# Crossover frequencys / LFE cutoff



## joshr (Dec 9, 2011)

Hello all-

Im working on setting up my Onkyo HT-RC360 and I have a question about how to set the crossover for the subwoofer.

In the speaker configuration menu of the reciever I have options for setting the crossover on all my speakers. For the center fronts and surround speakers, I think I understand the setting. When I pick a crossover frequency, sounds below that frequency will not be sent to that speaker. For example, my center speaker is a JBL CL505, which says it has a frequency response from 70hz to 20khz. So I set the crossover at 70, and the reciever doesnt send sounds below 70hz to that speaker. Im 99% sure that's correct, but someone please correct me if Im mistaken.

The setting for the sub is where I have my question. In the manual it calls this setting the "cutoff frequency" instead of the "crossover frequency" Is this the oposite? Does it mean that sounds above this frequency will not be sent to the sub? The sub Im using is a Polk PSW-110, which has a listed frequency response of 32hz-250hz. The options I have in the reciever for this setting are between 80hz and 120hz. My guess is that I set it to 120hz and this tells the reciever not to send the sub frequencies above 120hz. But do I have this backwards? Does this setting tell the reciever not to send the sub frequencies below 120hz the same way it does with the other speakers? Should I have it set to 80hz instead to get the most range out of the sub?

Part of me feels that this is a simple question with a simple answer and that 120 is the correct setting, and I'm just overthinking it. But Id love some advice from more experianced people.

Thanks for your help

-josh


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## ironglen (Mar 4, 2009)

The answer to your first question is correct, set it to 80hz and the signal will trail off at 80hz, basically preventing < 80hz material from your speaker.

If you set all your speakers to 80hz, then go ahead and set your sub to 80hz, you'll be 'crossing over' signals to either the speakers or sub at the same point, thereby producing all the material without a gap or loss in frequency.

Perhaps you had more capable mains in the future (60-20khz), then you could set the front speakers (mains and center) say to 60hz and surrounds to 80hz (because they're less capable than your mains), and then you might set your sub to either 60, 70, or 80 hz depending on preference/sound quality/power handling capability.

Hope that helps.


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## Kal Rubinson (Aug 3, 2006)

joshr said:


> Hello all-
> 
> Im working on setting up my Onkyo HT-RC360 and I have a question about how to set the crossover for the subwoofer.
> 
> ...


Your plan is good. Set the main channel speakers to 80Hz (a bit above their rated low end). This will send signals above that to the main speakers and reroute the signals below to the sub. The setting for the sub does not affect this at all. It is a setting for the separate LFE channel that is used by many sources and a setting of 120Hz for the sub will permit all of that to pass to it (along with the under 80Hz bass rerouted from the other channels).


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## joshr (Dec 9, 2011)

Thanks for your replies.
I think I made my original question more complex then it has to be, let me rephase it:

If I set my "LFE cutoff frequency" to 120hz this means that the reciever will send sounds BELOW 120hz to the sub. From 0hz (in theory) up to 120hz. Correct?

I have some other questions concerning some of the things I read in the replies, but I'll save them up for a new thread....

Thanks for your help

-Josh


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## natescriven (Jan 12, 2011)

I think you've said it the right way. Kal's explanation makes the most sense. It agrees with what I've read in other posts as well. Set the LFE @ 120 and crossover @ 80 or whatever you're using


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