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Re: Decay rate and time



>Is there an estimate of decay time based on position of feedback dial?
>For instance, how long will it take for a layer to decay completely if
>the feedback dial is positioned at 3 O'clock?  12 O'clock? 9 O'Clock?
>
>Regards,
>Jeff

Hey Jeff!
You cited a long text to ask this question ;-)
But it is related and interesting:

As the FB is a rate, there is not "complete decay". Its a "geometric 
sequence" if I remember the math correctly.
If the FB control is linear, 12 O'clock brings a rate of 1/2: Each 
repetition is half as loud as the previous one. But its never totally 
gone.
In the analogy with history: Most facts can still be found in some 
documents, but at some point, they may be considered "unimportant" or 
"outdated".

To have a base to measure decay time, the engineers defined the 
reverb time as the time it takes until the sound is 60dB weaker than 
the original. But this is not a truth, just a definition, just like 
defining how loud "silence" and "too loud" is.
Since a factor 2 means 6dB, that would correspond to 10 repetitions, right?

So roughly, we could say that with FB at 12 O'clock we repeat 10 times.

The idea to have the FB rate depending on the loop time to achieve an 
absolute fading time has been arround for a while (also on this list?)
Technically it would not be complicated. We may have it in the 
future, but I suspect it will not be perfectly usefull either...
-- 


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