org-ascii-headline-spacing

org-ascii-headline-spacing is a variable defined in `ox-ascii.el'.
Its value is

(1 . 2)

Documentation:
Number of blank lines inserted around headlines.

This variable can be set to a cons cell. In that case, its car
represents the number of blank lines present before headline
contents whereas its cdr reflects the number of blank lines after
contents.

A nil value replicates the number of blank lines found in the
original Org buffer at the same place.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.4 of Emacs.