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Perhaps this type of measurement cannot be done accurately outside of an anechoic chamber. Some of those measurements seem to defy logic.Thank you for your effort!
I have three kits out that use coaxial drivers.
Pardon me for being dense, but I went to your products page and could not find any kits that utilise coaxial mounted tweeters.
Mr. RennoVattio, This is what I do for a living and full time for the last 12 years. I have been there done that and had a full sized anechoic chamber of my own. I have worked with and looked at these applications many times. What I showed you in those measurements is EXACTLY what happens every time without question. Most implementations like this that I have seen (using a larger diameter woofer) look MUCH worse. Here is a commercial speaker that I measured for a magazine review: http://www.stereomojo.com/Sequerra%20MET%207%20MK6%20Speaker%20Review/SequerraMet7.7Mk6review.htmIt allowed the woofer to play full range and was augmented by a tweeter with a single cap and an adjustable resistor value. Have a good look at the measurements and details regarding how they were measured.
So I guess it stands to reason to presume then that whether chamber or room, it will be similar "without question", which implies that room reflections make a negligible difference. That's refreshing.
I am curious about what you think of 1st order cross-overs in general. I see why they do not work with wide-band drivers(facing forwards anyway), but what about with drivers that have a lower natural roll-off. There are manufacturers that like to promote the idea of 1st order cross-overs being superior because they are in phase.
I have only heard a couple of wide-band drivers, but to my ears their flaws are not just the lack of high end extension. I think the smaller ribbon/tweeter may just move faster and be more accurate through an important range of frequencies. Or perhaps, it has more to do with an improved off-axis response.
Since the woofer is only a 3 inch woofer right at the top of the box then it is not near as bad as a larger diameter woofer with the tweeter much further away.
Listening off axis on a larger woofer would have much less top end and have a low pass effect and would not be as bad.
No, it's worse.Changing the vertical listening or measuring axis 10 degrees or so will not allow the larger driver to roll off that much, but in comparison the phase rotation is greater due to the acoustic centers being much further apart. The same movement of distance creates a greater amount of delay with the greater acoustic center distance.
At about 30 degrees off axis, listening to my 8" without ribbon tweeters there is a definite drop off in high frequencies. Adding the tweeter brings the top end back and the system sounds balanced, very good, very immediate and alive unlike conventional common 2-ways.
I cannot comment on whether this sounds "worse" than your setup with a 3" with a ribbon.
Try listen to an 8" setup with real music, 30 degrees off axis and report back.
The 6.5" driver I use has near zero response at 11.8K, the roll off being dramatic. Perhaps you could retest with the smaller capacitor value and a low frequency driver without energy in the top octave.
The last one that I posted measurements of had a pretty rolled off top octave and I only used a .56uF cap on the tweeter circuit. You are welcome to send your speaker over for measuring. Just cover the shipping cost and I'll measure it all for you.
