Render tune title, subtitle and composer in Latex/HTML and not in the image. This way the titles remains a constant size even if the image needs to be scaled. And we have that text appearance under our control. I can't find a way of switching off the tune title in abcm2ps, and have worked around by setting the title format to Y0. Y is not a defined ABC header and is not found in any Dottes tune.

% Format for a graphic with a single tune
continueall false
measurenb false
writefields SRBDZHN 0
titleformat Y0
titlespace 0
topspace 0
infoline false
writehistory false
musiconly true
scale 0.9
botmargin 0pt
leftmargin 0pt
rightmarin 0pt
topmargin 0pt