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post #1 of 62 Old 09-04-2013, 10:26 AM - Thread Starter
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I just ran audyssey and it set the crossover for my mains at 120 hz. My mains go down to 36hz. My sub is klipsch sw-110. Its range is 28-120hz. http://www.crutchfield.com/p_714SW110B/Klipsch-SW-110.html#overview-tab .

Can I leave the crossover at the higher end of my sub with no problem. I am fine with the sub doing more low frequency. I just wanted to make sure it was ok to have a crossover set at the high end of my subs capabilities.
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post #2 of 62 Old 09-04-2013, 10:42 AM
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I just ran audyssey and it set the crossover for my mains at 120 hz.

What are your mains?

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post #3 of 62 Old 09-04-2013, 11:11 AM - Thread Starter
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post #4 of 62 Old 09-04-2013, 11:19 AM
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RF-52II definitely can take thrashing down to 80hz with ease. Set the crossover at 80Hz in AVR and check if you like the sound. You will have to bring your sub in phase with the mains wrt 80Hz.

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post #5 of 62 Old 09-04-2013, 11:23 AM - Thread Starter
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That's not what I'm asking. Can the sub effectively produce the 120 hz is what I want to know. Or will there be a "hole" in the sound. From what I've read, you shouldn't lower the crossover that audyssey gives you, only raise it.
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post #6 of 62 Old 09-04-2013, 11:23 AM
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Probable cause: The location you have located the RF 52s at is causing a peak around 120 Hz or a null somewhat below that.

If you can't relocate them, then your remaining alternative is bass traps.

A possible starting place for your investigations into bass traps if you are not already familiar with them: http://realtraps.com/
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post #7 of 62 Old 09-04-2013, 11:31 AM - Thread Starter
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I know my room isn't ideal for home theatre, but I have to work with what I got. I'm just curious if the sub will reproduce the 120 hz well, being that it is the highest hz the speaker is supposed to handle.
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post #8 of 62 Old 09-04-2013, 11:31 AM
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That's not what I'm asking. Can the sub effectively produce the 120 hz is what I want to know. Or will there be a "hole" in the sound. From what I've read, you shouldn't lower the crossover that audyssey gives you, only raise it.

Yes it can. Dial the crossover on the sub all the way to its max in order to bypass it. But if I had RF-52 II, I wouldn't cross them at 120Hz. As far as lowering the crossover is concerned, you can lower it to 80Hz. It isn't that low.

Audyssey says not to lower the crossover coz it has more filters in the lower octaves. 80hz isn't that low.

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post #9 of 62 Old 09-04-2013, 11:34 AM - Thread Starter
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I am using the lfe input on my sub, doesn't that nullify the crossover dial on my sub.
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post #10 of 62 Old 09-04-2013, 11:38 AM
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Originally Posted by murrots View Post

I am using the lfe input on my sub, doesn't that nullify the crossover dial on my sub.

Set the crossover dial on the sub as high as possible, just to make sure.
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post #11 of 62 Old 09-04-2013, 11:40 AM
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Originally Posted by murrots View Post

I am using the lfe input on my sub, doesn't that nullify the crossover dial on my sub.
Not sure of that, but it should be wide open.

Audyssey set your mains are 120hz? That does not sound right or maybe it is. I would have thought it would set them at 60hz or 80hz.
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post #12 of 62 Old 09-04-2013, 11:43 AM - Thread Starter
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Originally Posted by arnyk View Post

Set the crossover dial on the sub as high as possible, just to make sure.

The dial goes to 150 hz, so that would mean that anything under 150 would be played through the sub? Or will the individual crossover for each speaker that audyssey came up with still be in effect.
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post #13 of 62 Old 09-04-2013, 11:49 AM - Thread Starter
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Originally Posted by Reefdvr27 View Post

Not sure of that, but it should be wide open.

Audyssey set your mains are 120hz? That does not sound right or maybe it is. I would have thought it would set them at 60hz or 80hz.

I ran it a few times using different measurements. The first couple times it gave me 60-80, but this last time I researched more about mic placement and I put the mic in the recommended spots and it came up with those numbers. Now I watched the new star trek blu ray last night and it sounded amazing.
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post #14 of 62 Old 09-04-2013, 12:16 PM
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120 Hz is too high a crossover even for sats, and calls for a very much localized bass response. The purpose of a sub is to compliment your mains without drawing attention towards it. At 120 Hz, it is too difficult for sw-110 to blend effectively.
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The dial goes to 150 hz, so that would mean that anything under 150 would be played through the sub? Or will the individual crossover for each speaker that audyssey came up with still be in effect.

