This video demonstrates one of the secrets of Jean Michel Jarre‘s synth sounds – using a phaser on string synth.
If you want the OXYGENE / JARRE sound – and an Eminent 310 organ is to heavy, too big, too expensive for you – a Roland RS-09 “Organ / Strings” for example, can deliver a similar sound.
The sound is not 100% authentic like played with an Eminent, but it is a quite good compromise.
The RS-09 is lightweight, compact and perfect for live performances.
On this video you hear a Roland RS-09, a Roland DEP-5 for delay and an Electro-Harmonix Small Stone Pedal.