Originally Posted by
sbm12
That has not been the default for many years now, especially as the 4-conductor model (needed to also have a mic on the wire) isn't an option in 2.5mm.
Also, very irrelevant to the initial query.
There has long been 2.5mm TRRS, otherwise none of the mobile phones would have used it. It is actually still used today for balanced outs in high-end mobile media playback devices.