Passive Crossover for Beyma TPL-150H

Below is a great passive crossover schematic for the Beyma TPL-150H.  This is a simple crossover that deals with the midrange hump in the raw frequency response.  Otherwise the driver will sound harsh and forward.  There is excellent treble detail waiting to be revealed if the crossover is able to flatten the response in the midrange allowing the treble to come through.  This is an Air Motion Transformer after all, so it should have world class treble.  If you have this driver and feel that it isn't quite up to par to all the hype and reviews, then perhaps you need to look at your crossover design and make some changes. 

Here is the raw frequency response of the Beyma TPL-150H as measured in REW. 

Beyma TPL-150H raw response @1meter

Below is the response comparison with my passive crossover that I've developed...

Frequency Response Comparison between raw response and with Passive Crossover.

Here is the schematic for my crossover...
As you can see it is a simple crossover.  I like the treble lifted slightly when listing to this driver.
The reason for this is that slightly off axis things flatten out so the averaged response will actually sum to flat in terms of the on and off axis response.  To show this here is the response 15 degrees off axis...
If you find that there is a little too much high treble you can adjust the resistor to a lower value.  By dropping the 22 ohm resistor to 10 ohm we the following response...

Comparison between 10 and 22 ohm resistor (purple 10, brown 22)

As you can see you get another 5dB of senstivity when switching to the 10 ohm resistor.  Since I'm using a 12" woofer rated at 95 dB@1watt then this will likely be more suitable for my setup. 
You can experiment with different value resistors to custom tailor the overall response curve to your subjective liking.   For example you could order 10,12,15,18, and 22 just to experiment.  Resistors are only a few dollars so why not? 

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Originally published at Crowe Audio.