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Discussion Starter #1 (Edited)
For the above if I was to have time to do ALL that I need for analysis what would I need e.g. for timing/distance, phase, polarity, crossovers etc prior to EQ?

Also after EQ which measurements would be affected?

Also order of measurements?

This is to take full advantage of measuring time.

Thoughts on these please?

Front Left (full range 0 - 20,000hz)
Right Right (full range 0 - 20,000hz)
Both Left & Right (full range 0 - 20,000hz)

Sub 1 (crossover turned off)
Sub 2 (crossover turned off)
Both Sub 1 & 2 (crossover turned off)

Also mains repeated with different crossovers applied e.g 60Hz, 80Hz ,100Hz etc

Thanks in advance
 

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This is a very general question that may best be addressed by a book or via the frequently posted links to setup advice that we often see here. It is difficult to offer opinions regarding "All measurements needed for Analysis for 5.2 System". The specific context is very important.

More specific questions will get more helpful answers.
 

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Discussion Starter #3 (Edited)
This is a very general question that may best be addressed by a book or via the frequently posted links to setup advice that we often see here. It is difficult to offer opinions regarding "All measurements needed for Analysis for 5.2 System". The specific context is very important.

More specific questions will get more helpful answers.
Thanks for your advice

OK here we go

1. Does EQ alter timing, distance, phase, polarity, SPL level?
2. The order i should approach for phase, polarity, distance, SPL level, EQing, for all channels?

Thank you
 

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Thanks for your advice

OK here we go

1. Does EQ alter timing, distance, phase, polarity, SPL level?
2. The order i should approach for phase, polarity, distance, SPL level, EQing, for all channels?

Thank you
1. EQ does not impact Polarity.

For you, me, and everyone else using "minimum phase" IIR filters, any change via EQ to improve SPL will also change the phase response. You can easily investigate the extent of various changes by doing a loopback test that includes your EQ unit in the loopback. Set a boost or cut filter and take a measurement, You will then see both the affect on SPL and the phase. For those that use a unit capable of "linear phase" filters" (available when using FIR filters) then they can change the SPL and the Phase either together or separately.

I would expect the normal minimum phase EQ adjustments to not be an issue as the speaker response tends to be largely minimum phase anyway. That is, we would want the phase adjustments that go with the SPL adjustment to be applied.

There is also an excess phase in a speaker that is the phase portion in excess or the minimum phase portion. That portion will still remain when using minimum phase IIR filters.

There are varied and strong opinions on if and how to address phase response. My understanding of the research I have seen referenced is that it used test signals and did not find an impact until phase/GD levels exceeded those of most all speaker designs. The signals were selected to show a problem easier than with normal program material.

I did some testing recently using some of my normal music and removed the excess phase portion. I specifically chose one of my setups with steep XO filters for both SW-MW and also MW-TW. That setup has very close phase tracking between drivers through the XO regions, but the steep filters creates 900° of excess phase. Much more that most all commercial speaker designs. I could not detect the difference in my system. I also tried it through headphones using ABX testing methodology and again was not able to hear the difference. My experience not the best to consider however as my hearing is substandard and I use only one song for the testing. There are plenty of other people that indicate they easily hear a large improvement when the phase is linearized. I'm skeptical, but may implement this anyway for music as I have figured out how to do it in my system with additional equipment.

If you are concerned with SW EQ impacting on the timing of the handoff to the mains it is probably not enough to worry about. I would however recommend at least a rough EQ be done on the SW to smooth it before setting the timing/distance. That is probably unnecessary however as the impact is probably negligible in that regard. We can always confirm/reset the timing again after a major SW EQ change if we have a concern.

2. It's easy to find different opinions on this as well and again my opinion will depend on the individual setup.
My general answer for order would be:
> Get SWs working well together for SPL in listening area (various ways to do this)
> Set timing/distance for the mains. (various ways to do this)
> Confirm/set timing/distance of the SWs for smooth handoff to the mains. (various ways to do this)
> EQ the mains if needed/desired (various ways to do this)
[This ignores room design, room treatments, speaker/LP locations as you did not mention these.]

Polarity is a difficult concept. The only easy answer is that the polarity of the FL and FR must be the same in all cases. In many cases the CC is designed to match correctly with the FL and FR. If a disparate design is used the "correct" polarity can probably be argued as it may well be a tradeoff. The widely varying designs of surrounds often places them into this category also.

All of this is a hobbyist perspective. It is completely possible, and possibly very common, to plug a HT system together, run the automated setup routine and get a result that equals all this manual work. I would not argue that fine tuning some of these characteristics results in a significantly better sounding system. Early on my objective was to meet or exceed the results of using Audyssey XT and it took me a while to get there. I prefer my more recent setups, but mostly because the Audyssey house curve was too sharp for my taste. I much prefer my own house curve with my setup.
 

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Thanks for your advice

OK here we go

1. Does EQ alter timing, distance, phase, polarity, SPL level?
2. The order i should approach for phase, polarity, distance, SPL level, EQing, for all channels?

Thank you
1. EQ does not impact Polarity.

