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The Doppler Effect




The well known Doppler Effect is a major contributor of high rotor speeds for high frequency (the horn) but does not account for the richness for low frequency or when the rotor slows down:


When the source of the sound is ORBITING very slowly inside the cabinet, you hear a very distinct sound. That sound is not the Doppler Effect, it's the phase shift of multiple paths, differential delays and cancellations outside the cab that is reaching your ear.


The very little Doppler EFFECT in low speed of the horn moving cannot be heard. Sound displacement (fast movement) is what creates the Doppler Effect. The sound moves at the same fast speed all the time. That's what makes Doppler work.


The Doppler Effect only happens when the sound source is running fast. When the source of the sound, the horn in the cabinet, goes very slowly it's producing very, very little Doppler Effect.


Differential delays in our ORBITED speaker system is all produced electronically with the cancellations happening outside in the air just like with the traditional rotary cabinet.


We at Amplification discovered this with one of our initial experiments was where we did nothing but change the frequency as with the Doppler Effect. It sounded horrible.


The labels on the half-moon switch explain this very succinctly. The high speed is called tremolo because of the variation in pitch due to the Doppler Effect


At the slow speed on the half-moon switch there's no Doppler Effect that you can hear. It's not discernible.


Back to Technology

Why ORBITED?

Rotary Speakers also ORBIT

It's all about the resonances bouncing inside the box... or is it?

One More Note

How the ORBITED speaker is different from Electronic Simulators

Mic Placement for a Rotary Cabinet

Mic'ing a Rotary Cabinet on Stage

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