SEAS DXT & CA22RNY huge two way with 8 inch midbass & mini waveguide

[superlian]

Seems strange with the dip on one channel at abt 2k in the 1m measurement? Is there some mistake in the XO?

Thats reversed polarity. And thats very good.

 

[superlian]

You need to perform a gated measurement. Your measurement as-is is not really suitable for a crossover simulation.
Then there is that strange 5 dB drop at 10KHz that shouldn't be there, maybe an artifact from the measurement technique?
The measurement with the reversed tweeter shows a relatively poor phase tracking, and a bit too high crossover point.
BTW, in Arta you can save the images, no need to take a photo.

Ralf

I had some challenges with the gating. Will try one more time.

I also thought the 10K drop was an artifact and didnt do any with it.

Please explain a little around phase tracking and how to deal with it?

The reason for the ARTA photo is that it is on another PC who is old and offline 🙂


Thx to all for your answers. I appreciate it very much. I need to learn 😉

 

[giralfino]

The reverse null is too broad and not deep. This is because the phase between the drivers is off (30 deg? 60 deg?). Moreover the response with the reversed driver stays above the “normal” response between 4.5 and 7 KHz, this means that the drivers are out of phase there, so you need to slightly alter the slopes (the woofer is contributing destructively).

Ralf

 

[Rallyfinnen]

Agree, if it is reversed polarity, it should be improved, but it also depends on the mic-position it was taken. I usually have the mic between the centers of the drivers. Having it in tweeter position will get you un-equal distances, that you don't have in the listening position.

For gated measurement in ARTA, you go to IMP, select the window you want to use (I think it's left and right clicks), and then up in the View-menu you select to calculate the gated smoothed FR or something like that. It's all somewhere in the ARTA manual 🙂

 

[superlian]

Thx for good advices so far 👍

 

[superlian]

I did FRD measurements of the DXT tweeter again to check if my procedure is corret.

Yellow is 1 mm from the protection mesh. Green is 1 meter on axis between DXT and the CA22RNY woofer. I use 20uF capasitor as a protection:

Then i convert the green measurement to impulse response:

And save the last as a ascii tct file. FRD doesnt come up as an option.

 

[Ro808]

They certainly look great. Love the dark grey.

My only concern is the 4db frequency response drop from 200hz to 20khz.

Love dark grey too 😉

What's wrong with the drop?