For you, me, and everyone else using "minimum phase" IIR filters, any change via EQ to improve SPL will also change the phase response. You can easily investigate the extent of various changes by doing a loopback test that includes your EQ unit in the loopback. Set a boost or cut filter and take a measurement, You will then see both the affect on SPL and the phase. For those that use a unit capable of "linear phase" filters" (available when using FIR filters) then they can change the SPL and the Phase either together or separately.

I would expect the normal minimum phase EQ adjustments to not be an issue as the speaker response tends to be largely minimum phase anyway. That is, we would want the phase adjustments that go with the SPL adjustment to be applied.

There is also an excess phase in a speaker that is the phase portion in excess or the minimum phase portion. That portion will still remain when using minimum phase IIR filters.

There are varied and strong opinions on if and how to address phase response. My understanding of the research I have seen referenced is that it used test signals and did not find an impact until phase/GD levels exceeded those of most all speaker designs. The signals were selected to show a problem easier than with normal program material.

I did some testing recently using some of my normal music and removed the excess phase portion. I specifically chose one of my setups with steep XO filters for both SW-MW and also MW-TW. That setup has very close phase tracking between drivers through the XO regions, but the steep filters creates 900° of excess phase. Much more that most all commercial speaker designs. I could not detect the difference in my system. I also tried it through headphones using ABX testing methodology and again was not able to hear the difference. My experience not the best to consider however as my hearing is substandard and I use only one song for the testing. There are plenty of other people that indicate they easily hear a large improvement when the phase is linearized. I'm skeptical, but may implement this anyway for music as I have figured out how to do it in my system with additional equipment.

If you are concerned with SW EQ impacting on the timing of the handoff to the mains it is probably not enough to worry about. I would however recommend at least a rough EQ be done on the SW to smooth it before setting the timing/distance. That is probably unnecessary however as the impact is probably negligible in that regard. We can always confirm/reset the timing again after a major SW EQ change if we have a concern.

2. It's easy to find different opinions on this as well and again my opinion will depend on the individual setup.
My general answer for order would be:
> Get SWs working well together for SPL in listening area (various ways to do this)
> Set timing/distance for the mains. (various ways to do this)
> Confirm/set timing/distance of the SWs for smooth handoff to the mains. (various ways to do this)
> EQ the mains if needed/desired (various ways to do this)
[This ignores room design, room treatments, speaker/LP locations as you did not mention these.]

Polarity is a difficult concept. The only easy answer is that the polarity of the FL and FR must be the same in all cases. In many cases the CC is designed to match correctly with the FL and FR. If a disparate design is used the "correct" polarity can probably be argued as it may well be a tradeoff. The widely varying designs of surrounds often places them into this category also. The SWs polarity does not matter as a good handoff is possible either way assuming the timing/distance is properly set for the chosen polarities. There is a tradeoff of characteristics involved.

All of this is a DIY hobbyist perspective. It is completely possible, and possibly very common, to plug a HT system together, run the automated setup routine and get a sonic result that equals all this manual work. I would not argue that fine tuning each of these characteristics results in a significantly better sounding system. Early on my objective was to meet or exceed the results of using Audyssey XT and it took me a while to get there. I prefer my more recent setups, but mostly because the Audyssey house curve was too sharp sounding for my taste. I much prefer my own house curve with my setup. Other than the obvious impact of SPL changes that are easily apparent on any system, I would not ascribe a great importance to fine tuning the other characteristics. It's more like the comment above regarding the linear phase question. If we enjoy fine tuning the system, and get peace of mind by doing it, then why not.
 

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Discussion Starter #6
1. EQ does not impact Polarity.

For you, me, and everyone else using "minimum phase" IIR filters, any change via EQ to improve SPL will also change the phase response. You can easily investigate the extent of various changes by doing a loopback test that includes your EQ unit in the loopback. Set a boost or cut filter and take a measurement, You will then see both the affect on SPL and the phase. For those that use a unit capable of "linear phase" filters" (available when using FIR filters) then they can change the SPL and the Phase either together or separately.

I would expect the normal minimum phase EQ adjustments to not be an issue as the speaker response tends to be largely minimum phase anyway. That is, we would want the phase adjustments that go with the SPL adjustment to be applied.

There is also an excess phase in a speaker that is the phase portion in excess or the minimum phase portion. That portion will still remain when using minimum phase IIR filters.

There are varied and strong opinions on if and how to address phase response. My understanding of the research I have seen referenced is that it used test signals and did not find an impact until phase/GD levels exceeded those of most all speaker designs. The signals were selected to show a problem easier than with normal program material.

I did some testing recently using some of my normal music and removed the excess phase portion. I specifically chose one of my setups with steep XO filters for both SW-MW and also MW-TW. That setup has very close phase tracking between drivers through the XO regions, but the steep filters creates 900° of excess phase. Much more that most all commercial speaker designs. I could not detect the difference in my system. I also tried it through headphones using ABX testing methodology and again was not able to hear the difference. My experience not the best to consider however as my hearing is substandard and I use only one song for the testing. There are plenty of other people that indicate they easily hear a large improvement when the phase is linearized. I'm skeptical, but may implement this anyway for music as I have figured out how to do it in my system with additional equipment.
Thanks again, so no use trying not much to gain?

