4.1 to stereo

[mrkazador]

24 bit 96khz 4.1 FLAC
I tried using Eac3to with the -down2 command but it doesn't work with a 4.1 source, 5.1 is fine. It outputs 5 channels which is exactly as the source. Any way to get this to work or with something else keeping it 24bit 96khz?

[bertox]

Try to change de order of channels. I'm using eac3togui downmixing a 5.0 source without problems.

Place in this order: 0,1,4,2,3

You want to try using SoundForge too, for viewing the orders of channels, cause' very often, in 4.1 or 5.0 sources they are truly bad accommodate!! Compare this with a 5.1 file in SoundForge. You see in the 4.1 source the LFE channel stays in number 5 channel; when in 5.1 source it stays always in the meddle of fronts and rears channels. The 5.1 mix show you the mix matrix as it should be. You follow it, then you get it...:D

But, i warn you, the downmix in eac3to is not a "dry" mix, it is a Prologic II mix; who works only to "re-create" the multichannel image in receivers who accept this.

I'm now into requesting the "dry" downmix option to the developer of the eac3to, he's answer is: not very soon i implement this...minus for a single person...(me).
You could sum in the push of requesting if you want...

You can do the downmix in SoundForge too...

Sorry my bad english. Victor, from Argentina.

[mrkazador]

I get an error, This audio conversion is not supported. Without the command 0,1,4,2,3 it outputs fine...I'll see about SoundForge.

[tebasuna51]

First of all, what is 4.1?
FL,FR,SL,SR,LFE
or
FL,FR,C,S,LFE?

The mix is different, if is FL,FR,C,S,LFE you can try:
fl' = C1xFL + C2xC + C2xS + C2xLFE
fr' = C1xFR + C2xC + C2xS + C2xLFE

Or without LFE like Dolby recommend:
fl' = C1xFL + C2xC + C2xS
fr' = C1xFR + C2xC + C2xS

Or maybe do you want a Dolby ProLogic mix:
fl' = C1xFL + C2xC + C2xS + C2xLFE
fr' = C1xFR + C2xC - C2xS + C2xLFE

Or DPL without LFE like Dolby recommend:
fl' = C1xFL + C2xC + C2xS
fr' = C1xFR + C2xC - C2xS

Or do you want ignore the surround channel:
fl' = C1xFL + C2xC
fr' = C1xFR + C2xC

But if the 4.1 is FL,FR,SL,SR,LFE you can use:
fl' = C1xFL + C1xSL + C2xLFE
fr' = C1xFR + C1xSR + C2xLFE

And so on ...

- Where C1 is the cofficient to apply if the source channel is present in only a final channel.

- C2 is the cofficient to apply if the source channel is present in two final channel and is:
C2 = C1 / SQR(2)
Now the sum of audio power from the two channel is equivalent to the original audio power.

- To avoid overflow in any equation the sum of the absolute values of the coefficients must be 1
For instance in:
fr' = C1xFR + C2xC - C2xS + C2xLFE
1 = C1 + C1/SQR(2) + C1/SQR(2) + C1/SQR(2)
C1 = 1 / (1 + 3/SQR(2)) = 0.3204
C2 = 0.2265
fr' = 0.3204xFR + 0.2265xC - 0.2265xS + 0.2265xLFE

Well, we can see there are many options and only the more habitual can be implemented in soft like eac3to.
If you want your particular mix you can use the matrix mixer in ffdshow, foobar2000 with the adecuate channel mixer dsp, or use an AviSynth method.

[tebasuna51]

@bertox
You can listen the Dolby ProLogic II mix in stereo only equipment with very few differences with the "dry" downmix

[bertox]

Dolby ProLogic II sounds very bad...he had phase changes and rare matrixing. ProLogic II works only in equipment who accept this and this "rare form" is to "re-create" a multichannel system from a stereo source.

For me, dry mix are:
FL' = FL + C + LFE + SL
FR' = FR + C + LFE + SR

With 8db to 9db attenuate matrixing for clipping avoid. Simple.

[bertox]

I get an error, This audio conversion is not supported. Without the command 0,1,4,2,3 it outputs fine...
The "0,1,4,2,3" what i post are not in command line form....

You want to use eac3togui to see how configure channels mapping.

This work for me. You are doing some things bad...

[tebasuna51]

Dolby ProLogic II sounds very bad...he had phase changes and rare matrixing. ProLogic II works only in equipment who accept this and this "rare form" is to "re-create" a multichannel system from a stereo source.

Is your opinion. BTW SL and SR are already phase shifted if came from 5.1 Dolby Digital compliant and are only inverted in right channel to do the DPL mix.

For me, dry mix are:
FL' = FL + C + LFE + SL
FR' = FR + C + LFE + SR

With 8db to 9db attenuate matrixing for clipping avoid. Simple.

Of course you are free to do your 'bertox' mix, but C and LFE have more volume than FL- FR and add LFE to others channels can produce undesired artifacts, ... is other custom mix that I never can recommend include in eac3to.

[bertox]

Is your opinion. BTW SL and SR are already phase shifted if came from 5.1 Dolby Digital compliant and are only inverted in right channel to do the DPL mix.

This is NOT "my opinion". This is the REAL FACT.
If you don't have a system who re-create the ProLogic II sources you only hear a trash mixing. I don't like the idea to listening my music with phase shifting channels!!!!!
I love how my music was recorded, without phase shifting in any of his channels!!!!!!!!!


