If matching dispersion at the crossover point is part of your design criteria, you will need to measure the drivers individually off axis (in as narrow increments as you have time for, 5 degrees is generally sufficient) as well as on axis.
Since the horn height is fairly small, it will loose vertical control at a higher frequency than it's horizontal dispersion.
I'd guess that at 1600 Hz the horn has wider horizontal dispersion (and much wider vertical dispersion) than the woofer.
Are you using both gating and smoothing?
Holmimpulse only lets you choose between raw, smoothed or gated.
Can't combine. The smoothed gets a little too smooth, and as you change the octave scale to get more detail, the reflections creep farther up in frequency.
I prefer the gated on holm impulse.
With nearfield (for bass response), you don't need smoothing or gating.
I guess outdoors is best route. Have not tried it. My measuring setup is not portable, yet.
Your first measurement looks rather similar to my seos12, but with the obvious deeper frequency response.
My off axis measurements are the same as all the other seos12 testers. Falling control at @1.5k.
I measured my woofer as having similar response, so not too bad.
I just looked up the woofer you have. The factory FR looks to have a 2.5db increase starting at 1.5k. Having the larger waveguide might help to cross below that peak. You will need a steep crossover point if you want to crossover higher than 1k. I am having a problem with my woofer's resonance at 1.7k.
I am curious how your woofer measures compared to the factory specs.
Why did you go with such a large waveguide, and smaller woofer?
Have you considered going with a 12" or 15" woofer?
Holmimpulse only lets you choose between raw, smoothed or gated.
Can't combine. The smoothed gets a little too smooth, and as you change the octave scale to get more detail, the reflections creep farther up in frequency.
I prefer the gated on holm impulse.
With nearfield (for bass response), you don't need smoothing or gating.
I guess outdoors is best route. Have not tried it. My measuring setup is not portable, yet.
Your first measurement looks rather similar to my seos12, but with the obvious deeper frequency response.
My off axis measurements are the same as all the other seos12 testers. Falling control at @1.5k.
I measured my woofer as having similar response, so not too bad.
I just looked up the woofer you have. The factory FR looks to have a 2.5db increase starting at 1.5k. Having the larger waveguide might help to cross below that peak. You will need a steep crossover point if you want to crossover higher than 1k. I am having a problem with my woofer's resonance at 1.7k.
I am curious how your woofer measures compared to the factory specs.
Why did you go with such a large waveguide, and smaller woofer?
Have you considered going with a 12" or 15" woofer?
I use a little smoothing on the gated response as well as the non-gated. The resolution is too high (rugged) without it. I went with the SEOS 15, as it was the only one the distributor had in stock at the time
I went with a 10 inch for the smaller form factor. With a 1500-1600hz crossover point it would match directivity of the SEOS-15 (around 100 degrees). I've done measurements and experimented the whole day, only to become more confused... The measurements, and impulse response are extremely sensitive to the slightest changes. Just me changing posture, will drasticly change the response.
I ended up making a XO and EQ configuration by ear, which sounded 10x better then all previous attemts with careful measuring, gating and so on...
I will try to take the speaker outdoors for measurements when summer arrives, and make another attemt the "right way"...
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Try it with ARTA and the technique that Charlie mentions in his tutorial:
http://audio.claub.net/tutorials/FR measurement using ARTA.pdf
-shouldn't cost you anything but some more time.
Try it with ARTA and the technique that Charlie mentions in his tutorial:
http://audio.claub.net/tutorials/FR measurement using ARTA.pdf
-shouldn't cost you anything but some more time.
Thanks, I will look into it
Just purely luck that I went with holmimpulse instead of REW first. I don't have computing power to do both. I am only using the LIMP portion of ARTA right now. Wish I could help you with REW. I have good luck with holmimpulse. When I can upgrade my computer, I would like to have as many programs as possible to compare.
My measurements have been somewhat consistent even when changing rooms. I now know the basic signature of the various speakers and drivers I have. I am sure you will get it all sorted soon.
Have you looked at FR results of other seos15's to compare your results to? I looked at seos12 results to make sure my results were ok. Heck, I even measured in a different room and on a different baffle and got pretty much the same results.
Nothing wrong with doing it by ear. Especially if it sounds better. Many people fine tune passive crossovers by ear.
I would still work with measurements to see what changes you made.
My measurements have been somewhat consistent even when changing rooms. I now know the basic signature of the various speakers and drivers I have. I am sure you will get it all sorted soon.
Have you looked at FR results of other seos15's to compare your results to? I looked at seos12 results to make sure my results were ok. Heck, I even measured in a different room and on a different baffle and got pretty much the same results.
Nothing wrong with doing it by ear. Especially if it sounds better. Many people fine tune passive crossovers by ear.
I would still work with measurements to see what changes you made.
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