No matter what the crossover for the speakers is, your sub will play the low range redirected signal of your speakers as long as the crossover in AVR is less than 150. Also, not all the subs disable internal crossover when fed though LFE input. So, it is better to dial the crossover knob on the sub all the way to max.

One thing more, use one crossover setting. Your sub can be in phase at one xo frequency only. If you go with different xo for mains and different xo for CC and surrounds, you can phase align either your mains or CC and surrounds. This is so because of varying wavelengths of crossover frequencies.

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Originally Posted by braveheart123 View Post

120 Hz is too high a crossover even for sats, and calls for a very much localized bass response. The purpose of a sub is to compliment your mains without drawing attention towards it. At 120 Hz, it is too difficult for sw-110 to blend effectively.
No matter what the crossover for the speakers is, your sub will play the low range redirected signal of your speakers as long as the crossover in AVR is less than 150. Also, not all the subs disable internal crossover when fed though LFE input. So, it is better to dial the crossover knob on the sub all the way to max.

One thing more, use one crossover setting. Your sub can be in phase at one xo frequency only. If you go with different xo for mains and different xo for CC and surrounds, you can phase align either your mains or CC and surrounds. This is so because of varying wavelengths of crossover frequencies.

I've read in many posts on these forums that it is ok to have separate crossover settings for different speakers.
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post #16 of 62 Old 09-04-2013, 09:10 PM
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I've read in many posts on these forums that it is ok to have separate crossover settings for different speakers.

I didn't make this up. It's physics and you can't challenge the laws of it. The wavelength at 80Hz can't be similar to the same at 90Hz. Both require different electrical delay setting for your subwoofer to be in phase with speakers.

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post #17 of 62 Old 09-05-2013, 03:08 AM - Thread Starter
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Originally Posted by braveheart123 View Post

I didn't make this up. It's physics and you can't challenge the laws of it. The wavelength at 80Hz can't be similar to the same at 90Hz. Both require different electrical delay setting for your subwoofer to be in phase with speakers.

Then why do receivers have the option to set crossovers at different frequencies?

http://www.avforums.com/forums/av-amplifiers-receivers/1019893-crossover-speaker-settings-relation-bass-management.html
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post #18 of 62 Old 09-05-2013, 03:17 AM
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Then why do receivers have the option to set crossovers at different frequencies?

You can set the crossover anywhere you want depending on the type of speakers you use, but set same crossover for all the speakers.

That's the stupidity they commit over and over to offer flexibility to use different crossover for different speakers. It's like asking somebody to be physically present in VA, as well as, NY. You can only be at one place at one point in time. Your sub can be in phase @ only one frequency. That's the reason why speakers must be chosen carefully especially the front three.


Some receivers do have the option of lowering the 120Hz LFE low pass setting also. It should not be there. Reason being, if you lower LPF for LFE from 120 to, let's say, 80Hz; you create a huge hole in your LFE response. You will miss all the information from 80Hz to 120Hz.


Some features are there just for the heck of it with very little to no practical use. That's called marketing and staying in business wink.gif

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post #19 of 62 Old 09-05-2013, 04:02 AM - Thread Starter
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Ok, should I set the low pass filter on my sub to the highest setting and let the receiver do the rest. I realized that the lpf was set to 80hz on my sub.
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post #20 of 62 Old 09-05-2013, 04:03 AM - Thread Starter
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Ok, should I set the low pass filter on my sub to the highest setting and let the receiver do the rest. I realized that the lpf was set to 80hz on my sub.
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post #21 of 62 Old 09-05-2013, 05:09 AM
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Ok, should I set the low pass filter on my sub to the highest setting and let the receiver do the rest. I realized that the lpf was set to 80hz on my sub.

Yes dial the LPF on your sub to its max setting so that it does not interfere with AVR. Let your AVR do bass management.

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post #22 of 62 Old 09-05-2013, 05:48 AM - Thread Starter
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Originally Posted by braveheart123 View Post

Yes dial the LPF on your sub to its max setting so that it does not interfere with AVR. Let your AVR do bass management.

