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Brent_S · 05-20-2008, 06:55 PM

Was the SPL meter's mic in the same spot and orientation as the Onkyo's measurement mic? The Onkyo mic, especially on a tripod, should be oriented straight up. On the other hand, the SPL meter on a tripod was likely faced forward to some degree. Your measurements suggest such a forward bias. The LF to C/RF difference could be a difference of 0.2dB if you're using a digital SPL...the difference between rounding up/down or a slightly closer placement to that side when the SPL meter was used.

According to one of the Audyssey principals, the Onkyo mics are pretty accurate at setting relative levels....speaker to speaker SPL. Their target is to adjust the trims to get 75dB from all speakers, but there is some variability in the mics' absolute sensivity. So, you could easily end up with 71dB, 74dB, or even 77dB at 0dB MV after calibration. I was fortunate that my measurement mic seemed to be dead on compared to my old analog SPL meter.

And finally, there's nothing wrong with adjusting the channel levels to taste. It doesn't effect the Audyssey room eq. I bumped both my sub and surround channels a dB or two.

-Brent

05-20-2008, 06:55 PM	#8 of 8
Brent_S Member Location: Wilmington, NC Join Date: Oct 2000 Local Time: 08:31 AM Local Date: 11-18-2008 Posts: 382	Re: Are these speaker settings right? Was the SPL meter's mic in the same spot and orientation as the Onkyo's measurement mic? The Onkyo mic, especially on a tripod, should be oriented straight up. On the other hand, the SPL meter on a tripod was likely faced forward to some degree. Your measurements suggest such a forward bias. The LF to C/RF difference could be a difference of 0.2dB if you're using a digital SPL...the difference between rounding up/down or a slightly closer placement to that side when the SPL meter was used. According to one of the Audyssey principals, the Onkyo mics are pretty accurate at setting relative levels....speaker to speaker SPL. Their target is to adjust the trims to get 75dB from all speakers, but there is some variability in the mics' absolute sensivity. So, you could easily end up with 71dB, 74dB, or even 77dB at 0dB MV after calibration. I was fortunate that my measurement mic seemed to be dead on compared to my old analog SPL meter. And finally, there's nothing wrong with adjusting the channel levels to taste. It doesn't effect the Audyssey room eq. I bumped both my sub and surround channels a dB or two. -Brent