Played around outside today….. Here’s a little idea for you. First everything with delay and after that no delay only 2nd order all pass filters.
I’m done for today but if i have time i might add some more to this post. For now just a couple of pictures 😉 Enjoy
Timo's World all around the globe 
It will great to have some instructions Goin on in captions.
Thank you Timo.
I would if i had time for it so sorry but that will not happen on this capture. If you know the basic idea on a front-back config and an end fired array: this is a mix between the 2