gregorio
Headphoneus Supremus
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Why?Pitch and frequency need to be kept clearly separated here.
G
Why?Pitch and frequency need to be kept clearly separated here.
Ah right, I see. I was thinking in terms of musical note pitch rather its meaning of a subjective perception.The pitch(subjective perception) can seem to progressively go up as the car gets close.
It is a combination of physical and perceptual phenomena. Physical phenomena can of course be recorded. Stereo sound is also perceptual, an illusion even, but we still can make stereo recordings. The physical and perceptual sides are linked in more of less complex manner. To put it more precisely: We can record Doppler effect, but not Doppler illusion. The recording doesn't have the rising pitch in it, but that's what we perceive as an illusion according to this study.If it’s perceptual, why can the Doppler effect be recorded?
Yes. That's why this is tricky. There is a real physical frequency change, but it isn't exactly what we perceive:Ok. I knew there had to be a physical aspect. I have demonstration records of steam locomotives that are vivid examples.
It doesn’t slowly drop, it stays constant (assuming a constant speed) and then drops quite quickly as it passes and then stays constant again. The pitch change actually occurs over a period typically of 0.5 - 1 second, although obviously depends on the speed of the vehicle.Is higher than the source frequency in the beginning and drops slowly until the sound source bypasses (minimal distance) and the frequency drops fast below the source frequency and then slower as the source moves away.
It is sometimes but it’s quite rare in music production. It’s very common in film sound though, obviously there are often vehicle passbys, including aircraft. If fact there are entire sound libraries of passby but sometimes we need to create our own for various things, from artillery and other weapons or projectiles to flying insects. There are a number of plugins to help with the process and all sound designers/mixers have at least one in their collection.Who knows, maybe this can even be used in music production to create certain sonic illusions?
It varies, not only from person to person but for the same person, on one occasion they maybe subject to the illusion and on another occasion they may not be.I don’t seem to be subject to the illusion. I don’t hear a change in pitch on approach, just volume.