Page "reviews" Paragraph 67

London explains that the very distinct directional effect in the Phase 4 series is due in large part to their novel methods of microphoning and recording the music on a number of separate tape channels.

These are then mixed by their sound engineers with the active co-operation of the musical staff and combined into the final two channels which are impressed on the record.

In some of the numbers the instrumental parts have even been recorded at different times and then later combined on the master tape to produce special effects.