Ok, thanks.
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post #23 of 62 Old 09-05-2013, 09:36 AM
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Originally Posted by murrots View Post

Then why do receivers have the option to set crossovers at different frequencies?

http://www.avforums.com/forums/av-amplifiers-receivers/1019893-crossover-speaker-settings-relation-bass-management.html
Setting different crossovers for different speaker sets is perfectly fine to do. The crossovers don't set the phase, (as opposed to what another poster believes.) The phase/delays are set by the Distance settings of the speakers and subs. Since the distances can be set on a "per speaker" basis, and those distances are what determine the blend of the speakers and subwoofer(s), having them blend at different frequencies works just fine. (The proper technique for setting speaker Distances is a whole different discussion, but if performed properly, the crossover frequency doesn't matter.)

More importantly, using a single, global crossover frequency for all speakers doesn't allow one to take into account the different LF capabilities of different speakers in different in-room positions, nor their different room interactions. The proper crossover setting for the mains could be completely different than the proper crossover setting for the rear surrounds. Having the ability to set different crossovers for different speaker sets is a useful tool for proper system integration, not a "stupid" marketing ploy. Use the tool properly and it will get the job done.
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Some receivers do have the option of lowering the 120Hz LFE low pass setting also. It should not be there. Reason being, if you lower LPF for LFE from 120 to, let's say, 80Hz; you create a huge hole in your LFE response. You will miss all the information from 80Hz to 120Hz.

The LPF of LFE is a filter that is only applied to the LFE channel. It doesn't have any impact on the bass that is re-directed to the subwoofer output from the main channels. The LFE channel used to be filtered with a "brickwall" filter during the recording process. With the introduction of the "lossless" codec's, (Dolby TrueHD/DTS MA), the LFE channel became a "full range" channel, which means recording engineers have the "ability" to record content in the LFE channel all the way up to 20 kHz. The "guidance" from Dolby is that they filter the content at 80 Hz, but that is just a guidance, not a mandate. Therefore, newer receivers and pre/pro have a Low Pass, (High Cut), filter for the LFE channel. In many receivers, it is adjustable from 80 to 200 Hz. Some will tell you that the "best" setting is 120 Hz, but that is debatable. The filter is NOT a "brickwall" filter, so setting it to 120 Hz will allow content higher than 120 Hz to pass through, (albeit at a reduced level.) Here is a graph that shows the different LPF of LFE settings:



The blue trace is the old 120 Hz "brickwall" filter. The orange trace is an 80 Hz filter and the green trace is a 120 Hz filter. Note how much more content >120 Hz can get through a 120 Hz LPF. 80 Hz is generally considered the point at which humans can start to localize soundwaves. Note how much more >80 Hz content gets through with an 120 Hz filter than an 80 Hz filter. Theoretically, there should be little content >80 Hz, and no content >120 Hz in the LFE channel, but if there is such content, it should be removed by the filter. The 80 Hz LPF does a much better job of that than the 120 Hz setting. A lower LPF of LFE setting could help reduce the localization of the subwoofer by reducing the level of any content above the filter setting.

I use an 80 Hz setting of the LPF of LFE. It's a 24 dB/octave filter, so at 120 Hz, the LFE channel is down 6 dB from the 80 Hz level. That is certainly not a huge "hole" in the response. In fact, most recording engineers place very little content from 80 to 120 Hz in the LFE channel. Therefore, an 80 Hz setting of the LPF of LFE is hardly significant to the mostly non-existent content anyway. I suggest you try an 80 Hz setting and see if you can even notice the difference.

Again, the LPF of LFE is not just some "stupid" marketing feature. It's another tool to help with proper system integration.

Craig
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post #24 of 62 Old 09-05-2013, 10:39 AM - Thread Starter
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Are all receivers lpf for lfe 24db/octave filter? I have a marantz 5007.

Is it a good idea to set the crossover for speakers at an octave above their lowest rated frequency, say 120hz for a 60hz speaker?

Does a higher crossover help take stress off of the receiver and also produce better high and midrange sound from those speakers?
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post #25 of 62 Old 09-05-2013, 11:39 AM
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Setting different crossovers for different speaker sets is perfectly fine to do. The crossovers don't set the phase, (as opposed to what another poster believes.) The phase/delays are set by the Distance settings of the speakers and subs. Since the distances can be set on a "per speaker" basis, and those distances are what determine the blend of the speakers and subwoofer(s), having them blend at different frequencies works just fine. (The proper technique for setting speaker Distances is a whole different discussion, but if performed properly, the crossover frequency doesn't matter.)

More importantly, using a single, global crossover frequency for all speakers doesn't allow one to take into account the different LF capabilities of different speakers in different in-room positions, nor their different room interactions. The proper crossover setting for the mains could be completely different than the proper crossover setting for the rear surrounds. Having the ability to set different crossovers for different speaker sets is a useful tool for proper system integration, not a "stupid" marketing ploy. Use the tool properly and it will get the job done.

