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Stereo vs mono - what is the ideal frequency response?

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Thomas_A

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Thread Starter #41
You don't need to do the experiment to know you can't rectify a cancellation. Also it's a moot point because as you allude to room reflections affect the situation.
There are not only cancelalations but variations up and down +/-2 dB. That Toole says the effect starts with the 1-2 kHz dip does not mean it ends there. How about the peak around 3-4 kHz?
 
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Thomas_A

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Thread Starter #42
The only thing to do, and correct thing to do, is have a neutral speaker. You shouldn't mess the speaker up because stereo creates problems
How can you be sure of that when e.g. the M106 apparently sounds good and in principle have the compensation built-in?
 

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#43
There are not only cancelalations but variations up and down +/-2 dB. That Toole says the effect starts with the 1-2 kHz dip does not mean it ends there. How about the peak around 3-4 kHz?
What about it?

Now change listening position and you need a different eq.
 

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#44
How can you be sure of that when e.g. the M106 apparently sounds good and in principle have the compensation built-in?
What compensation specifically does it have? Why would a fixed compensation be suitable in different rooms and configurations?
 
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Thomas_A

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Thread Starter #46
What about it?

Now change listening position and you need a different eq.
Yes, that applies also to a linear response. I refer to how the optimal stereo listening should be setup, including the listener.
 

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#47
It has a slightly higher output in the direct response between 1-2 kHz, lower output 2-4 kHz, and lower around 7-8 kHz.
Is this a deliberate for your puported reasons? Or is it just the way the speaker is?
 

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#48
Yes, that applies also to a linear response. I refer to how the optimal stereo listening should be setup, including the listener.
No it doesn't because the reflections will be different in every situation and room.
 

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#50
As I pointed out previously, deliberate design goal or coincidence?
Well speculate as much as you like but it doesn't really get us anywhere.

However we do know that speakers with flat anechoic responses are preferred in mono and stereo. We do know that minor timbral changes caused by rooms and acoustics doesn't change this preference.

So whilst you might be able to argue that some specific eq in a specific situation and listening configuration might be benificial, you can't argue that you should apply a fixed eq to a speaker design. It would never be correct.
 
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Thread Starter #51
No it doesn't because the reflections will be different in every situation and room.
And? The response is dips and peaks resulting from the direct response. Going for the extreme, an anechoic room, the effects will be most pronounced. It will however give effects in most normal rooms. Compensations should be in the range of +/-1 or +/- 1,5 dB in a normally reflecting room and will always be a compromise.
 

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#52
And? The response is dips and peaks resulting from the direct response. Going for the extreme, an anechoic room, the effects will be most pronounced. It will however give effects in most normal rooms. Compensations should be in the range of +/-1 or +/- 1,5 dB in a normally reflecting room and will always be a compromise.
See above.
 
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Thread Starter #53
Well speculate as much as you like but it doesn't really get us anywhere.

However we do know that speakers with flat anechoic responses are preferred in mono and stereo.
Actually, the specific experiments have not been performed or, if they have, not been published.
 

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#54
Actually, the specific experiments have not been performed or, if they have, not been published.
As discussed they have. The preference doesn't change between mono and stereo. You could term it as what the speaker emits into the room is the important factor, not so much the measurement at the listening position.

The futility of trying to define any fixed EQ to be applied to a speaker design has also been explained.
 
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#55
Specific EQ to compensate for the stereo-crosstalk dip will perhaps be a double-edged sword unless you assume that the head and/or the listeners remain in the same exact position at all times. That crosstalk-dip will change when you move your head around and be almost gone when you move off to the sides - where the mono-sound timbre will start to dominate.
The solution to this is sound from reflections filling in the gap, or a center speaker.

@napilopez was pleasantly surprised by the JBL Classic L100 that has this peak around 2k and theorized about that being the cause for his enjoyment of the speaker. Perhaps he can join in here and comment how those speakers sound like when moving out of the main LP.
 
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Thread Starter #56
As discussed they have. The preference doesn't change between mono and stereo. You could term it as what the speaker emits into the room is the important factor, not so much the measurement at the listening position.

The futility of trying to define any fixed EQ to be applied to a speaker design has also been explained.
We are in disagreement here, unless you can link a paper where has been a blind test, Harman style, with a stereo pair, linear in response, and compared to the same speaker, EQed with the specific inverted response of the Shirley curve in the range of +/-1,5 dB.
 

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#57
If I may throw some conjecture into the pool, the effects of the interaural crosstalk on the frequency response is likely to have been compensated for in the mixing and mastering stages given that an equilateral triangle monitoring setup is pretty standard. So compensating for the peaks and dips may actually make the music sound wrong, considering the music was mixed with the presence of these peaks and dips in the monitoring system.
 
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Thread Starter #58
If I may throw some conjecture into the pool, the effects of the interaural crosstalk on the frequency response is likely to have been compensated for in the mixing and mastering stages given that an equilateral triangle monitoring setup is pretty standard. So compensating for the peaks and dips may actually make the music sound wrong, considering the music was mixed with the presence of these peaks and dips in the monitoring system.
If so, why is then a perfectly flat speaker preferred in mono?
 

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#59
We are in disagreement here, unless you can link a paper where has been a blind test, Harman style, with a stereo pair, linear in response, and compared to the same speaker, EQed with the specific inverted response of the Shirley curve in the range of +/-1,5 dB.
The problem is that there is no difinitive curve, there can't be.

Also, what about sounds that are panned left or right? Fully left or right wouldn't require any correction.

You just have to accept that in this respect stereo is a fundamentally flawed system. You can't make an effective correction for the issues it causes, not that they manifest as anything significant from the testing that has been already performed.
 
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#60
If I may throw some conjecture into the pool, the effects of the interaural crosstalk on the frequency response is likely to have been compensated for in the mixing and mastering stages given that an equilateral triangle monitoring setup is pretty standard. So compensating for the peaks and dips may actually make the music sound wrong, considering the music was mixed with the presence of these peaks and dips in the monitoring system.
That's what I also wrote in #3
 
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