Cockpit Enviornment

Hi all, I have been using a mix of 2 different wav files for the gyro sounds for my airliners to create a realistic cockpit enviornment sound for example avionics and AC sounds. I flew on a southwest 737-300 and I must say getting a looking a sitting in the cockpit it very quiet at the gate with engines off. There is a very slight noice level of the avionics. Erick Cantu's DC-9 series sounds have a flie called "COCKPITFANS" I think that resembles these sounds quiet well. My questions is do all airliners have this ticking sound in the cockpit? I am planing in useing this COCKPITFAN sounds for all my airliners. Does the 757, 767, 777, 747...and so on (bigger airliners) have this ticking sound in the cockpit or are other airliners beside the 727, 737, DC-9 BAC-1-11 have differenet cockpit sounds while engines shut off at the gate. What is it like for an Airbus? Please share some insite on this.Thanks everyone,Bill