I was kicked out of Comhaltas for 3 months for playing an A7 on a run down from Em to D.

I was about 13 at the time, and was told in no uncertain terms the we'll have 'None of that oul' Bothy Band stuff in here'

By some folks' yardsticks, the only traditional Irish instrument there is, therefore, are a set of bones.

Of course they would have to be Irish bones, I would imagine.

There's 'purists' everywhere.
Don't mind them...

But I would have to ask cromdubh to look a bit closer at the Acoustic Bass.
I played one in a 'Ballad Folk' band at the end of the 70's, and accompanied trad on it, as well.
It is played differently from an Electric one, and it is always the case that the crossover from Electric to acoustic is much harder that if you started out playing the acoustic version of first.

Try the backwards step, cromdubh.
I'm sure, eventually, you'll appreciate the difference.

And not a double (contra) bass!
Not if you go to gigs in a Ford Fiesta......

Oh, God be with the good old days, what?

B.