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Is it normal for a pair of speakers to have and 1.5dB average sensitivity difference?

EB1000

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Hi

I just bought a second pair of Aria 906 for a bedroom setup (ordered the MiniDSP SHD, the NAD C658 will be reassigned for the bedroom).

I measured the old pair using REW and the difference was 0.5dB, matching the YPAO calibration results. I even tried a nearfield measurement, and the average S{L difference was 0.5dB.

I did the same with the new pair, but this time I got an average of 1.5dB. Even audyssey results had one speaker at -2.5dB and the other at -0.5dB. I tried swapping left and right location and repeating the calibration, and the results had swapped as well, indicating that one speaker is more sensitive that its twin by 1.5dB. REW images using 1/1 and 1/6 smoothing are attached.

Is this normal, acceptable variation or is one speaker damaged? The both sound exactly the same after level marching. I need to know if I should ship them back and ask for a replacement. I've contacted Focal but it may take time for them to answer if they even will.

Thanks
ARIA.jpg
 

Sancus

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Not sure about Focal's standards for pair matching, but that seems like a problem to me. 1-2dB tweeter variation is common, but to have such a large and consistent midrange deviation is strange for a speaker that costs that much.
 

abdo123

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the difference is too consistent to be a quality control thing, perhaps the mismatch is electronic?

either way, since it's so consistent, just boost one channel electronically.
 
OP
EB1000

EB1000

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Thanks. I'll repeat a true near filed REW swap tomorrow. It could be cable related (its not amp related because I did swap the amps). I did not test the interconnects (pre amp to power) nor the speakers cables, because both are high quality (got them from Ghent). I will test those as well. Is it unlikely to have a consistent mismatch across the entire frequency range, unless on speaker has a wiring issue on its input.
 
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EB1000

EB1000

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OK, after doing more tests. the speakers are fine. 1.5dB level difference is originated from the NAD C658. It's even present on the headphones out... I'm not very surprised after all I've been through with this lemon... Anyways, Dirac live correction compensates for the difference.
 

MZKM

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OK, after doing more tests. the speakers are fine. 1.5dB level difference is originated from the NAD C658. It's even present on the headphones out... I'm not very surprised after all I've been through with this lemon... Anyways, Dirac live correction compensates for the difference.
Wait, you stated you swapped positions. Did you keep them plugged into the same speaker outputs on the amp?
 

AdamG

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I was going to say, unless you have pristine perfect hearing, most humans may have a similar or larger disparity in their ear to ear hearing ability anyway. I know I do, but I don’t think my hearing is typical.
 
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EB1000

EB1000

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Wait, you stated you swapped positions. Did you keep them plugged into the same speaker outputs on the amp?

I did the first test very late at night at low volume using REW. I must have swapped both speakers and connectors or ran REW at low volume. Today I repeated the test on my second system and both speakers registered similar results. Then I tested the C658 with different pair of speakers and headphones. Left channel is 1.5dB higher that right channel. I wonder if this is a bad component or internal miss calibration. I can try contacting NAD support which will be my 20th support ticked since getting the damn thing...
 
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