Depends on what frequency range you call midrange. I am currently working on cone driver horn to run 500Hz to 3.5kHz with wide horizontal dispersion. Its mating lo-mid horn will be bent (ie not abruptly folded) and run from 150Hz to 500Hz. Unless you want to cover wide band and down fairly low, path length is quite often too short to allow folding due to the large radius bends required to path the higher frequencies. A wide band folded horn will also beam quite significantly at high frequencies."Wood sound in voices" would suggest to me improper horn and/or crossover / component selection.
Cheers