Lobing in MTM with TPL-150H and 8PE21

[AllenB]

Ok manninen, because what is needed is a start. Then measure when crossed and adjust.

 

[manninen]

But to make sure right Z values, some drivers are deeper than other.

Like my own project, physical difference between Z value 8-13cm. When measured 35mm seemed to match with Vituixcad.
And measurements where done on same mic positions.

I like to measure simulated crossovers what they are

 

[AllenB]

You can use 35mm if you want, but it is too early to decide if extra delay is wanted. You can even put in a cross without delay for now.

Is it maybe the next stage, just for this speaker, to measure vertical with a cross and the tweeter added, and adjust order and crossover frequency until the vertical polars are good and horizontal as well? This will also tell if the spacing is ok.

 

[LewinskiH01]

Is it maybe the next stage, just for this speaker, to measure vertical with a cross and the tweeter added, and adjust order and crossover frequency until the vertical polars are good and horizontal as well? This will also tell if the spacing is ok.

Sounds like a plan! 2kHz to start with? I doubt it will work well that high vertically.

I'll take a shot tomorrow. Stay tuned (please!! )

 

[LewinskiH01]

Around the crossover, it is basically the same whether TM or MTM.

The problem with LR is its maximum output on axis. This DI discrepancy is normally considered a preferred compromise.

However, add lobing to this and the DI gets larger again. To understand this consider how an odd order crossover handles DI. Furthermore there is now a spectral discrepancy affecting early reflections.

LR and Butterworth are nominal boundaries. I propose that each situation calls for a custom variant.

Allen,

I borrowed the above from the other thread. I hope you don't mind. Not sure what the meaning of "LR and Butterworth are nominal boundaries" is.

I'll go ahead and set a LR2 at 2kHz as a starting point. Let me know if you think there might be a probable better starting point.
FWIW, Acourate has available Butterworth, Linkwitz, Neville-Thiele, LBessel, RBessel, and UB at basically any order. I'll do linear-phase.

Thank you!

 

[AllenB]

LR and Butterworth are nominal boundaries

This means you can choose the amount of phase shift between the drivers.

I'll go ahead and set a LR2 at 2kHz as a starting point.

I don't think you have enough information to do it exactly. You could do a simple crossover on one axis. LR2 at 2k is ok. I think the pattern issues you see will be bigger to look at.