The first message is a warning, telling you that the horn is so large compared to the cutoff wavelength that the plane wave model is no longer valid. It has always appeared for multisegment horns, when Cir for one or more of the segments exceeds one.
-Bjørn
Hi Oliver,
Brilliant pickup - many thanks!
The error was introduced as a result of making the schematic diagram perfectly symmetrical under all conditions. The problem will be fixed in the next release - likely to be tomorrow.
Kind regards,
David
Hi Andrew,
This should answer most of your questions:
http://audioamateur.com/media/aa/kolbrek2884.pdf
If things are still unclear after reading Bjørn's article, please let me know.
Kind regards,
David
Thanks Brian.
Unfortunately it is another unforeseen undesirable outcome of the recent "improvement" (?) made to the schematic diagram. The problem will be fixed in the next release - now probably tomorrow.
Kind regards,
David
Hi more10,
Despite trying everything that I can think of, I have not been able to reproduce the error you saw.
Are you able to generate the error message again? If so, could you please post details of the specific sequence of actions that causes the message to be displayed. Thanks.
Kind regards,
David
Hi David_Web,
Strictly speaking the radius horn as specified in your example is a valid design. It's just that when the axial length is less than one-eighth of the cutoff frequency wavelength, the radius horn is not really acting effectively, which is why Hornresp displays the warning message on the main input screen and prevents results from being calculated. This same limitation is applied to Le Cléac'h, tractrix, and spherical wave horns.
Kind regards,
David
Hi David_Web,
The result you are seeing is indeed due to the Horn Segment Wizard parameter values being rounded to two decimal places. When the wizard calculates values for anything other than the main input window default configuration, there is always the chance that a subtle change will have to be made to one of those values when "transformed" back to the main screen. This applies to several of the horn types - not just radius horns.
Kind regards,
David
Small changes in BR Fb (like one Hz) also occur between the wizard and the main screen, I'd guess the wizard using only two decimal places would account for that too.
Hi Art,
I assume you are referring to the Loudspeaker Wizard, rather than the Horn Segment Wizard? If so, then this raises a slightly different issue to the one discussed above.
I am not sure why there should be any change to the Helmholtz resonance frequency when Loudspeaker Wizard values are saved back to the main input screen. The slider values in the wizard are to two decimal places, but so are those on the main screen, so the input values used to calculate the Helmholtz frequency should remain the same.
Would it be possible for you to provide screenprints of all the wizard slider settings for an example where the Helmholtz frequency changes when the values are saved back to the main screen? I can then go looking for the reason for the change. Many thanks.
Kind regards,
David
I don't know what that means 
An externally hosted image should be here but it was not working when we last tested it.
but... Thanks David!! 