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Discussion Starter #1
I bought both these drivers to test and use the more appropriate one for my install. I wanted to see how the two compared so I did some testing. I do not have HD data on these, but to be honest, I don't need it. Either driver will be crossed above 3khz where distortion should be a non-issue. Additionally, I fear blowing them testing them at high levels, so I didn't...
I might try to revisit this later using a filter in foobar to generate a bandpassed sweep in order to protect the drivers if I have the time. Until then, FR data is all I have along with some cool polars.

Comparison time...

The following test was done with Dayton's Omnimic system. Thanks to Madisound for the special driver testing pricing!



First off, mfg info:
D2004:
ScanSpeak Illuminator D2004/6020-00 Tweeter: Madisound Speaker Store

R2004:
ScanSpeak Illuminator R2004/6020 Tweeter Small Ring Radiator: Madisound Speaker Store


IMPEDANCE AND T/S:


D2004 Impedance:


R2004 Impedance:


FREQUENCY RESPONSE:
Frequency Response of the D2004 at 0, 30, and 60 degrees:


Frequency Response of the R2004 at 0, 30, and 60 degrees:


POLARS FROM 0 TO 60 DEGREES:

D2004:



R2004:


COMPARISON IN FREQUENCY RESPONSE BETWEEN D2004 AND R2004:

Note: The Ring Radiator version is less sensitive than the Dome (d2004) by about 1dB, so to make it easy, the RR is always the graph below the top graph.


0 Degrees:


30 Degrees:


60 Degrees:
 

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Discussion Starter #3 (Edited)
What this shows me is something I had pretty much always thought: while a dome may have better response up high off-axis, the RR has a much smoother response and still isn't terribly bad off axis. In fact, the difference at 13khz is roughly only 3dB at 30 and 60 degrees after accounting for sensitivity.

This is the reason I provided the data the way I did. I wanted to see and show how the off axis response of these drivers differed. I think this may make some think twice before automatically discounting a RR based on the notion it can't perform well off axis.
 

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I had the R's in my truck... They were spectacular! I had them somewhat off axis in my pillars....They did sound better the more on axis they were.....However they did not make it through the truck fire:(
 

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So the dome has the better dispersion. It's true that the difference isn't huge.

It's not clear to me why you think HD doesn't matter when you cross a 3/4" dome at 3khz. Most oversized tweeters running 2.5khz in a car struggle at medium to high output, these are much smaller.

If you think HD is not an issue you should probably compare the 1" RR vs. the 3/4" dome that way at least you keep the tweeter SD closer. Then the dome will spank even more.

I think the RR is good to look at but the dome will kick it's ass all things equal.
 

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Discussion Starter #7 (Edited)
Well, I don't mean to make it sound trivial. I'm just basing the assumption of Zaph's test of the 1" and other 3/4" drivers (scan). Im making the assumption they still perform well in this regard like their predecessors.
I'm not saying its nothing to worry about at all. I just don't see it being an issue and I didn't want to risk frying one until I can high pass them. Kind of like how you disable your tweeters for your high output HD testing in your "test bin" thread.

This testing was done for myself. The fact that it's posted is an afterthought. Once I can get foobar to play nice I'll do some HD testing with a HPF that gives enough information to be useful but still protect the drivers.
 

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A quote from Zaph:

"The most important criteria in selecting a tweeter is the harmonic distortion on the low end near the crossover point. This is the most audible defining characteristic of a tweeter, more so than top octave frequency response. System power response, while critical at the crossover point, becomes a non-issue higher in frequency. This is simply because the room plays less of a roll in the reflection of high frequencies back to the listening position. There is a lot of high frequency absorbtion in typical room construction, and even painted drywall almost completely absorbs a 15kHz tone. So, as I mentioned above, if you can toe in a system using a larger tweeter, all is well.

If this article sounds a little biased against 3/4" dome tweeters, that's because it is. In most cases, I see absolutely no reason to use a 3/4" tweeter, particularly with larger woofers. The only 3/4" tweeters I've used on this web site were selected based on cost and the fact that the mid/woofer used with it was small and had a very extended response. Maybe someday someone will create a 3/4" dome that can hang with the 1" boys at the low end, but for now it doesn't exist. "

I couldn't find the 3/4" test on his site, if they look the same as the 1" that would invalidate his stance.

I disconnected my tweeters because there was no need for a test of 110db and up on a supertweeter. There is a lot less content over 6,3khz and it matters very little for distortion measurements. If you cross yours at 3khz distortion will matter a bunch more imo. I also have plots of them playing up to 105db so the difference was not between no plots and some.
 

