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Reverse an exponential scale


Mar 12 2010 | 9:21 am

I know that I can replicate the exponential scaling of [gain~] with [scale 0 157 0. 7.942307 1.071519]. My question is, what exponential value would I use to reverse that process? In other words [scale 0. 7.942307 0 157 ???]. Thanks.

Mar 12 2010 | 10:22 am

dbtoa / atodb [?]

Mar 12 2010 | 7:54 pm

I thought about that, but it’s not dB and amplitude. It’s that strange relationship between amplitude and 158 that is present in the [gain~] object.

Mar 12 2010 | 8:42 pm

This should explain the [gain~] equation and you can see how to do the reverse to get you back to where you started.

lh


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Mar 12 2010 | 9:19 pm

Thank you Luke! That’s exactly what I was looking for.

Mar 13 2010 | 1:29 am

i usually scale the range down to 0-1, reverse that, and scale it up again.

Mar 13 2010 | 8:03 am

With the default parameter, there’s 6 dB for 10 increments. So it’s easy to find the value in db. It’s more or less the same patch as Luke, but you might get easier the 6db per 10 ints by not including the dbtoa conversion in the expr.


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