six subs that might have worked, placing two more at the sides to help cancel modes, but did not have room for them (physically), had other bills eating any spare funds, and interest waned.
 
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