Best cross over freq when sub does 30 Hz-150 Hz ?

[Deleted member 4644]

I have a Polk CS2 center and Monitor 60 fronts set up. 6.5 and 5.25" drivers respectively. They have a rated response of

Fronts

Overall Frequency Response 38Hz - 25kHz
Lower -3dB Limit 48Hz
Upper -3dB Limit 24kHz
Efficiency 90 dB
Crossover 2.25kH, second order high and low pass

Center

Overall Frequency Response 55Hz - 25kHz
Lower -3dB Limit 60Hz
Upper -3dB Limit 24kHz
Efficiency 90 dB
Crossover 2.3kHz, second order high and low pass



**** My 10" Onkyo sub has a rated response of 30 Hz-150 Hz. *****

I can set the receiver/sub cross over from 60hz to 160hz in 5 steps.



Should I set my Onkyo receiver to "large" or "small" for the fronts/center?

Should I set my sub crossover to 80hz or 100hz?

 

[YOyoYOhowsDAjello]

I would try "small" and 80hz to see how that works.

 

[thomsbrain]

Originally posted by: YOyoYOhowsDAjello
I would try "small" and 80hz to see how that works.

This.

 

[MustISO]

This would also be a good time to get an SPL meter (if you don't have one) and calibrate the speakers.

 

[erwos]

"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

 

[sdifox]

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

 

[PurdueRy]

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

 

[Deleted member 4644]

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

Can you explain what the "rated -3db" means compared to the other ratings?

 

[sdifox]

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

There is an offset table floating around on the internet to correct the bias of the rat shack meter.

my mains have 4 6.5" and I feed them full range. And passing the below 80 stuff to the sub at the same time.

 

[EvilYoda]

Originally posted by: sdifox

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

There is an offset table floating around on the internet to correct the bias of the rat shack meter.

my mains have 4 6.5" and I feed them full range. And passing the below 80 stuff to the sub at the same time.

4x 6.5" drivers is quite different than most people's speakers that just have the one. And depending on the capabilities of your specific drivers, who knows...my Dyn's can go quite low, but I don't need to thanks to my beautiful DD12

 

[Deleted member 4644]

I have 3x 5.25" drivers in my monitor 60s. (I guess that is why it has a fairly low range capability).

What are the pros and cons of letting those drivers do the work compared to my Onkyo sub?

 

[sdifox]

Originally posted by: Deleted member 4644
I have 3x 5.25" drivers in my monitor 60s. (I guess that is why it has a fairly low range capability).

What are the pros and cons of letting those drivers do the work compared to my Onkyo sub?

for movie, probably no difference, but when you get into multi channel high def music, it is desirable to have full range all around.

You mentioned Onkyo sub. Do you know the diameter of the woofer?

 

[sdifox]

Originally posted by: EvilYoda

Originally posted by: sdifox

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

There is an offset table floating around on the internet to correct the bias of the rat shack meter.

my mains have 4 6.5" and I feed them full range. And passing the below 80 stuff to the sub at the same time.

4x 6.5" drivers is quite different than most people's speakers that just have the one. And depending on the capabilities of your specific drivers, who knows...my Dyn's can go quite low, but I don't need to thanks to my beautiful DD12

For HT purpose I agree, just let the sub handle it. But when it comes to HD Audio, full range all around is preferred.

 

[PurdueRy]

Originally posted by: Deleted member 4644
I have 3x 5.25" drivers in my monitor 60s. (I guess that is why it has a fairly low range capability).

What are the pros and cons of letting those drivers do the work compared to my Onkyo sub?

The sub may or may not do certain ranges with less distortion and other negative effects. Otherwise, the most critical thing is that you don't get a null at your crossover frequency due to the speakers and sub not summing correctly.

 

[PurdueRy]

Originally posted by: sdifox

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

There is an offset table floating around on the internet to correct the bias of the rat shack meter.

my mains have 4 6.5" and I feed them full range. And passing the below 80 stuff to the sub at the same time.

Oh yes there is an offset table but if you think that holds true for all the omni-directional mics made by radio shack...well...you might be mistaken. Not to mention that offset table is pretty widely spread and isn't particularly useful for detecting small room nulls and resonances with a great deal of accuracy.

 

[PurdueRy]

Also OP I see you are asking about your sub crossover. Assuming you have a receiver which has a built in crossover, set the one on the sub as high as it will go. If you are asking about the sub/LFE crossover setting on your receiver(assuming that you have other crossover settings for each speaker) I also typically set this as high as it will go. The reasoning behind this is because, in my opinion, there is no reason to filter the LFE channel on the high end. It was designed specifically to be only sent to the subwoofer. Your other crossover settings are FAR more important.

Originally posted by: Deleted member 4644

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

Can you explain what the "rated -3db" means compared to the other ratings?

