Clip au dessus de 0dB
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+1
cool, mais je n'ai pas bien compris non plus, à propos des 32bits à virgule flottante 
L'asio en paramétré en 24bits (en regard de la carte son!!)
Cubase gère le 32bits à virgule flottante, ok, et maintenant,
on fait quoi et à quoi ça sert ?
Et, peut-on re-expliquer pourquoi le master ne clippe pas en 32bits à virgule flottante
Moi, j'ai remarqué que quand j'ai fait un mix de toutes les pistes, j'utilise le compresseur dynamique sur le mix avec une correction grave et aigüs, si je modifie le fader du compresseur, je peux faire monter ou baisser le volume de ce que j'entends, sans modifier la réaction du volume sur le curseur de sortie
Ensuite, je vérifie l'export (en wave 44.100KHz 16bits) avec Wavelab6, et je le compare avec les autres titres du CD, je baisse le volume à -0.3db et, c'est ce fichier que je mets sur le CD.
Donc, je n'ai pas trouvé l'utilité du 32bits à virgule flottante
ai-je tort ?
- 1
- 2
Romjé
1999
AFicionado·a
Membre depuis 21 ans
snafu
3514
Squatteur·euse d’AF
Membre depuis 21 ans
Romjé
1999
AFicionado·a
Membre depuis 21 ans
Salut !
Je ne crois pas avoir induit qui que ce soit en erreur. On dit exactement la même chose, en fait
J'ai trouvé qqch de très intéressant qui mélange ce qu'on dit :
*********************************************************
What is 32-bit mode? What is a floating-point number?
Warning, this complicated stuff. I will try and answer and try and do justice
to those who understand the technical background, and say what it means to
everyone.
To start with I have to clear up a misunderstanding. Cubase's internal audio
paths are all native-floating-point paths. That means that we use the
floating-point type supported by our compiler and your platform combination.
But what are floating-point numbers?
Floating point number are just one of many possible way to represent a value
with a small chunk of memory in your computer, or a section of your disk drive.
Simple but there are two types: Integer numbers and floating-point types.
Floating-point numbers differ from Integer numbers in that they can scale
themselves internally to be able to represent very big and very small numbers
without losing significant detail. The other kind, integers have a fixed finite
range: a 16-bit integer can represent 65535 different discrete values. A 24-bit
number can represent 16777216 different discrete values. And a 32-bit INTEGER
number can represent 4294967296 different discrete values. Sounds great but all
these integer number have the same disadvantage that as the number they try and
represent get smaller, the number of bits that the number uses to represent
itself, falls. Therefore the SIGNIFICANT ERROR in representing a small analogue
sample increases as the number gets smaller as the number can only be 1, 2, 3
.... n. There is no 1 and bit, just a bit less than 2 etc.
Floating-point numbers offer exactly that: A number with a decimal point where
the point can move, A number can be represented as fractional parts. That is
the number can be 1.00001, or 2.55555, or 95522041.1456, it doesn't matter.
Internally inside a 32 bit floating point number 24 bits are just to represent
the number required between 0.0000000 and 0.999999, and the remaining 8 bits
are used to scale the number to the right range. (a gross simplification!) If
you ever did maths where numbers were represented as...
2.3 * 10^3
4.4589 * 10^-4 (sorry that does not work well in text)
... then you will see an analogy here.
So a floating-point number has the capacity to represent HUGE numbers and
maintain accuracy with very small numbers.
Cubase VST uses a nominal operating level inside this floating point range,
such that there is a more than sufficient accuracy to represent the finest
detail BUT still have a massive head room. (Someone once calculated 1500 dB
headroom - but I think that gives false impression)
The massive headroom is what enables you to pile on tracks, and lower the
master fader when the summed signal cannot be represented anymore by the
INTEGER bits of your sound card. Lowering the master fader is changing the
scaling value as the floating point values are converted to integer bits for
the audio card. The advantage is that you can pile on the tracks and if the
FINAL output clips you can just turn down the master fader, and not be forced
to reduce each fader in tern until the clipping at the output disappears.
The accuracy at lower levels is why you don't need to really worry about
optimising auxiliary-send levels etc. With analogue equipment it would
potentially lead to noise build up, with VST is not really critical.
