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#### LowerFE

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I'm wondering, since a 3dB increase in volume is 2x the sound energy, and 10dB increase is 10x the sound energy. Then why do I see less than twice the excursion when I raise the volume by 3dB on the receiver?

When I turn up my volume by 10dB, I expect to see a 10x increase in cone excursion, but I see more like 2x more excursion, and the sub isn't bottoming out.

Any thoughts?

#### BeeMan458

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Quote:
Originally Posted by LowerFE  /t/1470022/how-come-3db-higher-volume-does-not-translate-to-2x-more-excursion#post_23247179

Any thoughts?

Nope.

Why, it's a mechanical process based on many factors and all I care about, do I approve of what I'm hearing.

3dB is a doubling of power and 10dB is a doubling of perceived sound.

A three dB increase can be caused by simply doubling the amount of energy going to the coils, from say, 1w to 2w or how ever much energy is required to go from 75dB to 78dB. If a doubling of excursion was the case, by the time a subwoofer driver got up to 108dB, you'd have a throw as long as the room.

Maybe you can share a bit more insight regarding your concerns as to how you're thinking things should work so better minds (more educated) can respond with more insightful thoughts.

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#### Bill Fitzmaurice

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Quote:
Originally Posted by LowerFE  /t/1470022/how-come-3db-higher-volume-does-not-translate-to-2x-more-excursion#post_23247179

why do I see less than twice the excursion when I raise the volume by 3dB on the receiver?
Excursion is proportional to voltage swing, not power. A doubling of voltage swing will result in a doubling of excursion, which will give a 6dB increase in output and power draw. A 3dB increase in power increases voltage swing by a factor of 1.4, so a 3dB power and SPL increase results in an excursion increase of a factor of 1.4.

#### thehun

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Quote:
Originally Posted by LowerFE  /t/1470022/how-come-3db-higher-volume-does-not-translate-to-2x-more-excursion#post_23247179

I'm wondering, since a 3dB increase in volume is 2x the sound energy

Any thoughts?

Simple, you confusing acoustical output versus electrical power output. 3db acoustic increase requiring to double the amp output, but that doesn't produce 2x the sound pressure [acoustic output]

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