-3dB just means where the speaker begins to lose significant volume at a certain frequency such that it can have a discernable affect on the sound. This, in a good speaker, should be the point on the low end where the frequency response begins to rapidly drop off. Because of this, you don't want to set your crossover to this point because it typically will sum to a small null rather than a flat response.

 

[Deleted member 4644]

Originally posted by: sdifox

Originally posted by: Deleted member 4644
I have 3x 5.25" drivers in my monitor 60s. (I guess that is why it has a fairly low range capability).

What are the pros and cons of letting those drivers do the work compared to my Onkyo sub?

for movie, probably no difference, but when you get into multi channel high def music, it is desirable to have full range all around.

You mentioned Onkyo sub. Do you know the diameter of the woofer?

10", and freq specs as above.

 

[Deleted member 4644]

Originally posted by: PurdueRy
Also OP I see you are asking about your sub crossover. Assuming you have a receiver which has a built in crossover, set the one on the sub as high as it will go. If you are asking about the sub/LFE crossover setting on your receiver(assuming that you have other crossover settings for each speaker) I also typically set this as high as it will go. The reasoning behind this is because, in my opinion, there is no reason to filter the LFE channel on the high end. It was designed specifically to be only sent to the subwoofer. Your other crossover settings are FAR more important.

Originally posted by: Deleted member 4644

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

Can you explain what the "rated -3db" means compared to the other ratings?

-3dB just means where the speaker begins to lose significant volume at a certain frequency such that it can have a discernable affect on the sound. This, in a good speaker, should be the point on the low end where the frequency response begins to rapidly drop off. Because of this, you don't want to set your crossover to this point because it typically will sum to a small null rather than a flat response.

Each speaker has Large or Small. And the sub "crossover" can be set from 60hz to 150hz in about 5 steps.

 

[PurdueRy]

Originally posted by: Deleted member 4644

Originally posted by: PurdueRy
Also OP I see you are asking about your sub crossover. Assuming you have a receiver which has a built in crossover, set the one on the sub as high as it will go. If you are asking about the sub/LFE crossover setting on your receiver(assuming that you have other crossover settings for each speaker) I also typically set this as high as it will go. The reasoning behind this is because, in my opinion, there is no reason to filter the LFE channel on the high end. It was designed specifically to be only sent to the subwoofer. Your other crossover settings are FAR more important.

Originally posted by: Deleted member 4644

Originally posted by: PurdueRy

Originally posted by: sdifox

Originally posted by: erwos
"You could calculate it with an SPL and a few hours of work... or just put in 80hz, like everyone else."

I think 80Hz is too high for 6.5"

It will depend entirely on the room. If the fronts get a little reinforcement from the room they could potentially hold up a bit lower than the rated -3dB. The only way to know this, however, is to get the necessary equipment to accurately measure room response...which can be done with a SPL meter but the typical radio shack variety aren't particularly accurate.

Can you explain what the "rated -3db" means compared to the other ratings?

-3dB just means where the speaker begins to lose significant volume at a certain frequency such that it can have a discernable affect on the sound. This, in a good speaker, should be the point on the low end where the frequency response begins to rapidly drop off. Because of this, you don't want to set your crossover to this point because it typically will sum to a small null rather than a flat response.

Each speaker has Large or Small. And the sub "crossover" can be set from 60hz to 150hz in about 5 steps.

Ah ok, so this is probably a fixed crossover receiver meaning you have to pick one crossover for all the speakers. I would set your sub crossover on your receiver to 80 Hz unless you have the urge to make more accurate measurements of your room. Set all the speakers to small.

If you have a crossover setting on your subwoofer itself disable it or set it as high as it will go.

 

[sdifox]

Originally posted by: Deleted member 4644

10", and freq specs as above.

<-- fail... I somehow read the first part but missed the sub part.

Did you try a frequency sweep to determine where the sub really tops out on the high end of the frequency? Same with your speakers.

Setting it to 80 is a safe bet. I am just wondering if you can get better sound.

 

[Deleted member 4644]

sdifox, if I can go as low as 60hz, should I try that? Or will my speakers fall off too much even if they are rated down to 38 hz themselves?

 

[PurdueRy]

Originally posted by: Deleted member 4644
sdifox, if I can go as low as 60hz, should I try that? Or will my speakers fall off too much even if they are rated down to 38 hz themselves?

Ignore the 38 Hz rating. That's likely -10 to -6dB down already. The 48Hz is much more accurate and this shows you how fast speakers can fall off on the low end especially if they are ported. That's why I recommend staying away from 60 Hz without making more measurements because you're only approx 10Hz at that point from where your speakers "corner frequency" is.

 

[Deleted member 4644]

Thx PurdueRy, I just learned a lot.

 

[sdifox]

Originally posted by: Deleted member 4644
sdifox, if I can go as low as 60hz, should I try that? Or will my speakers fall off too much even if they are rated down to 38 hz themselves?

you may be able to hit 60 without losing too many dbs, but I doubt you can realistically hit 38 without losing a lot of dbs.