Re: [Audacity-nyquist] [Audacity-users] newbie question - db-to-linear

[David R. S. <dav...@sh...>]

Thanks Micael,

I recall having read some years ago that that equation is "only" an 
approximation - is this true and, if so, what's the "exact" equation and 
why isn't it defunned that way in Nyquist?

Thanks - David

-- 
David R. Sky
http://www.shellworld.net/~davidsky/


On Wed, 19 Nov 2008, Mikael wrote:

> -6 dB should not be exactly 0.5, but:
>
> -6 dB -> 10^(-6/20) = 0.50118723...
>
> Regards,
> Mikael
>
> On Wed, Nov 19, 2008 at 8:28 PM, David R. Sky <dav...@sh...> wrote:
>> Thanks for posting the results Gale. I don't know why (db-to-linear -6)
>> isn't _exactly_ 0.5, so I'm cross-posting to the Audacity Nyquist list.
>> (The code in question was entered into the Audacity effects | Nyquist
>> prompt.)
>>
>> David
>>
>> On Wed, 19 Nov 2008, ga...@au... wrote:
>>
>>> On Tue, 18 Nov 2008 11:35:22 -0800 (PST)
>>> "David R. Sky" <dav...@sh...> wrote:
>>
>>>> (format nil "0db = ~a; -6db = ~a"
>>>> (db-to-linear 0) (db-to-linear -6))
>>>>
>>>> You might get an error message displayed, along with values displayed
>>>> which Nyquist understands 0db and -6db to be in linear terms.
>>>
>>> It reads 0 dB as "1" and - 6 dB as "0.501187".
>>>
>>>
>>> Gale
>>>
>>>
>>>
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