So to sum up a 32 bit floating point representation for audio can define very
small signals, and is practically OVERLOAD proof.
Cubase actually uses many more bits when working on the calculation within the
main processor: where 80 or 96 bits (or 151 bits on a PowerPC!) of information
represent the result of adding or multiplying a series of floating point
numbers.
But what's new in Cubase VST/32 is that Audio files can exist in 32-bit point
format! A 32-bit floating-point file has all the characteristics of a 32 number
in memory. It maintains accuracy a when representing very small numbers, but
has a huge headroom over the nominal operating level.
The question everyone asks is, 'what has that to do with recording audio when
my sound card is only 16/24 bits?' It is sure that recording 16 or 24 bit data
into a 32-bit file gains nothing, at first sight, it can't MAKE more accuracy
for example.
But the advantages lie elsewhere.
Consider the action of exporting your song. In previous Cubase versions and
anyone else's 16/24 bit application for that matter, as soon as you leave the
VST floating point world and make a decision to set the conversion to integer
numbers (the master fader) and pack the result into a file. Get it wrong and
the file is clipped or not using the full range of values, increasing
distortion. With a floating point export file you are exporting without having
to make a decision about the level of the conversion to integer numbers. That
means either you can further process the file in you favourite mastering
package, or make the final level matching of multiple tracks etc, without first
having squeezed your music through a thoroughly unnecessary quality reduction
stage.
Consider the action making a MIXDOWN, because it's obviously related to
exporting audio. The main reason from mixing down is that the computer cannot
cope with the tracks and synths you want to run simultaneously. While
performing this mixdown you have to choose a conversion level so the mixed file
doesn't clip. Too low and you introduce quantising artefacts. But mixing down
to a floating-point file means it's practically irrelevant. Just Do it. You
loose FAR less than when mixing to integer file and you can't clip them. As a
side line subjectively speaking apart from the removal of the clipping issue,
the main thing is that they just sound damn good. - Wonderful dynamics. I'll
stop there before someone accuses me of trying to sell this to you.
Now on to a new recording mode that comes with the VST/32: TrueTape. This is a
part of the concept, as a process is sits precisely at the point where the
24/16 bit signal is converted into the internal VST BIG floating point number.
It is generating MORE detail, than the original signal contained. That sounds
impossible and it is of course, TrueTape models the transfer process of a
analogue tape recorder, and as it is a process, it generates data direct in the
floating point world that is more detailed than the original signal. But of
course yes it has a sound! - Because that what is supposed to do. So if you are
interested in the TrueTape process, it's a very good reason to record as 32 bit
float files.
David Nicholson
Cubase Project Manager
Steinberg Media Technologies 2000
**************************************************************
Ca correspond à ce que je disais, non ?
@+
Romjé.
Je ne crois pas avoir induit qui que ce soit en erreur. On dit exactement la même chose, en fait
J'ai trouvé qqch de très intéressant qui mélange ce qu'on dit :
*********************************************************
What is 32-bit mode? What is a floating-point number?
Warning, this complicated stuff. I will try and answer and try and do justice
to those who understand the technical background, and say what it means to
everyone.
To start with I have to clear up a misunderstanding. Cubase's internal audio
paths are all native-floating-point paths. That means that we use the
floating-point type supported by our compiler and your platform combination.
But what are floating-point numbers?
Floating point number are just one of many possible way to represent a value
with a small chunk of memory in your computer, or a section of your disk drive.
Simple but there are two types: Integer numbers and floating-point types.
Floating-point numbers differ from Integer numbers in that they can scale
themselves internally to be able to represent very big and very small numbers
without losing significant detail. The other kind, integers have a fixed finite
range: a 16-bit integer can represent 65535 different discrete values. A 24-bit
number can represent 16777216 different discrete values. And a 32-bit INTEGER
number can represent 4294967296 different discrete values. Sounds great but all
these integer number have the same disadvantage that as the number they try and
represent get smaller, the number of bits that the number uses to represent
itself, falls. Therefore the SIGNIFICANT ERROR in representing a small analogue
sample increases as the number gets smaller as the number can only be 1, 2, 3
.... n. There is no 1 and bit, just a bit less than 2 etc.