... C and LFE have more volume than FL- FR and add LFE to others channels can produce undesired artifacts

C and LFE have more volume??? Where?? Do you open a 5.1 wav in SoundForge ever and verify what you say??? I don't think so...

Add LFE to others channels can produce undesired artifacts????
EEEHHHH????!!!!! I have music mixes who have a dedicated recorded mixed independent LFE channel.-
Why i don't have to add this beautiful recorded LFE channel to my stereo downmix???? Undesired artifacts??? jajajaja. I don't think so...
I SAY:"With 8db to 9db attenuate matrixing for clipping avoid"
I hope you understand this...

...is other custom mix that I never can recommend include in eac3to.
You do what you do....
I do what I do. One matrixing request in eac3to for the people who don't have receivers....

[tebasuna51]

About LFE mix from 214_Mixing with Dolby Pro Logic II Technology.pdf :
"There are other concerns when adding an LFE signal to the mix. If the LFE is simply redistributed within the other channels of the mix, they will usually be subject to some low-frequency bandpass filtering. This filtering causes phase shifts of the LFE signal. When they are acoustically added within a room, these phase shifts are fairly subtle and often go unnoticed. However, when they are electronically added together with the five main channels in the encoder, they may produce less than desirable results at certain frequencies. For this reason, it is recommended that the LFE signal not be used in a Dolby Pro Logic II downmix unless it contains unique information that is not repeated in any of the five main channels."

This is the DPL II downmix in BeHappy:
fl' = 0.3254xFL + 0.2301xC + 0.2818xSL + 0.1627xSR
fr' = 0.3254xFR + 0.2301xC - 0.1627xSL - 0.2818xSR

And this the Simple Stereo mix in BeHappy also:
fl' = 0.2929xFL + 0.2071xC + 0.2071xLFE + 0.2929xSL
fr' = 0.2929xFR + 0.2071xC + 0.2071xLFE + 0.2929xSR

(the coefficients of repeated channels must be less to maintain the relative volume equivalent, how was recorded)

With ffdshow is easy make test with these and others matrixes.
Everybody is free to select your choice, I don't believe in 'REAL FACTS'.

BTW, I always select maintain the original 5.1.

[bertox]

ok. and you still talking about ProLogic....

Repeat: DPL Don't work for me and for the long masses who don't have receivers and 5.1 speakers system for re-construct from DPL II sources. dot.

If you read what i say perhaps you notice that i know what is a normalized matrix.

I note that you are not understanding which is my point. I never refuse de functions of the ProLogic mix and a normalized matrix (what i obviously using).

I hope you'll understand my point and not going in battle with me unnecessarily.

I don't believe in 'REAL FACTS' too; i'm Marxist, not a fucking Hegelian. Please, this is not funny.....you don't understand me.

Prologic sounds bad in a stereo only system. This is a fact...please...http://en.wikipedia.org/wiki/Dolby_Pro_Logic
Is only for multispeaker systems.

Well...i assumed that it was talking about downmixing to stereo for stereo listening in this thread...
And i go home now cause' mrkazador is not talking anymore.

bye bye and good luck.

[nautilus7]

DPL Don't work for me and for the long masses who don't have receivers and 5.1 speakers system for re-create DPL II sources.
You keep telling about this. Can you explain why a 5.1 system is needed for listening a 2.0 audio track? :confused: Because such is the down mixed one.


PS: I would recommend being polite and respect tebasuna51 and others who are trying to help you.

[bertox]

Because the DolbyPrologic II is a Mixing Matrix create to re-construct a multichannel system from a stereo only source.

Read this: http://en.wikipedia.org/wiki/Dolby_Pro_Logic
and: http://forum.doom9.org/showthread.php?p=1005866#post1005866

DolbyPrologic II is not for Stereo listening.

P.D: i respect everybody who don't fight me unnecessarily. The tebasuna51 says really hurt me (I don't believe in 'REAL FACTS') i don't be a fuckin' dogmatic or religious man. I'm sorry if he don't ndrstnd me...but hes may not had to have hurt me senseless.

[tebasuna51]

@bertox
Sorry if I hurt your senseless.
I'm also marxist but I don't think we need make the 'class struggle' with the audio surround.

I put the two ways not only for you, but for everybody like is offered in BeHappy.

Maybe is time to smoke the 'peace pipe'... or something like in your avatar.

[patul]

@bertox: tebasuna51 talks about the standard set by Dolby, and if it does not fit your "real facts", then your taste must be involved in your judgment. We're talking about "proper way" to downmix according to the recommendation, not about personal taste. You can't mix both of them..

And by the way, English is not tebasuna51's native language, so if permitted, I would suggest you to be little bit more open minded.

[bertox]

@tebasuna51:

jajaja. ok ok.

But i'm not speak about Marx in vain, just only comparing to Hegel who talk about the "absolute trues of god" despite of his advanced philosophy studies (dialectics, etc).

BSODS...., digo....besos (spanish talking) jajaja. Victor, from Argentina.

[bertox]

@patul:

i don't talking about personal tastes ever. i'm just saying that DolbyPrologic II is not for Stereo listening.

And i'm very very open minded person; now, this is nothing to do with the fact that a different language is not brain limiting thing of man. I spanish too (latin) from Argentine ("the dark side of the earth"..., "the world's ass"..). And my english is very bad too, but GoogleTranslate helps me, and my experience...and my mother (who speak english better than me) too.:D