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Discussion Starter #9
Yes, I'm aware of the cruciality of the 1-3khz range (I actually propose 1-4khz due to the ear sensitivity issue in this band).
Again, this test was done for myself and posting it was an afterthought. In the passband I'm running these tweeters "above 3khz" distortion isn't a concern (coupled with what I already know about how most drivers test in this region and the caliber of component Scan puts out) so I didn't perform the test. But, I absolutely agree that distortion in this band is critical. If I were going to cross below 3khz then I'd have been more adamant about getting distortion figures.

That said, I'll have some distortion plots up sometime tomorrow. I finally got foobar working but I also just put my daughter to sleep. I don't want to wake her back up. ;)
 

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About that, scan rates the 3/4 dome at .4 xmax, 100% more than the 1", and 400% more than the vifa ne!
 

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Discussion Starter #11
100% more than the 1" dome or 1" RR? If it's the dome... damn! Wonder what's up with that.


I really want to put these on the klippel. But, I really don't want to burn 'em up. I need to get some cheapo tweeters to test on the klippel to get familiar with the protection settings (ie: what works best power wise). I'm thinking no more than a couple watts would get you the data you need but this isn't like a woofer where you have suspension to help keep you in check. You've got the VC on the tweeter and there's not much there to really help you if there's overshoot in the measurement... and the Klippel is liable to kick out a few extra dB in response instantaneously. :/
 

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100% more than the 1" dome or 1" RR? If it's the dome... damn! Wonder what's up with that.


I really want to put these on the klippel. But, I really don't want to burn 'em up. I need to get some cheapo tweeters to test on the klippel to get familiar with the protection settings (ie: what works best power wise). I'm thinking no more than a couple watts would get you the data you need but this isn't like a woofer where you have suspension to help keep you in check. You've got the VC on the tweeter and there's not much there to really help you if there's overshoot in the measurement... and the Klippel is liable to kick out a few extra dB in response instantaneously. :/
I liked what the Danish guy recommended before you started testing. Set a hefty HP filter, say 2,000hz. The scan coils are rated at 120ish w at 3,000hz and up so at 2,000hz I'm sure they are very good for 10w and that's probably more than you will need. I would think Klippeling a tweeter versus a subwoofer is only a matter of precision. Both of them should have xmech a lot greater than xmax and enough coil to show linear operation.

It seems that all Illuminator 3/4" tweeters have .4mm of xmax claimed whereas the 1" have half of that, .2mm. Makes you wonder if Scan really did try to make these 3/4" as low distortion as the 1" but with better dispersion. One can dream right? :) The xmech is the same so given the smaller area on teh 3/4" you still can't reach as high of a peak SPL but linear output should be similar and that's fantastic.

I'm loving the polar plots but I'm not sure I could make them useful. You use that protractor thing to make sure the degrees are accurate right? I don't have anything of that sort to use in a car.
 

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Yep. I've listened to both. They sound like tweeters.

The measurements tell you more than that, though.
I HATE when tweeters sound like tweeters. ;)

I like how the Omnimic setup works BTW. Polar response is pretty cool too. Do you mind confirming I'm looking at it right? Vertical is frequency response, center is 0 degrees (i.e. on-axis), far left and right is 60 degrees, color represents DB drop. The red in the center matches the on-axis rise of both drivers from around 5khz to 10khz. What has me confused is that 10khz+ shows purple (15db) when your FR plot only shows a slow 6db or so drop for on-axis.
 

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Yep. I've listened to both. They sound like tweeters.

The measurements tell you more than that, though.
So you have more faith in the testing equipment than your ears when comparing tweeters? :laugh:
if all tweeters sound like tweeters, you should stop spending money on scan speak and buy tang band or something else cheap. :rolleyes:
 

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So you have more faith in the testing equipment than your ears when comparing tweeters? :laugh:
if all tweeters sound like tweeters, you should stop spending money on scan speak and buy tang band or something else cheap. :rolleyes:
You laugh but that's not a healthy laugh. The freedom of speech you enjoy on the internet is as rewarding as it is pernicious. It is rewarding when someone goes out of their way to provide useful testing for your own good and it is pernicious when you show up on your thread just to slander and ridicule.

If you have so much faith in your ears how about you make your own thread. Tell me at every frequency 900hz and up and up to 15degrees of axis what your ear dictates polar response to be. That's nearly 300,000 data points. When you are done do it again for the second tweeter. Wrap it up in a nice graph color coded to show degrees so I can grasp it in a few glances.

