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Multi-Way Conventional loudspeakers with crossovers

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Old 29th July 2011, 04:30 PM   #5421
doug20 is offline doug20  United States
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Awesome, that gives me a great comparison!!

thx!
Doug
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Old 29th July 2011, 04:42 PM   #5422
gedlee is offline gedlee  United States
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Quote:
Originally Posted by dlr View Post
I understand you position and agree for the most part, but there are issues with drivers that are polar in nature and can to some degree be improved on a polar basis. I would posit a spider resonance as an example. This is seen at most angles of a direct radiator. It can be improved in a way that improves most, if not all axes. But yes, the polar response must be considered in its entirety.

Dave
This is why being able to "read" polar maps is so useful. If the aberation you are trying to correct is constant along a vertical line, like a mechanical reonance in the driver, as you suggest, then EQ is effective. But if it is diffraction or acoustical modal related then it will be different at every angle and correcting one angle will inherently make all the others worse.

You have to understand what it is that you are trying to correct and "black box" global solutions can't do that.

There are some aberations in my speakers for which EQ can correct - such as a spider resonance - and others for which EQ has no hope of correcting, like the axial response dip from the mouth diffraction.
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Old 29th July 2011, 05:17 PM   #5423
badman is offline badman  United States
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My own waveguided Heil AMT

Hornloading the Heil AMT1
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Old 29th July 2011, 05:56 PM   #5424
soongsc is offline soongsc  Taiwan
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Talk about directivity and CSD, here is a different data set measured at 0 and 30 deg.
Click the image to open in full size.
Not really sure to what measurement the eq was based on. But the match of 0 and 30deg SPL is quite unexpected.
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Old 29th July 2011, 07:00 PM   #5425
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Originally Posted by Patrick Bateman View Post
Comparing a direct radiator to a driver on a waveguide is semi-pointless; the direct radiator will always be cleaner. It's like comparing acceleration figures for a bicycle and a car.
I don't understand. Both are meant for sound reproduction.

Nor do I get the analogy; which is which?
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Old 29th July 2011, 07:02 PM   #5426
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Is the one with UE supposed to be better?

From what I can see, the resonances are somewhat narrower but with longer decay times.

Quote:
Originally Posted by soongsc View Post
The raw driver would look like this.
Click the image to open in full size.
Then in active speaker with Ultimate Equalizer
Click the image to open in full size.
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Old 30th July 2011, 12:04 AM   #5427
soongsc is offline soongsc  Taiwan
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Originally Posted by noah katz View Post
Is the one with UE supposed to be better?

From what I can see, the resonances are somewhat narrower but with longer decay times.
That's where you have to make a decision by listening. Measurements are sometimes effected by things we do not have total control of. I was asked to turn off UE during the show to see what happens, and the comment was "it still sounds good". For me, the UEed one sounded better. Is it the ultimate end? Not by a long range. The fun is in the journey to see what one can actually do to make changes that show up as improvements both technically and through listening.
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Old 30th July 2011, 11:02 PM   #5428
doug20 is offline doug20  United States
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Quote:
Originally Posted by noah katz View Post
Is the one with UE supposed to be better?

From what I can see, the resonances are somewhat narrower but with longer decay times.
They look like inaudible decay though, when the FR is 80dB and the first ripply is below 50dB Im not going to be concerned and over 18Khz is meaningless to me too. The 1Khz to 5Khz region is what I see has a huge improvement, the 2nd one (EQed, linear phase) looks to me like the "cleanest" sounding tweeter possible. I like that sort of sound (hence why I like Ribbons).

Last edited by doug20; 30th July 2011 at 11:06 PM.
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Old 31st July 2011, 02:05 AM   #5429
soongsc is offline soongsc  Taiwan
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Actually, it's a small full range driver. Trying to get that 20kHz breakup under control took great efforts, and work is still going on to see if there is any way to redesign the driver for better performance.
The fast initial decay gets critical when loud playing occurs. For example, if the music is at 85db and you can get it to drop below 60db very fast, then this part of the system has little effect in sound coloration, and the room becomes dominant.
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Old 1st August 2011, 06:07 PM   #5430
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I guess I wasn't looking at them correctly.

I was looking at the tail end timewise, where the mounds look bigger, failing to note the fast initial decay.

I find these difficult to read; shouldn't the color correspond to dB?

You can count the lines to figure out the time, but it's hard to tell the level because of the 3Dness.
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