Complex sentence: Like 78s, early soundtrack discs were pressed in an abrasive shellac compound and played with a single-use steel needle held in a massive electromagnetic pickup with a tracking force of five ounces.
Split into simpler sentences: Like 78s, early soundtrack discs were pressed in an abrasive shellac compound. They were played with a single-use steel needle held in a massive electromagnetic pickup with a tracking force of five ounces.