I believe Erin's point is that sometimes performance is so small between a good company's top choices that they may appear equal to one's hearing. A precision tool can pick up the subtle differences when an ear might not. The added benefit of these types of tests then is that you get to pick the better performing tweeter despite the fact that you couldn't do otherwise with more rudimentary approaches. There is also something to be said about the vast array of performance outcomes these tests give you, again think 300,000 head positions.

I personally would have no problem buying a TB unit that outperforms a Scan Speak. That is however unlikely, Scan's products are so well optimized compared to the TB units it's hardly a contest. This is evidence in itself that they are using high end technology in development.

Asking someone to drop years of training for rudimentary approaches is like asking your car mechanic to diagnose not by using an obd2 scanner but by feel, or a heart surgeon to treat stroke patients with tea leaves.
 

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You laugh but that's not a healthy laugh. The freedom of speech you enjoy on the internet is as rewarding as it is pernicious. It is rewarding when someone goes out of their way to provide useful testing for your own good and it is pernicious when you show up on your thread just to slander and ridicule.

If you have so much faith in your ears how about you make your own thread. Tell me at every frequency 900hz and up and up to 15degrees of axis what your ear dictates polar response to be. That's nearly 300,000 data points. When you are done do it again for the second tweeter. Wrap it up in a nice graph color coded to show degrees so I can grasp it in a few glances.

I believe Erin's point is that sometimes performance is so small between a good company's top choices that they may appear equal to one's hearing. A precision tool can pick up the subtle differences when an ear might not. The added benefit of these types of tests then is that you get to pick the better performing tweeter despite the fact that you couldn't do otherwise with more rudimentary approaches. There is also something to be said about the vast array of performance outcomes these tests give you, again think 300,000 head positions.

I personally would have no problem buying a TB unit that outperforms a Scan Speak. That is however unlikely, Scan's products are so well optimized compared to the TB units it's hardly a contest. This is evidence in itself that they are using high end technology in development.

Asking someone to drop years of training for rudimentary approaches is like asking your car mechanic to diagnose not by using an obd2 scanner but by feel, or a heart surgeon to treat stroke patients with tea leaves.
I appreciate the data provided by thread starter, but in the end it is what my ears hear that matters to me, and hopefully everyone else at this forum. If you get to hung up in what you measure, you might not get the best product. That is why I asked if he had listened to them, but open your eyes and ears guys. in the end, it is how everything sound that matter?!
And seriously, if you cant hear difference in tweeters, (ref: "Yep. I've listened to both. They sound like tweeters.") you shouldn't bother using all your money on scan speak. This was an advice more than rudeness.
 

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I appreciate the data provided by thread starter, but in the end it is what my ears hear that matters to me, and hopefully everyone else at this forum. If you get to hung up in what you measure, you might not get the best product. That is why I asked if he had listened to them, but open your eyes and ears guys. in the end, it is how everything sound that matter?!
And seriously, if you cant hear difference in tweeters, (ref: "Yep. I've listened to both. They sound like tweeters.") you shouldn't bother using all your money on scan speak. This was an advice more than rudeness.
I got planar speakers to sound like a line array of pro audio cones. Certainly it wasn't a triumph of by ear tuning. It took careful bandpassing to put both speakers outside of trouble nonlinear distortion regions. Output matching, and tuning both to a desired curve. I could just as well say speakers are speakers. Note however just how much work goes into sectioning the output just so, and how you really can't do this by ear. It's just not fine enough of an instrument. I can switch back and forth between the custom EQ. curve and no EQ. and my ears tell me there is a definite improvement tuned but no way in heck I could have gotten those EQ. settings by ear.

We all care how it sounds to us. It's not like a mic automatically results in some abstract tune that has no tangency with reality, quite the opposite. I should also remind you that we all still have ears, i haven't chopped mine off and put mics there instead. I can easily change to by ear tuning but why? It's just regression...
 

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Note however just how much work goes into sectioning the output just so, and how you really can't do this by ear. It's just not fine enough of an instrument. I can switch back and forth between the custom EQ. curve and no EQ. and my ears tell me there is a definite improvement tuned but no way in heck I could have gotten those EQ. settings by ear.

We all care how it sounds to us. It's not like a mic automatically results in some abstract tune that has no tangency with reality, quite the opposite. I should also remind you that we all still have ears, i haven't chopped mine off and put mics there instead. I can easily change to by ear tuning but why? It's just regression...
The winner of EMMA advanced unlimited this year, Joachim. His car is tuned by ears and so could you.
Mics and measuring equipment is good tool to use finding errors and such. But yet again, sound perception is not just acoustics but also just as much Psychoacoustics. your measuring gear cant measure how you perceive music. So yes, tools are great but in the end; TRUST YOUR EARS!
 
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