If you are concerned with SW EQ impacting on the timing of the handoff to the mains it is probably not enough to worry about. I would however recommend at least a rough EQ be done on the SW to smooth it before setting the timing/distance. That is probably unnecessary however as the impact is probably negligible in that regard. We can always confirm/reset the timing again after a major SW EQ change if we have a concern.

2. It's easy to find different opinions on this as well and again my opinion will depend on the individual setup.
My general answer for order would be:
> Get SWs working well together for SPL in listening area (various ways to do this)
At this stage SPL, phase, EQ and timing/distance or just SPL?

> Set timing/distance for the mains. (various ways to do this)
Can do that, wouldn't mind looking at the different ways of doing this.
Can this be done with a USB mic?
Is this done with the crossover active or turn the crossover off?

> Confirm/set timing/distance of the SWs for smooth handoff to the mains. (various ways to do this)
Is this done with the crossover active in the reciever or turn off?

> EQ the mains if needed/desired (various ways to do this)
Have the DSpeaker Antimode Dual Core 2.0 for this.

[This ignores room design, room treatments, speaker/LP locations as you did not mention these.]
Speaker/LP locations are all set with some very minor chances of moving, (inches).

Polarity is a difficult concept. The only easy answer is that the polarity of the FL and FR must be the same in all cases. In many cases the CC is designed to match correctly with the FL and FR. If a disparate design is used the "correct" polarity can probably be argued as it may well be a tradeoff. The widely varying designs of surrounds often places them into this category also. The SWs polarity does not matter as a good handoff is possible either way assuming the timing/distance is properly set for the chosen polarities.
The front three are of the same design, surrounds are different.

There is a tradeoff of characteristics involved.
How is there a tradeoff?


All of this is a DIY hobbyist perspective. It is completely possible, and possibly very common, to plug a HT system together, run the automated setup routine and get a sonic result that equals all this manual work. I would not argue that fine tuning each of these characteristics results in a significantly better sounding system. Early on my objective was to meet or exceed the results of using Audyssey XT and it took me a while to get there. I prefer my more recent setups, but mostly because the Audyssey house curve was too sharp sounding for my taste. I much prefer my own house curve with my setup. Other than the obvious impact of SPL changes that are easily apparent on any system, I would not ascribe a great importance to fine tuning the other characteristics. It's more like the comment above regarding the linear phase question. If we enjoy fine tuning the system, and get peace of mind by doing it, then why not.
At what stage would you set the crossover between the mains and subs, e.g. before timing/distance, EQ etc?

Never liked what EQ YPAO set.

All comes down to taste in EQ etc, but others distance etc combines to be the best in the range.

Thanks again
 

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so no use trying not much to gain?
An interesting conclusion. Not the one I would have expected.

At this stage SPL, phase, EQ and timing/distance or just SPL?
All.

Can do that, wouldn't mind looking at the different ways of doing this.
One way is all that is needed to get the job done.

Can this be done with a USB mic?
Yes, Use a measuring tape.

Is this done with the crossover active or turn the crossover off?
Active.

How is there a tradeoff?
Different speaker designs have different phase rotations. So what frequency range is best to align? We could align the phase through the SW to Main XO range, or we could align the arrival of the mid or high frequencies where we are more sensitivity to timing differences. I have no opinion on which is best.

At what stage would you set the crossover between the mains and subs, e.g. before timing/distance, EQ etc?
Initial settings - before step 1
 

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Discussion Starter #8
An interesting conclusion. Not the one I would have expected.
Thanks again

Now i read it again yeah the best answer.

For music SW > Mains crossover is it best to use steep slopes or whatever blends the best?

Thanks again
 

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For music SW > Mains crossover is it best to use steep slopes or whatever blends the best?
?? These 2 aren't exclusive of each other. We can have an acceptable blend at a wide variety of filter slopes.

In normal HT setups an AVR provides an electrical LR-24 LPF and a But-12 HPF. The intent is that main speakers themselves provide a But-12 HP acoustic filter at the same XO freq. Therefore, the resulting HPF is targeted to be LR-24 also. If those acoustic shapes are actually achieved and the timing alignment correctly set then the resulting LR-24 alignment has good SPL and phase tracking properties. There are really no other filter slope options within the standard HT setup. The AVR filters cannot be changed except for the XO freq.

In practice, the actual acoustical slopes will vary and the automated distance settings may sometimes be off the mark. As a result a manual adjustment to the timing can often be helpful, even if is not normally required.

If you are asking about manual setups of filters within a HTPC or a setup like mine with various XO filter choices then numerous choices can be made that results good SPL and phase alignments.

If your question is primarily regarding filter slopes then the only general consensus might be that linear phase filters should be used if the XO slopes exceed 48 dB/octave. Otherwise the GD is probably going to be a problem. As noted previously many people prefer a linear phase filter over any minimum phase filter.
 

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Discussion Starter #10
Thank again been alot of help.

I have red somewhere, where possible to have the steepest slope crossover for music, but depends on tools that are available so to speak.
 
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