Who said crossovers set the phase/delays? What I meant, which should be a stark truth for a guy like you with close to 10K posts, was that differing frequencies have differing wavelengths. And in order for a sub to be in phase with the mains wrt MLP, the sub's distance in AVR has to be adjusted to add correct delay to the mains for different crossover frequencies.

Well if you think that the wavelengths of 17.8 ft @ 60Hz, 13.4 ft @ 80Hz, 10.7 ft @ 100 Hz are all the same; by all means cross your surrounds at 100Hz, CC at 80Hz, and mains at 60Hz keeping the same distance setting for the sub. Um sure when there is an explosion in a movie that gravitates around the front 3 speakers, you will have full impact.

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The LPF of LFE is a filter that is only applied to the LFE channel. It doesn't have any impact on the bass that is re-directed to the subwoofer output from the main channels.

Oh um so novice, I didn't know the difference between LFE and redirected bass and that LFE LPF setting of 120Hz was indeed for LFE only and there is no slope applied to it when the same is dropped to 90Hz...... come off it man

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post #26 of 62 Old 09-05-2013, 11:48 AM
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Originally Posted by murrots View Post

Are all receivers lpf for lfe 24db/octave filter? I have a marantz 5007.
Few manufacturers state the slopes of any of their HPF's or LPF's. It would certainly make sense for the LPF of LFE to be at least a 24 dB/octave, (4th order), slope, but you wouldd need to get confirmation of that from Marantz.
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Is it a good idea to set the crossover for speakers at an octave above their lowest rated frequency, say 120hz for a 60hz speaker?
Ideally, you want to set the crossovers at a point above the measured, in-room -3 dB point of each speaker. How far above that point is a matter of several things. First, the measured -3 dB point is measured at 75 dB. Most all speakers will have a completely different -3 dB point at 105 dB, (or full Reference Level.) Crossing over higher will provide the speakers and amps with more headroom so the output at the F3, ( the -3 dB frequency), can be higher. However, offsetting that is the fact that soundwaves become localizable, (locatable), at about 80 Hz, so crossing over above 80 Hz can make the subwoofer be localizable. If your sub is on the floor, in a corner or on the side or rear wall, you don't want the fundamental tone of things like deep male voices or bomb blasts, etc., to sound like they are coming from the sub. They should be integrated with the rest of the sound. To ensure that, the highest crossover for "best" system integration should ideally be 80 Hz. This goes back to system design. You want to design your surround system so the speakers are capable to below 80 Hz, with enough output to play to your required levels to the crossover frequency you've selected.

This is the fundamental reason why 80 Hz is so often quoted as the ideal starting crossover frequency. It provides the best compromise of system headroom with low subwoofer localization. But it requires speakers that can deliver <80 Hz output. Small satellites do cut the mustard. "LCR-type" speakers are the ideal solution for this type of a system. They are optimized for output to 50 to 60 Hz, low enough to use an 80 Hz crossover, but not so low that you're wasting LF extension capability in a speaker that will never be used to reproduce the deepest bass. This is why large floorstanders are inefficient in a system that uses subwoofers. They're designed to produce deep bass, but the bass all gets sent to the subs. As I said, this is all about system design. Chose speakers that do the job assigned to them effectively and efficiently and don't waste money on aspect of design that won't be utilized anyway.

An 80 Hz crossover also requires subwoofer(s) with >80 Hz output. To get a good blend around the crossover frequency, the subwoofer(s) must be capable of flat response to an actave above the crossover frequency. Then the LPF can properly do their job of blending the decreasing outptu of the subs with the increasing output of the speakers through the crossover region.
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Originally Posted by murrots View Post

Does a higher crossover help take stress off of the receiver and also produce better high and midrange sound from those speakers?
Yes, higher crossovers do relieve the receiver amps of the responsibility of powering the deepest bass. 20 Hz take twice as much power to reproduce as 40 Hz. 40 Hz takes twice as much power as 80 Hz dB. Reduce or eliminate the 20 - 80 Hz content and the amp has a lot more power to send for the >80 Hz content. This significantly reduces amplifier distortion and compression, and allows the entire system to play back louder and cleaner.

In addition, the excursion requirement for a woofer to produce 40 Hz vs. 80 Hz doubles, and doubles again to get to 20 Hz. The woofers can play back louder and cleaner if you eliminate the really deep content from the signal.

