[Captainhemo]

Or electrically align it with time delay. 

The diffraction pieces on the Neo3 look very interesting.  Looking forward to the horizontal response plot.

hey Rich ,
 in an open config withthe tweeter firing front / rear, if the tweeter isn't aligned  physically with the   woofer voice coil  you could align one side but you'd misaligning the other side by the same amount

jay

[Hafgrim]

I always found that NEO 3 pdr is a nearly perfect tweeter excepted the frequency response.
When I studied the construction, I found that this tweeter sufering of diffraction because of the magnets in front of the diaphragm.

So I've design some flexible resin shape to bond on the tweeter surface (on both side).

This shape cancel the diffraction effect of the tweeter housing

It's 3D printing with formlabs flexible resin:


It's far more effective than I though, nearly perfect response (green curve after modification, red before modification)



I will give up the waveguide! 

Reviving this old post
Has this been discussed more in other posts?
Is there anyone on the forum that can print out a set for me?

[Hobbsmeerkat]

I've done some testing on my own, a couple years ago, and the difference is very small. I even tried different heights to see if i could get a better response, but there wasn't much difference. Smoother in a couple places, but not nearly as drastic as the above results.

The measurements in that graph are most likely near-field measurements, where the round-overs will likely have a larger effect.

In my testing standard testing at 1 meter any differences were quite small, with most changes being +/-2dB happening between 5-5KHz.
When I tested then again in Danny's rig, the differences were even smaller.

The best layout was a tall one in the middle with two round rods.
I probably still have some rods floating around that I can test for more accurate measurements and save the measurements. To share here. Just depends on how long it takes me to find/print more rods our of PLA instead of flexible resin.