[bwann]

The key is to use a non-compressed codec such as G.711u/a-law, and disable echo and silence suppression. I can regularly get 28.8k-33.6k carrier speeds across the US when using an ITSP/VoIP provider and my modems connected to Grandstream/Linksys/Cisco analog telephone adapters.

[wat10000]

I have to ask, why are you regularly using dialup over VoIP across the US?

[bwann]

Vintage bulletin boards and running a retro UUCP network

[estimator7292]

There's a certain subculture who enjoys connecting machines to the modern internet which have absolutely no business being on the modern internet, and thus only have modems.

Dreamcast Quake 2 matches were one of the most popular uses last I checked