There are many reasons to use Bass Management to optimize a sound system. It requires using all the tools at your disposal properly. The best way to do that is with in-room measurements. Audyssey is a great system, but I have found that the results can often be improved on with in-room measurements. If you don't have measuring software, I highly encourage you to consider aquiring it, especially if you are really serious about optimizing your system.

Craig

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post #27 of 62 Old 09-05-2013, 12:05 PM
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Originally Posted by braveheart123 View Post

Who said crossovers set the phase/delays? What I meant, which should be a stark truth for a guy like you with close to 10K posts, was that differing frequencies have differing wavelengths. And in order for a sub to be in phase with the mains wrt MLP, the sub's distance in AVR has to be adjusted to add correct delay to the mains for different crossover frequencies.

Well if you think that the wavelengths of 17.8 ft @ 60Hz, 13.4 ft @ 80Hz, 10.7 ft @ 100 Hz are all the same; by all means cross your surrounds at 100Hz, CC at 80Hz, and mains at 60Hz keeping the same distance setting for the sub. Um sure when there is an explosion in a movie that gravitates around the front 3 speakers, you will have full impact.
It's great that you understand wavelengths. But this discussion isn't about wavelengths. It's about time. What you are missing is that, if the speaker distances are set correctly, then all the frequencies from the speakers and the subs will be timed correctly, no matter what frequency is being reproduced. It's not about frequency or wavelength. It's about arrival time, and arrival time is what the distance setting optimizes.

For example, if the sub is 15 ft. away from the primary listening/measuring position, and the LCR speakers are 10 ft. away, and the surrounds are 8 ft. away, then the subwoofer will fire first, the speakers will be delayed and fire about 5 ms later and the surrounds about 2 ms. after that. All the waves from all the speakers and sub(s) at all frequencies will arrive at the listening/measuring position at the same time. The different wavelengths of the various frequencies won't matter.

In your example, how would you deal with surrounds that need a 100 Hz crossover, a CC that needs an 80 Hz crossover and mains that need a 60 Hz crossover? If you set them all to the SAME crossover, at least 2 of the speakers sets will be less than optimized. If you set the global crossover to 100 Hz, you have localization from the subwoofer. If you set the global crossover to 80 Hz, that will be too low for the surrounds. If you set the global crossover to 60 Hz, that will be too low for the surrounds and the CC. There is no global crossover that is ideal for each of these different speakers. The whole reason why manufacturers developed crossovers selectable by speaker group is to accommodate systems that have speakers with different LF capabilities at different positions in the system.

Craig

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post #28 of 62 Old 09-05-2013, 12:06 PM
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Quote:
Originally Posted by braveheart123 View Post

Who said crossovers set the phase/delays? What I meant, which should be a stark truth for a guy like you with close to 10K posts, was that differing frequencies have differing wavelengths. And in order for a sub to be in phase with the mains wrt MLP, the sub's distance in AVR has to be adjusted to add correct delay to the mains for different crossover frequencies.

Well if you think that the wavelengths of 17.8 ft @ 60Hz, 13.4 ft @ 80Hz, 10.7 ft @ 100 Hz are all the same; by all means cross your surrounds at 100Hz, CC at 80Hz, and mains at 60Hz keeping the same distance setting for the sub. Um sure when there is an explosion in a movie that gravitates around the front 3 speakers, you will have full impact.
Oh um so novice, I didn't know the difference between LFE and redirected bass and that LFE LPF setting of 120Hz was indeed for LFE only and there is no slope applied to it when the same is dropped to 90Hz...... come off it man

I actually haven't found this to be true. Once I run Audyssey and dial in the distance (read: phase), I can change the crossover frequency of my center or mains without seeing any phase issues in my measurements. What I would see, if I were to do that type of testing, is a difference in max levels--my mains are not going to play 40 Hz content as loudly or as cleanly as my subs. But I don't generally do max spl/compression testing with my mains/center crossed that low, anyway.

Just my 2 cents.
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post #29 of 62 Old 09-05-2013, 12:09 PM
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you don't want to play any frequencies on your sub that can be played by your main speakers. It will sound boomy and distorted.
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post #30 of 62 Old 09-05-2013, 12:18 PM
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Originally Posted by MitchFlorida View Post

you don't want to play any frequencies on your sub that can be played by your main speakers. It will sound boomy and distorted.

Over-generalization. When playing movie content, I cross at 80 Hz. When playing music, I cross at 100 Hz. No boom or distortion.
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