Measurement technology

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Yes, I continually found that the auto scaling function did not always yield what I wanted so now you can adjust it.

I'll change the write-up.

I am thinking of putting a code in the file for "type" like "Two-Way", "Two-Way w/ horn", "Bookshelf" etc. so that the list could be sorted by type. But for this to be effective the number of types has to be limited. I haven't yet found a good set of "types" as there are so many loudspeaker "types". More than 10 types would become not very useful.

This coming week I'll be able to add a brand new JBL 2-way and an older Infinity.
 
On Measuring Loudspeakers PDF said:
Once I have taken all fourteen angular data sets, I export them using File/Export all Measurements (Dialog). Set the “from” point to 100 or 200 and the “to” point to 4800 or more.
That should be negative 100 or 200, right? Here's an attempt for LSR2325P. Distances in the header, let me know if it's useable/etc. and I can do some more. I hadn't used Holm in a long time... P.S. the file is just the txt export as requested - had to zip it to get it to upload.
 

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Cool, thanks for the update and including my data, Earl. Works well here on Win8.

Not to bring the discussion back to ARTA, but I'm comparing my polar data in ARTA to what you have in your Polar Map app. It's interesting that ARTA shows a -6dB of 71° at 2khz with a DI of 4.6dB. Polar Map shows -6dB at what would be 80° total. Same DI. I've always thought the directivity maps in ARTA showed the pattern to be narrower than what I interpret from the set of FR plots. Looking at the FR plots I would say at 2khz the -6dB is closer to 80°, but not quite.

Your app is way cool. It's nice to be able to see all the data that you show on a single screen. I'd be willing to pay to use something like that....
 
Cool, thanks for the update and including my data, Earl. Works well here on Win8.

Not to bring the discussion back to ARTA, but I'm comparing my polar data in ARTA to what you have in your Polar Map app. It's interesting that ARTA shows a -6dB of 71° at 2khz with a DI of 4.6dB. Polar Map shows -6dB at what would be 80° total. Same DI. I've always thought the directivity maps in ARTA showed the pattern to be narrower than what I interpret from the set of FR plots. Looking at the FR plots I would say at 2khz the -6dB is closer to 80°, but not quite.

Your app is way cool. It's nice to be able to see all the data that you show on a single screen. I'd be willing to pay to use something like that....

The -6 dB point depends on what you choose as 0 dB, different choices make different plots. That's why there is an adjustment to what 0 dB is on the plots - to allow for a better match between plots. I believe ARTA scale 0 dB to the maximum point. I scale the mean level in the midrange to be 0 dB that makes them incomparable without adjusting the 0 dB point. (Right click on the main map.)

Why pay to use it when its free? Do you mean to be able to generate your own plots from your own data?

PS. I have no problem discussing ARTA, its personal attacks that have no bearing on the discussion that I abhor.
 
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I never really gave much thought to the 0 dB point, that makes quite a difference. Isn't it a form of normalization? Not to the extent of making it the 0 axis (or whatever axis you choose) of course.

How do we know what is correct here? If I make the on axis response slightly slope down at hf wouldn't that actually widen the pattern on the polar map as the freq increases (using either method of establishing 0dB)?
 
Dump

I added this JBL to the list.
Not bad for an older design, good smooth DI, not that high, but smooth. You probably should boost the 0 dB line about 2 dB to get a good showing of the polars on this because of the strong peak at 10 kHz.

I need to improve the install as it takes too much time. I think that I will allow it to be installed locally, although it will still look to the internet for the database. But at least this way it won't have to be installed each time.
 
Fixed the error above - thanks _Wim_

Also, if it makes any difference, I can handle any spacing of angles as long as there are less than 30 total. I read the angle from the Holm data set. Of course equal spacing is not really the ideal since most of the variation takes place in the forward direction, but maybe people are more used to equal angles.
 
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