# Onkyo TX-NR5008 questions



## THX-UltraII (Nov 19, 2008)

Just bought the TX-NR5008 and have some questions about it:

1. THX Ultra II subwoofer setting: I can select YES or NO there. Do you really only must select YES here when you own a certified THX-Ultra subwoofer? Or does this feature is not more then to enable Boundary Gain Compensation?

2. I ran the XT32 setup at 8 mic. places. After this the Onkyo calculates for a few minutes and then comes with a report of fronts rears and center of 40Hz. What does this mean? Does this mean that all frequencies from 40-20000Hz are played by my fronts, center and rears? If so, I thought it was best to have speakers on 80Hz always and let the subwoofer do 0-80Hz.
And it seems that the XT32 only did this and no more. The distance of the speakers is still on the values I picked before the XT32 measurement. (I ran a manual setup BEFORE the auto Audessey setup to see what Audessey would change but the distances remained the exact same values).

thxz!


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## Jungle Jack (Jul 28, 2009)

THX-UltraII said:


> Just bought the TX-NR5008 and have some questions about it:
> 
> 1. THX Ultra II subwoofer setting: I can select YES or NO there. Do you really only must select YES here when you own a certified THX-Ultra subwoofer? Or does this feature is not more then to enable Boundary Gain Compensation?
> 
> ...


Hello,
1) To the best of my knowledge, the THX Subwoofer Setting is indeed to enable BGC. I have tried it both off and on and have never noticed a huge difference. I would try each and whichever the Bass sounds best, is the one I would use.
2) Audyssey MultEQ XT Measures where it thinks the Speakers in your System will play cleanly down to, but I always change it to 80hz on all of my Speakers even though Audyssey sets them much lower. However, when set to 40, you are correct.

3) The Measurement has always been quite close to me when ran. Could it be you did a good job setting up the distances?
Cheers,
JJ

4) I would change the LPF of LFE to 120hz from the Default 80hz.


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## eugovector (Sep 4, 2006)

Info direct from Audyssey on setting crossover frequency: http://ask.audyssey.com/entries/108049-crossover-frequency

Short version, AVR manufacturers control how crossovers are set, not audyssey. With non xt32, setting xover to 80HZ allows the low frequencies to be corrected by the higher resolution sub filters. With XT32, number of filters in sub/sats are equal, so the same resolution of correction will happen regardless of where the crossovers are set. Still, a quality sub will typically outperform full-range speakers in the sub 80hz range bassed simply on the fact that that's what they were designed to do. A sub's one and only purpose is to reproduce those frequencies.

So, it's a matter of taste and speaker/sub placement can have a substantial effect as well, but most signs point to 80hz being the ideal crossover point. I'd raise the setting to 80hz.


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## Dwight Angus (Dec 17, 2007)

As per JJ's note Just set your xo's to 80 hz. When you adjust xo's always adjusted upwards never downwards as Audssey will not have resolution filters in place to acccommodate. So for example if the suggested xt32 setting is 40 hz you can adjusted upwards to 80 hz but not done to say 30 hz


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## eyecatcher127 (May 9, 2006)

I think it is there so you can turn the compensation on or off, but I've noticed that Saying "YES" and leaving Boundry compensation "OFF" appears to effect the sound also. I notice more infrasonic bass I believe, although I can't seem to measure it. I've measured the Boundry Compensation and it defeintly curbs some of the standing waves on the lower end below 20 hz or so if you have a lot of room gain it could be useful. I've opted to leave it off the bass sounds tighter and cleaner. I think perhaps it maybe doing some THX adjustments instead of Audyssey. Also the perception of the rest of the frequency spectrum changes if I test with the the sub off. I also can't seem to measure that sucessfully.

I also notice DSD DAC Direct, seems to have an effect the sound also even though I'm not using Super Audio sources. 

Anyone else notice thse things? Maybe I'm crazy.

To answer your first question You'd have to try it in your room.I don't believe it's supposed to be used in the Yes and OFF setting although it may work for you in your room. I seem to notice more bass below 10hz with it in that setting. ON and Yes, may be where a its trying to correct a THX sub that is supposed to be flat and reach down to 20hz -db i believe. This is where it may be attempting to do something with sub response in that respect.

To answer the second questions, it indictes that Audyssey detects your speakers -3db point is 40hz, so that is the crossover for your fronts, center and rear. You can raise it but it is not recommened to lower since audyssey doesn't correct below what it detected as the -3db point. The LFE should be set to 120hz as per audyssey, this is crossover for digital .1 sources only otherwise output below front rear center will be sent to the subwoofer.


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