Complex sentence: The firm is now run by John Mander, Noel Mander's son and pipe organs have been built and installed in Australia, Japan, Middle East, New Zealand, Scandinavia and the United States.
Split into simpler sentences: The firm is now run by John Mander, Noel Mander's son. Their organs are installed in Australia, Japan, Middle East, New Zealand, Scandinavia and the United States.