Schmitt-Walter always sounds like a German baryton-martin, but that's only due to his timbre, not to his vocal range;
after all, his most famous role besides Rossini's Figaro was Don Giovanni. So he was in fact no semi-tenor, and all his
recordings of tenor repertory are transposed.
They're excellent nonetheless; if the librettos of the two Zeller operettas were just not in Tyrolese dialect... Schmitt-Walter,
Rhinelander by birth and
Berliner by decades of professional engagement, had a decidedly un-Tyrolese German diction, and while he maintains an acceptable
level of artificial Tyrolese in the Vogelhändler selection, he's right out of it in the Obersteiger waltz, where his attempts
at singing "Pfiat di Gott" (Tyrolese for bye-bye) arouse pity. But the singing in and of itself is exemplary.
I with to thank Anton Bieber for the Nacht in Venedig recording.
Find Schmitt-Walter in his usual repertory here (scroll down to Tannhäuser).