Hi
I mounted a tweeter "dayton-audio-ND25FA" once in a test box where i tested the mid and one in the final box design. (the test box was intended to the the mid only but i mounted the tweeter to get an idea of how this speaker will sound)
See attached measurements and images.
in the test box it case a and in the final box it is case b.
in the measurements the orange is the test box (case b)
Case B looks very bad. but it does not look like baffle diffraction loss.
just a note on the image you see with the final box:
it is on a shelf close to the wall because i want the destine the xo with measurement of how this unit will be placed when it is ready.
when removing the shelf it did not to any effect on the tweeter measurement (as expected i guess)
Thanks
Ran
I mounted a tweeter "dayton-audio-ND25FA" once in a test box where i tested the mid and one in the final box design. (the test box was intended to the the mid only but i mounted the tweeter to get an idea of how this speaker will sound)
See attached measurements and images.
in the test box it case a and in the final box it is case b.
in the measurements the orange is the test box (case b)
Case B looks very bad. but it does not look like baffle diffraction loss.
just a note on the image you see with the final box:
it is on a shelf close to the wall because i want the destine the xo with measurement of how this unit will be placed when it is ready.
when removing the shelf it did not to any effect on the tweeter measurement (as expected i guess)
Thanks
Ran
Attachments
The amplitude in the measurement case a ves case b:
They were not measured at the same day and not at the same volume.
I shifted one on the measure in order for them feet at the low frequencies.
They were not measured at the same day and not at the same volume.
I shifted one on the measure in order for them feet at the low frequencies.
so what is baffle diffraction supposed to look like?
and there's a big difference between the "test" situation and the "final" with respect to additional surface area around the tweeter, then add the distance to boundaries i.e. the test case(free space) versus the "final" (against a wall).
but if your looking for other possibilities the only thing i would look at is x-over summation.
and there's a big difference between the "test" situation and the "final" with respect to additional surface area around the tweeter, then add the distance to boundaries i.e. the test case(free space) versus the "final" (against a wall).
but if your looking for other possibilities the only thing i would look at is x-over summation.
Often you will see a rise just above the fall. You could measure at different angles and average.
I don't know if your measure is gated or not, but I suppose isn't. If so repeat with a necessary gate.
Looking at the manufacturer's datasheet, taking into account the very different grid between yours and manufacturer measures, probably your measure B is how it is supposed to do, and the effect you see could be simply the effect of a non damped resonance. Maybe the resonance of your tweeter is higher than specs at around 2KHz, if possible measure impedance too.
Ralf
Looking at the manufacturer's datasheet, taking into account the very different grid between yours and manufacturer measures, probably your measure B is how it is supposed to do, and the effect you see could be simply the effect of a non damped resonance. Maybe the resonance of your tweeter is higher than specs at around 2KHz, if possible measure impedance too.
Ralf
I'm not sure I'm reading this correctly, but to me this looks like purely boundary reinforcement.
Move the speaker out to the middle of the room and re-test.
This, BTW, is why for 2-way systems I measure the mid-woofer in place, not quasi-anechoically.
Move the speaker out to the middle of the room and re-test.
This, BTW, is why for 2-way systems I measure the mid-woofer in place, not quasi-anechoically.