Floating-point numbers offer exactly that: A number with a decimal point where
the point can move, A number can be represented as fractional parts. That is
the number can be 1.00001, or 2.55555, or 95522041.1456, it doesn't matter.
Internally inside a 32 bit floating point number 24 bits are just to represent
the number required between 0.0000000 and 0.999999, and the remaining 8 bits
are used to scale the number to the right range. (a gross simplification!) If
you ever did maths where numbers were represented as...
2.3 * 10^3
4.4589 * 10^-4 (sorry that does not work well in text)
... then you will see an analogy here.
So a floating-point number has the capacity to represent HUGE numbers and
maintain accuracy with very small numbers.
Cubase VST uses a nominal operating level inside this floating point range,
such that there is a more than sufficient accuracy to represent the finest
detail BUT still have a massive head room. (Someone once calculated 1500 dB
headroom - but I think that gives false impression)
The massive headroom is what enables you to pile on tracks, and lower the
master fader when the summed signal cannot be represented anymore by the
INTEGER bits of your sound card. Lowering the master fader is changing the
scaling value as the floating point values are converted to integer bits for
the audio card. The advantage is that you can pile on the tracks and if the
FINAL output clips you can just turn down the master fader, and not be forced
to reduce each fader in tern until the clipping at the output disappears.
The accuracy at lower levels is why you don't need to really worry about
optimising auxiliary-send levels etc. With analogue equipment it would
potentially lead to noise build up, with VST is not really critical.
So to sum up a 32 bit floating point representation for audio can define very
small signals, and is practically OVERLOAD proof.
Cubase actually uses many more bits when working on the calculation within the
main processor: where 80 or 96 bits (or 151 bits on a PowerPC!) of information
represent the result of adding or multiplying a series of floating point
numbers.
But what's new in Cubase VST/32 is that Audio files can exist in 32-bit point
format! A 32-bit floating-point file has all the characteristics of a 32 number
in memory. It maintains accuracy a when representing very small numbers, but
has a huge headroom over the nominal operating level.
The question everyone asks is, 'what has that to do with recording audio when
my sound card is only 16/24 bits?' It is sure that recording 16 or 24 bit data
into a 32-bit file gains nothing, at first sight, it can't MAKE more accuracy
for example.
But the advantages lie elsewhere.
Consider the action of exporting your song. In previous Cubase versions and
anyone else's 16/24 bit application for that matter, as soon as you leave the
VST floating point world and make a decision to set the conversion to integer
numbers (the master fader) and pack the result into a file. Get it wrong and
the file is clipped or not using the full range of values, increasing
distortion. With a floating point export file you are exporting without having
to make a decision about the level of the conversion to integer numbers. That
means either you can further process the file in you favourite mastering
package, or make the final level matching of multiple tracks etc, without first
having squeezed your music through a thoroughly unnecessary quality reduction
stage.
Consider the action making a MIXDOWN, because it's obviously related to
exporting audio. The main reason from mixing down is that the computer cannot
cope with the tracks and synths you want to run simultaneously. While
performing this mixdown you have to choose a conversion level so the mixed file
doesn't clip. Too low and you introduce quantising artefacts. But mixing down
to a floating-point file means it's practically irrelevant. Just Do it. You
loose FAR less than when mixing to integer file and you can't clip them. As a
side line subjectively speaking apart from the removal of the clipping issue,
the main thing is that they just sound damn good. - Wonderful dynamics. I'll
stop there before someone accuses me of trying to sell this to you.
Now on to a new recording mode that comes with the VST/32: TrueTape. This is a
part of the concept, as a process is sits precisely at the point where the
24/16 bit signal is converted into the internal VST BIG floating point number.
It is generating MORE detail, than the original signal contained. That sounds
impossible and it is of course, TrueTape models the transfer process of a
analogue tape recorder, and as it is a process, it generates data direct in the
floating point world that is more detailed than the original signal. But of
course yes it has a sound! - Because that what is supposed to do. So if you are
interested in the TrueTape process, it's a very good reason to record as 32 bit
float files.
