Alveolar Non-sibilant and Tapped Fricatives

[TurkeySloth]

As [θ̠, ɾ̞̊, ð̠, ɾ̞] are allophones of other sounds in natlangs, I expect some variance in their pronunciation. But, [ð̠, ɾ̞] sound [ʒ]-like to me, whereas I expected [ð̠] to sound [d]-like. Are [ð̠, ɾ̞], actually, that similar, or is [ð̠]'s clip incorrect? If the former, why?

[Tropylium]

The exact POA is hard to tell from these clips, but they're very clearly apical fricatives. The laminal equivalents (as used in Icelandic) are much more similar to usual dental [θ ð].

The notion of "tapped fricative" is new to me and, frankly, sounds nonsensical. The voiced example here seems to be a fricative trill.

[anteallach]

The [θ̠] sounds OK to me; the [ð̠] does indeed sound a bit too sibilant and perhaps a bit too retracted for an alveolar.

The [θ̠] I have in my English (variable allophone of /t/ in intervocalic position) is definitely apical, and perhaps slightly postalveolar.

[TurkeySloth]

The exact POA is hard to tell from these clips, but they're very clearly apical fricatives. The laminal equivalents (as used in Icelandic) are much more similar to usual dental [θ ð].

The notion of "tapped fricative" is new to me and, frankly, sounds nonsensical. The voiced example here seems to be a fricative trill.

Wikipedia describes taps, including fricatives, as "having a single contact" and trills as "ranging from one to three contacts." Thus, any tapped fricative could be considered a fricative trill.