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kendomusic
11-30-2010, 04:01 PM
Is a deep null in a fourth order crossover point important? Is it better to have a shallower null and a flatter response? What impact does it have sonically? Just learning.
Thanks
Kendo

dcibel
11-30-2010, 04:16 PM
The reverse-null will always occur, whether it occurs on-axis or not is important.

Looking at the null (when tweeter polarity is reversed) is basically describing the phase alignment at the crossover point. On-axis, if the null is deep and symmetrical you have good phase tracking at and around the crossover frequency. If the null is not symmetrical, it will be reflected in power response as well as a non-linearity.

If you are doing simulations, I'd put more emphasis on the power response than the reverse-null. If you can simulate at various angles other than on-axis, this will give you the best idea of your speaker's performance. It is important to look at the response at all (at least all intended) listening angles. On-axis is just as important as any other axis.

ocdSCHACK
11-30-2010, 08:04 PM
Man, you got hooked to audio fast! I asked the same question(I think.) What I heard for the responses was:
You want to have deep null because it will increase your chances of avoiding any sharp peaks or overpowering frequencies as you move off axis. It seemed that an out of phase speaker may be flat on axis, but you roll the dice with how it will sound in other directions. Again, this is my translation. Having the shallow null might create a peak in another angle. It seems to me like phase would be less important as the slopes get steeper...there is, after all, less interaction between the two speakers (assuming a 2-way.)