Hi list,
I'm using dbtorms for amplitude control as follows:
signal in volume (0 to 100dB) | | | [dbtorms] | | | [$1 50< | | | [line~] | / [*~] | [dac~]
This is AFAIK the correct way to use it. The problem is, the amplitude scaling doesn't sound right to my ears. 100dB is the loudest and 0dB is silence all right, but 50dB is extremely quiet. I thought that dB in this case are supposed to represent 'loudness', so 50dB should sound half as loud as 100dB? To me 'halfway' seems to be somewhere between 80dB and 85dB. Is it my patch or my ears?
Thanks
Stefan Turner
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ciao
the [dbtorms] works quit correct afaik. actually, +6dB means a doubling of the amplitude. at 48dB (in a scale from 0 to 100dB) your signal has an amplitude of around 1/(2^6)=0.02, wich is quite quiet. on one hand we have a linear scale, where on the upper half happens almost nothing, and in the lower half it is quit difficult to adjust the volume precisely. on the other hand we have the logarithmic scale, where it is difficult too to adjust the volume, because the signal raises quite much in a very small area. i prefer using the 'square' scale, wich is something like a combination of these two:
[inlet~] | | [slider 0 -1 ] | | | [t f f] | | | | [* ] | | [*~] | [outlet~]
i always use this in order to adjust volumes.
cheers roman
----- Original Message ----- From: "Stefan Turner" stefan_turner@yahoo.co.uk To: pd-list@iem.at Sent: Monday, February 28, 2005 5:38 PM Subject: [PD] dbtorms amplitude scaling sounds wrong
Hi Roman, list,
--- Roman Haefeli reduzierer@yahoo.de wrote:
ciao
the [dbtorms] works quit correct afaik.
Yes, I thought it was probably me!
actually, +6dB means a doubling of the amplitude.
Of course it does...don't know why I suddenly thought dB was a linear scale of loudness.
Thanks for the suggestion, I will give this a try. Does this work because power is proportional to amplitude squared? And do you know if it is what mixer faders, for example, (both software and hardware) would generally use? I am interested to know what the 'right' way is.
Thanks for your help.
Stefan Turner
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Thanks for the pointer. Unfortunately my IEMlib is quite old and I don't seem to have [fadto*] (I'm using CCRMA) but [fade~] looks interesting and is I guess fairly similar, so I will definitely give that a go.
Stefan Turner
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