Proper crossovers for my home theater?

K

Kyle Braunlich

Junior Audioholic
What would the ideal crossover be as well as the lowest crossover you would put on each of these speakers?
Fronts - Definitive sm55’s
Center - Definitive ProCenter 1000
Surround - Definitive sr-9040 bipolar speakers
 
WaynePflughaupt

WaynePflughaupt

Audioholic Samurai
The ideal crossover frequency is typically 70-90 Hz.

The lowest crossover setting is generally recommended to be about one octave above the speaker’s rated low frequency extension.

Regards,
Wayne A. Pflughaupt
 
K

Kyle Braunlich

Junior Audioholic
The ideal crossover frequency is typically 70-90 Hz.

The lowest crossover setting is generally recommended to be about one octave above the speaker’s rated low frequency extension.

Regards,
Wayne A. Pflughaupt
What do you mean by one octave above the speakers low frequency extension. I assume if a speaker is rated at let’s say 47 hz you mean go one octave above. I am just not sure what an octave above a frequency would be. How many hz above?
 
WaynePflughaupt

WaynePflughaupt

Audioholic Samurai
One octave above a given frequency is double that figure. One octave below is half. – e.g. 30 Hz, 60 Hz, 120 Hz.

Regards,
Wayne A. Pflughaupt
 
S

SRL Acoustics

Enthusiast
What do you mean by one octave above the speakers low frequency extension. I assume if a speaker is rated at let’s say 47 hz you mean go one octave above. I am just not sure what an octave above a frequency would be. How many hz above?
an octave would double the frequency. In this case 94hz.
 
S

snakeeyes

Audioholic Ninja
What would the ideal crossover be as well as the lowest crossover you would put on each of these speakers?
Fronts - Definitive sm55’s
Center - Definitive ProCenter 1000
Surround - Definitive sr-9040 bipolar speakers
I believe the Def Tech website gives a suggestion for crossover on most.. The SR9040 suggestion is 100hz under the “Tech specs” section. Possibly in the manual download too.

https://www.definitivetechnology.com/products/sr9040#Support
 
S

snakeeyes

Audioholic Ninja
Yes I have found that. I just can’t find the other two. Only the low frequency response.
Since Def Tech exaggerates on the low end frequency response, it’s probably wise to look at the size of the driver as an indicator of crossover. I know there is a link for that but I am not remembering the site.

For example one 6in driver might get you to 80hz crossover. One 5in driver might only get you to 90hz crossover. There is some overlap here with what the speaker can do and the crossover frequency. Dual drivers can go a bit lower over a single driver. If you are noticing the speaker sounds like it is bottoming out, raise the crossover in increments of 10 until that stops.
 
K

Kyle Braunlich

Junior Audioholic
Since Def Tech exaggerates on the low end frequency response, it’s probably wise to look at the size of the driver as an indicator of crossover. I know there is a link for that but I am not remembering the site.

For example one 6in driver might get you to 80hz crossover. One 5in driver might only get you to 90hz crossover. There is some overlap here with what the speaker can do and the crossover frequency. Dual drivers can go a bit lower over a single driver. If you are noticing the speaker sounds like it is bottoming out, raise the crossover in increments of 10 until that stops.
Thank you for the advice. I’ll try that.
 
R

Russdawg1

Full Audioholic
Mains at 80hz and surrounds at 100hz and atmos at 180hz

Industry standards.
 
ryanosaur

ryanosaur

Audioholic Overlord
Would my center be considered a main speaker?
No, maybe... you can't lump it all together. ;) As was said before, it comes down to the frequency response of the speaker. If your center is only rated down to, say, 57Hz, and you cross over at 60 or 80, you could potentially damage it. It would take loud hard extended bass, but it could happen.
You've got to know what your speaker specs are to really get it right.
Though I agree with Russ, you can't apply a blanket standard if your speakers don't match that criteria.

For your Left and Right, the 1 octave up was 94Hz, so experiment with 90 and 100 on that... listen to hear which sounds better, and if you are creating any low distortion in the woofers. If you are, set it higher.

If your center has smaller woofers than your L/R speakers, you probably need to set the Crossover higher, more in line with your surrounds.

I'd recommend maybe calling the company with the model numbers and see if they can advise you. That said, I wouldn't set that procenter at 40hz. 100, maybe.
 
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K

Kyle Braunlich

Junior Audioholic
Definitive finally got back to me on what they recommend for their crossovers for my speakers (all Definitive). I just want to make sure that they are giving good information. I have always been told to go higher then these crossover recommendations. For the sr-9040 bi-polar surrounds, they said 120hz. The manual indicates 100hz. For the sm55 bookshelf and pro-center 1000 they recommend 60hz. I thought this might be a little low for my center speaker given the size. Thanks for any help!
-Kyle Braunlich
 
ryanosaur

ryanosaur

Audioholic Overlord
Heres a simple way to see what that little guy can do. BUT USE CAUTION!

I found POWER TOOLS by Bass Mekanik on Apple Music. I'm sure there are other ways/sources too... but get yourself some test tones, and see what that center channel can do. Start with your volume low, and with a higher tone, say 60 hz. Progressively work your way lower until it A: is beginning to distort. STOP IMMEDIATELY! B: the driver looks like it is going to pop out and fly through the wall. STOP IMMEDIATELY!
If that little guy is faithfully reproducing 30Hz. Kudos to DefTech. I don't buy it, but I'm also stubborn as all hell, being from MO, and need to believe it before I'll see it! :p

BTW: Do not blow your gear up. :oops: I will not replace it. :cool:
 
lovinthehd

lovinthehd

Audioholic Jedi
Interesting the manual for the procenter 1000 recommends 40hz xover yet they have an undefined lower response of 47 Hz (probably at least -6dB knowing them, maybe even -10dB). I don't trust DefTec specs much, and they don't provide much in the way of spec definitions, but a xover of 60 sounds low, too, I'd go with 80. Maybe 60 on the SM55s but I'd probably still go 80. At least, maybe even higher. Experiment and see if you have a preference....for surrounds 120 is reasonable I think. Might depend somewhat on your sub, what are you using?
 
K

Kyle Braunlich

Junior Audioholic
Interesting the manual for the procenter 1000 recommends 40hz xover yet they have an undefined lower response of 47 Hz (probably at least -6dB knowing them, maybe even -10dB). I don't trust DefTec specs much, and they don't provide much in the way of spec definitions, but a xover of 60 sounds low, too, I'd go with 80. Maybe 60 on the SM55s but I'd probably still go 80. At least, maybe even higher. Experiment and see if you have a preference....for surrounds 120 is reasonable I think. Might depend somewhat on your sub, what are you using?
Pro sub 1000
 
everettT

everettT

Audioholic Spartan
If your sub is capable, I'd try between 80 and 100hz. I definitely wouldnt go below 80 with those speakers. What sub do you have?
 
everettT

everettT

Audioholic Spartan
Should have a mod move your other thread here so we are not jumping around.

As I asked in the other, what sub? What avr?
 
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