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Question about "fixing" a potentially non-ideal d'appolito arrangement

Vladimir Filevski

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Lay the speaker horizontally and put it on something to raise the tweeter at half of the room height and do the measurements again ("horizontal" off-axis would turn to be vertical). What is the microphone to speaker distance? It should be at lest 1 meter, preferably 2 meters.
Every non-coaxial loudspeaker have issues with vertical off-axis frequency response.
(Edited.)
 
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anphex

anphex

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The tweeter was already at center point in my room due to my low ceiling. For the rest have a look at the measurements I attached.

But here's a new twist to the story, which made me think I'm stupid.
Since the BMR have asymmetrical mounting plates I could just turn the BMR 90° and move them closer to the tweeter. This reduced their distance from each other from 24cm to 21,5cm which is a great improvement for free. The theoretical crossover frequency just got risen from 1450hz to almost 1600 hz, which reduces the gap until 2000hz (tweeter crossover) hz by a nice margin. The only drawback that I may have altered the baffle correction but at least THIS is fixable by EQ. Dispersion is not.
 

Vladimir Filevski

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Low ceiling is the most limiting factor in quasi-anechoic loudspeaker measuring in-room. Laying speaker horizontally for measuring will bring both BMR drivers at the half height of the room, improving quality of off-axis measurements.
Turning 90 degrees of both BMRs is interesting idea worth of trying - it may (or may not) bring better off-axis response at BMR-tweeter crossover frequency, but monitor what happens with off-axis response at low-mid driver - BMR crossover frequency.
 
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