@whitequark✧✦Catherine✦✧ I'm half-surprised it's not the ubiquitous V.8 handshake recording that almost everyone uses for "dialup sounds" these days... (It's missing part of the handshake before the line measurement, so unless they cut that out manually, it's definitely not that recording)
@becomethewaifuEmelia/Emi @whitequark✧✦Catherine✦✧ sounds like it starts with part of a V.8bis handshake - a response tone pair followed by (I'm guessing) CR_d, Es_r, and part of a CL packet. It then abruptly switches to the end of a standard V.8 handshake (a bit of the last CM plus the ending CJ) before entering V.34/V.90 probing/ranging.
Given the abrupt cut between two different protocols as well as the added reverb, I don't know how easy it'd be to demodulate anything from this.
That being said, my gut instinct says this is the same recording used in Oona Räisänen's "The sound of the dialup, pictured" post.
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