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Old 11-27-2013, 11:52 AM
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Originally Posted by sdurani View Post

You're looking for neutrality that doesn't exist in real life.

Not at all, just trying to isolate variables
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To use Amir's analogy: if you shine a flashlight on a wall, how do you measure the colour of the "wall only"? Not like you can use a flashlight bulb so neutral that it has no colour temperature. And the wall itself isn't going to light up.

It doesn't have to be neutral, you just have to know it's spectral content.

Seems to me by your reasoning you can't measure freq resp of a speaker because there's no such thing as a perfectly neutral mic.

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Old 11-27-2013, 01:41 PM
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Not at all, just trying to isolate variables
How? What type of speaker would you use for the stimulus and what sort of compensation file would use to negate its characteristics?

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Old 11-27-2013, 03:45 PM
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OK, forget issue of how to stimulate the room, as it is not straightforward.

My original intent was to just make the point, seemingly considered rarely, that having a CD speaker does not guarantee that reflections have the same spectral response as the speaker.

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Old 11-27-2013, 05:18 PM
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having a CD speaker does not guarantee that reflections have the same spectral response as the speaker

That's why they (Harman) are trying to design the off axis response of the speaker to exhibit a -smooth- rolloff.
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Old 11-27-2013, 05:34 PM
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Originally Posted by noah katz View Post

My original intent was to just make the point, seemingly considered rarely, that having a CD speaker does not guarantee that reflections have the same spectral response as the speaker.
The input to the system is the speaker. If you start off with a speaker that has really varying response as opposed to on-axis, you make the problem worse. So in that sense, speaker like M2 "guarantee" that whatever coloration you are getting is less than using speakers with worse off axis response.

The transfer function by the way is time dependent. A single impulse will bounce around the room thousands of times before dying. Those reflections combine with the next set and so on. This is at higher frequencies. Below transition you get interference patterns resulting in room modes. Due to high complexity here, we model the impact of the room two ways:

1. Below transition frequency the measurement of the speaker in the room more or less gives you the effect of the room (the room dominates).

2. Above transition frequencies things get very complicated. Yes you can measure them but this will NOT be what you hear. You have two ears which means each one picks up a different signal. The brain then interprets those signals and delivers the final message. No transfer function of the room can tell you these complicated effects. The answers then reside in the realm of listening tests that instruct us on the effect of various walls. The M2's great response by the way is in this domain. At lower frequencies the room dominates per #1.

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Old 11-27-2013, 06:25 PM
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Originally Posted by noah katz View Post

My original intent was to just make the point, seemingly considered rarely, that having a CD speaker does not guarantee that reflections have the same spectral response as the speaker.
Was all this about the word "guarantee"? If so, then I have no problem saying that there's no such thing in this context, any more than the existence of perfection. To that end, why not question whether the C in CD really is absolutely constant?

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Old 11-27-2013, 06:44 PM
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Originally Posted by amirm View Post

The input to the system is the speaker. If you start off with a speaker that has really varying response as opposed to on-axis, you make the problem worse. So in that sense, speaker like M2 "guarantee" that whatever coloration you are getting is less than using speakers with worse off axis response.

Of course; all I'm saying if is that if A (room) x B (speaker) = C (response in room), that when touting the benefits of CD speakers people seem to forget about B.
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Was all this about the word "guarantee"? If so, then I have no problem saying that there's no such thing in this context, any more than the existence of perfection. To that end, why not question whether the C in CD really is absolutely constant?

Yes, more or less.

Not sure why do you bring perfection into it.

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Old 11-27-2013, 08:35 PM
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Yes, more or less.
Remarkable pettiness.
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Not sure why do you bring perfection into it.
An example of a term as non-real-world as guarantee or constant.

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Old 11-28-2013, 01:22 PM
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Remarkable pettiness.

?! Truly, I don't understand.

Seems like I'm failing miserably at communication in both directions, so I'll just quit while I'm behind.

Happy Thanksgiving

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Old 11-28-2013, 01:40 PM
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?! Truly, I don't understand.
Folks use terms like "guarantee", "perfect", "constant" in everyday conversation based on their connotations. Why all of a sudden get hung up on their strictest definitions? Do you see people questioning your use of the word "constant" in the context of CD speakers?

Happy Turkey!

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