David Nicholson
Cubase Project Manager
Steinberg Media Technologies 2000
**************************************************************
Ca correspond à ce que je disais, non ?
@+
Romjé.
snafu
3514
Squatteur·euse d’AF
Membre depuis 21 ans
Romjé
1999
AFicionado·a
Membre depuis 21 ans
miles1981
8370
Je poste, donc je suis
Membre depuis 21 ans
bessinnox
5544
Je poste, donc je suis
Membre depuis 23 ans
Au final plus on m'explique et moins je comprends 
S.d.m
4787
Squatteur·euse d’AF
Membre depuis 21 ans
Citation : Au final plus on m'explique et moins je comprends
+1
bessinnox
5544
Je poste, donc je suis
Membre depuis 23 ans
En tout cas je pense avoir compris que le niveau visuel du vu metre n'est pas forcement celui qui est audible, en clair on peut avoir de la patate sans jamais le dépasser et ne rien sortir et être au taquet
j'ai bon ???
j'ai bon ???
Romjé
1999
AFicionado·a
Membre depuis 21 ans
didebmo
737
Posteur·euse AFfolé·e
Membre depuis 20 ans
Question pour faire un remastering perso ou amateur (et donc pour éviter les clics...) :
si je comprends bien, l'idéal avec cubase c'est qu'une fois que le produit est terminé, on ajoute aucun effet au master, on frôle les 0db
et on l'exporte. Ensuite on réimporte ce nouveau WAV dans un PRG de mastering ou si on en n'a pas, on le réimporte dans cubase pour en utiliser les (compression, reverb ...)
si je comprends bien, l'idéal avec cubase c'est qu'une fois que le produit est terminé, on ajoute aucun effet au master, on frôle les 0db
et on l'exporte. Ensuite on réimporte ce nouveau WAV dans un PRG de mastering ou si on en n'a pas, on le réimporte dans cubase pour en utiliser les (compression, reverb ...)Dide
miles1981
8370
Je poste, donc je suis
Membre depuis 21 ans
robi
932
Posteur·euse AFfolé·e
Membre depuis 22 ans
miles1981
8370
Je poste, donc je suis
Membre depuis 21 ans
robi
932
Posteur·euse AFfolé·e
Membre depuis 22 ans
bessinnox
5544
Je poste, donc je suis
Membre depuis 23 ans
Supra mega déterrage
la conversation n'était pas terminée
la conversation n'était pas terminée
robi
932
Posteur·euse AFfolé·e
Membre depuis 22 ans
afone1977
3630
Squatteur·euse d’AF
Membre depuis 20 ans
dprojekt
171
Posteur·euse AFfiné·e
Membre depuis 20 ans
purpletrain
695
Posteur·euse AFfolé·e
Membre depuis 19 ans
cool, mais je n'ai pas bien compris non plus, à propos des 32bits à virgule flottante L'asio en paramétré en 24bits (en regard de la carte son!!)
Cubase gère le 32bits à virgule flottante, ok, et maintenant,
on fait quoi et à quoi ça sert ?
Et, peut-on re-expliquer pourquoi le master ne clippe pas en 32bits à virgule flottante
Moi, j'ai remarqué que quand j'ai fait un mix de toutes les pistes, j'utilise le compresseur dynamique sur le mix avec une correction grave et aigüs, si je modifie le fader du compresseur, je peux faire monter ou baisser le volume de ce que j'entends, sans modifier la réaction du volume sur le curseur de sortie
Ensuite, je vérifie l'export (en wave 44.100KHz 16bits) avec Wavelab6, et je le compare avec les autres titres du CD, je baisse le volume à -0.3db et, c'est ce fichier que je mets sur le CD.
Donc, je n'ai pas trouvé l'utilité du 32bits à virgule flottante
ai-je tort ?
La musique me régénère, alors, jouons!
gderenne
1016
AFicionado·a
Membre depuis 22 ans
lohworm
3727
Squatteur·euse d’AF
Membre depuis 20 ans
purpletrain
695
Posteur·euse AFfolé·e
Membre depuis 19 ans
Merci à vous deux 
La musique me régénère, alors, jouons!
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