For many centuries, the salpinx held its position as announcer in the Greek games or agon. Eventually, in 396 BCE, we know that its position was recognised by the instigation of a contest to decide which salpinktes (salpinx player) would officiate throughout the games. it was clearly an important position as the introduction of the contest indicated. despite this, many authors still refer to the salpinx as a military instrument or ‘war trumpet’.
When the Greek lands were over-run by the Roman hoards, unlike what happened in Etruria where the Etruscan civilisation was systematically wiped out, the Romans embraced Greek culture and the games or agon continued. Eventually, the Roman ruler Diolcletion set up, in 62 CE a Roman version of the Greek Games which he called the Capitolia. In this, the role of the salpintes and his salpinx was retained but Roman references to this are made in Latin and thus he became, to the east of the linguistic Iron Curtain, a tubicen blowing a tuba. However, whatever he or his instrument were called, the function of the signalling brass was continued.
However, Greek civilisation had deep roots and the salpinx had retained many associations with brass instruments which had been used many centuries and possibly even millenia before. Such cultural associations may well have been the reason why the salpinx remained largely unchanged throughout the many centuries of its use in the games. Just why these associations weakened with the onset of Roman rule cannot be ascertained but it seems that, in the Romanised version of the Greek agon/games, the salpinx, on becoming the tuba, was freed from earlier restraints and began to be seen in a different light. This new view appears to have regarded it much more as an instrument with musical potential rather than one which gained its power from the earlier associations and this allowed it to be used in more of an art-music context and for it to be developed to perform better in this role.
I have discussed this process in a longer paper/article on this site which may be found here: http://hornandtrumpet.com/papers/2023-05-the-war-trumpet