As an example, here's 1/3 on the tweeter, 1/6 on the mid, and 1/12 on the woofer
versus zero smoothing:
versus zero smoothing:
It also occured to me just now:
Zero out the driver position in the Y axis. You used a single microphone location for all the measurements I think? If that is true, the Y axis offset is already in your measurements.
Zero out the driver position in the Y axis. You used a single microphone location for all the measurements I think? If that is true, the Y axis offset is already in your measurements.
That polar shows that you are using bad off axis data, so I would ignore anything related to directivity shown here..
Just follow the instructions for VCad2 given by Kimmo:
Perform a dual channel measurement (do not change volume levels between measurements)
if you want a reliable power response, measure each driver on its axis, at least 0-90° every 10-15°
Export the FR in REW according to kimmo's instructions
Design your baffle in Diffraction tool, export diffraction FR at 10m and 1m.
Merge NF and FF responses
Load the all the FRs in main program and set the driver coordinates (Tw is always 0,0,0 and so Zin your case. Yvaries for mid and wf) and start with a template like this: first set filter type and slope and then activate all the PEQ you desire (smooth all the peaks and, possibly, ignore all the dips).
In menu View, select Preference rating > press the button Full space and check the box Show target to get the desired target response: in the picture below the speaker is optimised to get a good PIR
Do I need to enter driver coordinates? And what is modelled if coordinates are not entered?
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@shadowplay62
VCAD beats me every time.
So, I measured in REW off axis response of each driver and loaded into VCAD. I then managed to build crossovers and filters.
Then, in 'diffraction tool' I set the shape of the baffle and add one driver at a time and then export the frequency response one dirver at a time? then murge that with what I measured? but I measured in that very baffle already. Why do I need this step?
I cannot seem to add more than one driver to the baffle in the 'diffraction tool'. Is it one at a time only?
NF and FF merge: of what? FF of mid and tweeter and NF of woofers? In my sim above I used woofers NF but did not do any merge operation, just loaded the FRD on axis into the woofer driver.
VCAD beats me every time.
So, I measured in REW off axis response of each driver and loaded into VCAD. I then managed to build crossovers and filters.
Then, in 'diffraction tool' I set the shape of the baffle and add one driver at a time and then export the frequency response one dirver at a time? then murge that with what I measured? but I measured in that very baffle already. Why do I need this step?
I cannot seem to add more than one driver to the baffle in the 'diffraction tool'. Is it one at a time only?
NF and FF merge: of what? FF of mid and tweeter and NF of woofers? In my sim above I used woofers NF but did not do any merge operation, just loaded the FRD on axis into the woofer driver.
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Why would you use a baffle diffraction tool at this point? Your measurements already include any diffraction. Maybe there's something the software needs, but it doesn't seem logical to me.
I see no reason for using the woofer near field either. But, I'm not up on this software.
I see no reason for using the woofer near field either. But, I'm not up on this software.
You should simulate baffle before making the crossover.
Baffle simulation allows to
- merge nearfield and farfield responses correctly and
- simulate the speaker at any distance different from 1 m (usually 3 m or so)
Yes.
Of any driver that needs frequency response data below the one allowed by gated measurement. Usually woofer and (depending on your reflection free measurement time) midrage.
Tipically, you measure FF at 1m and NF at 5-10mm, then the NF FR does not include the effect of the baffle step loss for Woofer and Midrange.
Prepare all the FRs for W and M and load them in the Merger tool
Once you have all the responses, load them in the main program, set the coordinates for the drivers and calculate your XO.
PS
In the Room tab of the main program it's possible to adjust the listening distance: the program is able to simulate the XO for that distance even if you measured at 1m.