Efficient Budget Bookshelf Speakers, Aiy? - Page 2 - AVS Forum
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post #31 of 38 Old 07-02-2013, 10:06 PM - Thread Starter
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Originally Posted by Bill Fitzmaurice View Post

'Decent bass' and 'open baffle' are pretty much mutually exclusive terms. If OB worked all that well no one would waste time, effort and materials building baffled systems.

What are the downsides of open baffle then?
Other than the loss of efficiency and bass output.
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post #32 of 38 Old 07-03-2013, 05:20 AM
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Originally Posted by Mik James View Post

What are the downsides of open baffle then?
Other than the loss of efficiency and bass output.
Isn't that enough?

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post #33 of 38 Old 07-03-2013, 06:03 AM
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With regards to that graph that Arnyk just posted several post back...can someone explain to me what that is and how to interpret it? I see so many measurement graphs posted, but I do t have the slightest clue as to what those graphs are telling me!
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post #34 of 38 Old 07-03-2013, 12:01 PM - Thread Starter
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Originally Posted by Bill Fitzmaurice View Post

Isn't that enough?

Not for me, I'm also interested in learning more about the overall sound quality of open baffle and dipoles. Electrostatics for example are quite popular, and i've heard they also have similar draw backs?
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Originally Posted by Martycool007 View Post

With regards to that graph that Arnyk just posted several post back...can someone explain to me what that is and how to interpret it? I see so many measurement graphs posted, but I do t have the slightest clue as to what those graphs are telling me!

It's a 3d/xyz graph. The numbers on the right are the z/depth axis and represent the angle of the listener to the speakers. The numbers on the left are the y axis and represent the spl. The numbers along the bottom are the x axis and represent the frequency response.
When you put all of the axis together into a 3d image, you can calculate the spl and or frequency response at a given angle on and off axis from the speaker.
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post #35 of 38 Old 07-04-2013, 05:34 AM
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Originally Posted by Mik James View Post

Not for me, I'm also interested in learning more about the overall sound quality of open baffle and dipoles. Electrostatics for example are quite popular, and i've heard they also have similar draw backs?
It's a 3d/xyz graph. The numbers on the right are the z/depth axis and represent the angle of the listener to the speakers. The numbers on the left are the y axis and represent the spl. The numbers along the bottom are the x axis and represent the frequency response.
When you put all of the axis together into a 3d image, you can calculate the spl and or frequency response at a given angle on and off axis from the speaker.

Thanks for that bit of info, Mike. Can you tell me how to tell what the -6db point is on this graph so that I can know and understand how to read the numbers? It looks like you would have to zoom in and really blow this thing up in order to see the -6db point as in its current form I see no way to tell exactly or approx what that point is.

Also, what do you gain by knowing the frequency response is at any given angle? is it useful in predicting peaks and nulls?
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post #36 of 38 Old 07-04-2013, 08:12 AM - Thread Starter
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Originally Posted by Martycool007 View Post

Thanks for that bit of info, Mike. Can you tell me how to tell what the -6db point is on this graph so that I can know and understand how to read the numbers? It looks like you would have to zoom in and really blow this thing up in order to see the -6db point as in its current form I see no way to tell exactly or approx what that point is.

I'm not entirely sure you can get -6db points from this sort of graph accurately. It seems more useful for predicting changes in the response curve.
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Also, what do you gain by knowing the frequency response is at any given angle? is it useful in predicting peaks and nulls?

It will determine the coverage or how wide (and possibly tall?) the listening area is before the frequency response degrades. If your dealing with 2-way (or more) speakers it looks as though it might create a gap in the response as you move further off-axis.
I imagine it would depend on a few other factors though.
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post #37 of 38 Old 07-05-2013, 05:58 AM
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Originally Posted by Mik James View Post

I'm not entirely sure you can get -6db points from this sort of graph accurately. It seems more useful for predicting changes in the response curve.
It will determine the coverage or how wide (and possibly tall?) the listening area is before the frequency response degrades. If your dealing with 2-way (or more) speakers it looks as though it might create a gap in the response as you move further off-axis.
I imagine it would depend on a few other factors though.

So say someone is using REW with a Behringer ECM-8000 calibrated by CSL and a Sound Blaster Live sound card, and a Behringer Xenyx 502 mic pre-amp, how would you go about finding the frequency response of a speaker at any given angle?( I am new to REW so please bear with me!)

Basically what I am trying to figure out is how to properly measure and interpret the graphs for measuring the off-axis frequency response, and polars on a typical 2-way speaker?
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post #38 of 38 Old 07-05-2013, 10:32 AM
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For off axis response, you just place the mic off axis and take another measurement
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