# Crossover setting for fronts and sub



## unnervingfalcon (Feb 14, 2011)

So these new"er" towers that I just attached are PSB Century 800i's. Two 8" drivers and a 1" tweeter. Here are the specs.

They have dual 8 inch woofers and a 1 inch textile dome tweeter. Power Handling (RMS): 10-200 Watts RMS Frequency Response: 48-20000 Sensitivity (dB): 92 dB Impedance (Ohms): 8 Ohms Weight (lbs): 42 lbs. Dimensions (w/h/d): 10x35x13.5 in. (width/height/depth)

The Sub is a PSB Alpha Subzero 8". It has a sub crossover frequency dial that says 50 to 150. Also has a 0 or 180 phase.

My Onkyo tx-sr608 7.2 did its Audyssey 2EQ test and set the fronts to 40 hz and LFE to 120 hz.

I did some reading on other sites and set the fronts to full range towers and then set the LFE to 80 hz. 
Then set the crossover on the sub to 50 hz. Phase has always been 0 degrees. Sub is beside the right front tower.

My question is..... is this set properly?


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## Guest (Mar 15, 2011)

No it isn't. Break out the owners manual for your sub. Because you are setting the crossover using the AVR and LFE out, the sub should either have a LFE only input, a switch to turn the internal crossover off (this is what mine has), or the instructions will tell you to turn the crossover all the way up.

Right now, you are crossed over at 80hz (probably a 12db slope) and then you are filtering out again at the sub at 50hz. You don't want to filter at all at the sub.


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## unnervingfalcon (Feb 14, 2011)

Generic said:


> No it isn't. Break out the owners manual for your sub. Because you are setting the crossover using the AVR and LFE out, the sub should either have a LFE only input, a switch to turn the internal crossover off (this is what mine has), or the instructions will tell you to turn the crossover all the way up.
> 
> Right now, you are crossed over at 80hz (probably a 12db slope) and then you are filtering out again at the sub at 50hz. You don't want to filter at all at the sub.


There is a LFE input right and left but not switch to turn off crossover. There is also a volume. I just thought that since the towers start at 48 hz that the sub should be set to 50 hz. The LFE on the receiver can only go as low as 80 hz.

So you think I should set the sub to 150 hz? What about the reciever?


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## Guest (Mar 15, 2011)

unnervingfalcon said:


> There is a LFE input right and left but not switch to turn off crossover. There is also a volume. I just thought that since the towers start at 48 hz that the sub should be set to 50 hz. The LFE on the receiver can only go as low as 80 hz.
> 
> So you think I should set the sub to 150 hz? What about the reciever?


If your sub has a LFE input, then use that. Then your subs crossover will not be used at all. It is okay that your speakers are rated at 48hz. That is most likely at -3b. Who knows where the roll-off starts. 60hz? Who knows... By crossing over at 80hz, your mains won't have a roll-off, other then what the crossover controls.

Download REW and then try and match the volume of your mains to the sub so they are the exact same volume. Or a db meter and some pink noise test tones or something. Once the volume matches, they should flow together really well.


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## unnervingfalcon (Feb 14, 2011)

Generic said:


> If your sub has a LFE input, then use that. Then your subs crossover will not be used at all. It is okay that your speakers are rated at 48hz. That is most likely at -3b. Who knows where the roll-off starts. 60hz? Who knows... By crossing over at 80hz, your mains won't have a roll-off, other then what the crossover controls.
> 
> Download REW and then try and match the volume of your mains to the sub so they are the exact same volume. Or a db meter and some pink noise test tones or something. Once the volume matches, they should flow together really well.


So if they won't have enough roll off, what should the receiver crossover be set at?


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## Guest (Mar 15, 2011)

I would set it at 80hz. Your speakers probably start a roll off between 60 and 50hz (that is just a guess), but should easily be able to play flat at 80hz.

80hz is the THX standard crossover point. It is suppose to be a point where you shouldn't hear where the sub is coming from, but this is very debatable, but it is a good starting point. I personally still like them in the front near the mains. In the middle if possible. Keeping them with the fronts should also keep audio delays the same as the mains. For people who aren't skilled or care enough (like myself) to bother with phase correction, having the sub with the mains is my personal preference.


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## bambino (Feb 21, 2010)

Just the way i have my system setup. My Mains are set to full and i have the sub at 80hz to my ears it sounds great and when listening to music there is no need for a sub IMO.:T


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## gdstupak (Jul 13, 2010)

Falcon,
The easiest way is this:
-On the sub: phase set to 0,,, crossover set at highest freq,,, you'll have to play with the volume.
-In the AVR: set ALL SPEAKER'S (including fronts) crossovers to 80hz (this will send all information below 80hz to the sub),,, for the LFE crossover: if the sub is at the front of the room, set it to 120hz, if the sub is not at the front of the room, set it to 80hz.

If you want to custom tailor your settings to your speakers, and if you want to get more invovled, do this:
-Get a CD/DVD that has test tones (or use REW) so you can hear how low your speakers will play.
-On the sub: you'll have to play with the phase to get your sub and main speakers to work together,,, crossover set at highest freq,,, you'll have to play with the volume.
-In the AVR: Set the crossovers of each speaker according to how low they will play flat (if the left/right speakers play flat down to 48hz, set those speaker's crossovers to 50hz (this will send any information below 50hz to the sub)),,, for the LFE crossover: if the sub is at the front of the room, set it to 120hz, if the sub is not at the front of the room, set it to 80hz.

If you don't mind missing most of the sound that is sent to the main speakers that is below 48hz, go ahead and set the main speakers to FULL.


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## bambino (Feb 21, 2010)

Evidently not all AVR's are created equal, as mine holds the settings for each mode that it is in so missing out on content is a non issue for me.:dontknow:


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## gdstupak (Jul 13, 2010)

Mine uses the same settings for all modes. For me, it doesn't matter what mode it's in, that one setting sounds good to me for everything.

And there's nothing wrong with running fronts as FULL all the time. Every person and every rig is different. Falcon may find it to sound best that way.


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## bambino (Feb 21, 2010)

What i meant glenn, (& maybe you undertsood what i was saying) but for each input being it Sat, HDP, CD or whatever input i have the AVR on, whatever settings i have those particular inputs set to they stay the same, so, just for example: if i have pure direct set for CD and multi-channel in for the HDP then dolby pro, and whatever level settings and crossover setting are set to that specific input. 

Hope i made sense in my response.:scratch:


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## Mark Techer (Jan 17, 2008)

unnervingfalcon said:


> RMS Frequency Response: 48-20000 Sensitivity (dB): 92 dB Impedance (Ohms): 8 Ohms Weight (lbs): 42 lbs. Dimensions (w/h/d): 10x35x13.5 in. (width/height/depth)
> My question is..... is this set properly?


The idea is to have a flat response from 20~20K for your LCRs. Sub-woofers are employed when the speakers (like yours) do not extent to 20Hz. You therefore need to find the point where the LCRs run out so you can splice in the SUB. I am guessing that because your front L and R speakers are towers, that your centre speaker will not be the same and as a result, it may require an even higher crossover point. If it were my system, I would be crossing over at the same frequency so that the feed to all three LCRs is identical.


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## Theresa (Aug 23, 2010)

Listening to classical and jazz is greatly enhanced for me by using a sub and keeping my mains HPF at 80Hz.


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