Audio: Difference between revisions

There are literally ''tens of billions'' of receivers capable of transmitting audio signals.  This compares quite favourably to the number of [[Bluetooth]] devices.  It would take an overwhelming argument for the absolute necessity of text or video signals to make a service that required them for [[Consumerium buying signal]] desirable.  Historically, one could note that [[industrial radio]] was quite feasible and in wide use before the 1920s, while [[commercial radio]] was in wide use in the 1930s.  However, the addition of [[video]] for [[television]] did not occur in [[developed nation]]s until the 1950s, and the further addition of point-to-point still [[image]] and [[text]] communication wasn't possible until [[fax]] and [[email]] in the 1980s.  And even by the 1990s it was not common to have devices capable of a wide variety of signals.