eigenmode frequencies

[GM]

hello all,does anybody know if having a mid or high frequency horn driver combo in the throat/mouth area of the 816 series of mid bass enclosure would cancel any effect of the eigenmodes of the affected frequencies in the enclosures passband? this is in reference to the two parallel surfaces that are part of the wooden horn flare.thanks in advance.

The bass horn's eigenmodes will still be there, just at differing amplitudes plus the HF horn will be acting as a crude phase plug which will add a bunch of new ones, but 'chopped up' [much more random, AKA higher order modes], so actually smooths it out somewhat at the expense of a small loss in output due to less horn volume [Vb].

For HIFI apps, adding an open cell foam plug [after Dr. Geddes] will smooth it out further. IIRC he uses 30 ppi.

GM