Changes to Orchestra tuning.

I've never heard an Oboe give the reference. Always the 1st Violin. Am I missing something?

Yes.  

Don’t know what orchestra concerts you have attended, but the oboe always gives the tuning reference in an orchestra.  The oboe sometimes gives two tuning “A440-445”s (or whatever).  One for the winds and then one for the strings.  When it is a piano concerto the tuning reference “A” is taken from the piano on stage by the oboe and then as above.  Only when there is no oboe, in a chamber work for instance, does the first violin give it.  

@frogman Question: why the oboe in particular?

@simao , long standing tradition due to the oboe’s piercing tone which can be clearly heard and the fact that the oboe does not have an easy way to adjust its own pitch, unlike other instruments which have tuning slides or parts that can be adjusted to make longer or shorter.  So, best to tune to the instrument whose pitch will be least flexible.  

The Historically Informed movement frequently emphasizes tuning.  I wonder if the tunings they choose contribute to the occasional scratchy sounds the string players produce