Difference between Exponential and Logarithmic as applied to Audio Frequency & Volume

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Difference between Exponential and Logarithmic as applied to Audio Frequency & Volume

I'm trying to understand the differences/similarities between the Exponential curve that represents a controlled change in Frequency and the Logarithmic curve that represents a controlled change in Volume.

My understanding is that the human ear responds to changes in Frequency in an Exponential manner. e.g. In Voltage-Controlled synths using the 1V Oct standard an increase of 1 Volt CV causes a doubling of Frequency. This is easy to plot on a graph and I've seen equations to express it.

For a change in Volume, Amplitude or Attenuation using a potentiometer, it is recommended to use a Pot with a Logarithmic curve. I've seen this curve plotted (**broken link removed** for example) and it has a similar shape to an Exponential Frequency curve - but I can't remember seeing an equation to express this or any discussion of the differences/similarities between these two curve types - Frequency and Amplitude.

Are they different? What are the differences? I hope this question makes sense - I have Googled this a few times now but I've not found an answer that is clear and specific to audio.

Thanks.

 

[FvM]

Re: Difference between Exponential and Logarithmic as applied to Audio Frequency & Vo

Both sound pressure ("power") and frequency perception are linear on a logarithmic scale.