From an article about analog vs digital recordings, where I found this bit about telephone band practice

Here’s one bit of historical trivia: Even the earliest connections in the 1920s were so continuously lifelike that musicians who had access to shared “party” lines would often practice music over the phone, rather than travel to each other’s houses.

https://www.fairobserver.com/more/science/neil-young-vinyl-lp-records-digital-audio-science-news-william-softky-39078/