# Why does 50% volume on video and music players not sound half as loud as 100% volume?

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Usually if a video is too loud, 75% sounds almost the same as 100% and only at around 30% there is a noticeable difference in volume.

In: Technology

In all seriousness maybe you need to have your ears checked? To myself, there’s a significant noticeable difference between 75 & 100% volume. Just as to my ears 50% sounds roughly half of what full volume sounds like. It’s not perfect but I notice the difference with every turn of the knob up or down in volume. If you don’t you should have your sound equipment checked or your ears.

Human hearing is complex. For something to be perceived as twice as loud, it needs to be 10 dB louder, which is 10x power. But to be 4x louder, it’s 20 dB louder which is 100 times as much power.

So it really depends how the player has implemented it’s volume slider. If it does it linearly, i.e if you have it at 50% it just multiplies the audio signal by 0.5, then it’s be way to sensitive at one end and not enough at the other.

So the volume slider should probably be linear in dB.

Human hearing works on a logarithmic scale while usually the player volume bar is on a linear scale. In really simple terms, you have to use multiplication instead of addition. To put it in numerical terms with an example:
– Start with volume at 10% and move to 20%. The value has been multiplied by 2. To increase the perceived volume further by the same amount, you have to multiply again. So the next step is 40%, then 80%.

Working with your numbers, going from 100% to 50% doesn’t halve the perceived volume but it reduces it by some amount. If you want to reduce it again by the same amount, you have to go from 50% to 25%, then 12.5% and so on.

Since you are on a logarithmic scale and addition has been replaced by multiplication, it’s hard to provide a meaningful definition of “half as loud”. This is highly subjective and difficult to put in numbers.

There’s a term that maybe someone can come remind me of but basically, the more of something your sensing, the more you need to perceive a change. This applies to all your senses too. So like if my mouth was empty and you put a single grain of salt on it I’d taist it, but if my younger already has salt on it I wouldn’t notice one more grain.

Logarithmic scaling of dB as others have mentioned, contemporary music is heavily compressed and limited as well, this changes the dynamics. There are tonnes of youtube info on compression and limiting. The whole EDM genre is basically compression and limiting