Soundwave theory question: reflection
 

Hi, is anyone able to help me grasp a particular question please.

If a 300mm (1 foot) diameter column is pressed up against the front of a loudspeaker (or just clear) ----

1--- which wavelengths reflect straight back to the speaker?

2--- which wavelengths are scattered widely?

3--- which wavelengths are relatively unaffected and pass right around the column?

4--- is there a transition region between 2 and 3 and if so, what happens in it?

I would like to better understand the relationship between deflector size and sound wave behaviour.

Thank you

How big is the driver?
There is open source software to model this at
AcouSTO - Acoustics Simulation TOol - Homepage
but not easy to use

Well it is an in-principle question, so I will take any driver size you care to assume. thanks

I haven't seen that tool before. I will take a look.

Any generalised answers would also be much appreciated.

I think you will find that this is much easier to measure than calculate, and it depends on your observation point. Probably the best way to resolve this qualitatively is with a java ripple simulation calculator - do a search.

Thanks Ron, I'll have a look.

I wonder if there is a general rule like "if the wavelength is more than twice the column diameter, there is little to no scatter of the sound"?

The behaviour of a plane wave passing your column is fairly easy to predict. You have a far more complex situation as the column is close to the source and gives early reflection back to the driver

It's probably closer to 6 times...

Thanks Ron and David, I will continue to study it.

Would a Hornresp simulation throw out anything useful?