iPad Airprint - poor text quality

When I print text from e.g. Word or a PDF, the printed letters all look a bit jagged. The quality is not comparable to a print I do from a computer. This is when I print Truetype fonts. It gets really bad when I print PDFs that contain Postscript fonts (Type 1 or Opentype CSS). Is this normal?

My printer is a Samsung M2825ND. I activated high quality in the printers web server (Syncthru).