GUIDE: Converting stereo to 5.1 surround for FREE

[ursamtl]

Originally Posted by Elektra999

Hello Steve.

I hope anxious, your new guides and programs je je

Not anything that new, just some tips I intend to write for getting the most professional sound possible from freeware tools. There are some things already in the guides, such as using 32 bit files, removing DC offset, using a limiter to avoid clipping, etc. As I read and study the whole field of sound production, I pick up things, so I hope to write some new stuff and update the guides.

[DSP8000]

Hi Steve,

glad to see that you're improving/updating your guide.
Just one suggestion, can you please in your updated version of the guide include vlevel for foobar2000. I find it very useful.
Also, of course Aften, free ac3 encoder that produces excellent output.
Keep up the good work.

Regards,
DSP8000

[ursamtl]

Thanks for the suggestion. I'll check it out. As far as I can tell from a quick Google, it's a compression plugin.

Given the whole loudness war, I usually stay away from compression except for limiting to prevent clipping. Compression can work wonders for a vocal or an individual instrument, but on a whole mix it can crush the life out of the music!

But, there are exceptions. Can you adjust the two channel individually or only as a pair? An individual per channel adjustment would be great for boosting the low LFE as I suggest with the Plogue Bidule layout and Classic Limiter, or for ensuring dialog clarity in a movie soundtrack by compressing the C. Unfortunately, the freeware method in this guide groups the C and LFE channels together so either a plugin with individual channel adjustments or doing separate passes for each would be necessary.

In any case, I'll check it out. Thanks.

Regards,
Steve.

[NorthPole]

@ursamtl

Have you looked at the mp3 surround upmix here http://www.all4mp3.com/info/mp3sx.html

I was wondering what you thought?

There is a command line utility located here http://www.all4mp3.com/tools/sw_fhg_demo.html

Thanks

[ursamtl]

Thanks for the tip. I'll check it out. As a rule, I'm not a big fan of MP3s other than as a convenient compression format for my portable player. For surround work, I always try to stick with lossless source files. I can hear the difference in clarity between MP3s and lossless even at higher bit rates. It's more a matter of dynamics in the highs than anything else. Cymbals, etc., just don't breathe as well. They sound constrained and squashed.

I also know in my tests when developing V.I that mp3s often do not convert well because the psychoacoustic tricks they use for compression get unmasked when one attempts to generate surrounds for example. I remember a couple of cases where I could hear a constant digital sample and hold sound in the surrounds. It wasn't in the 2-channel source but it was really apparent in the surrounds. It sounded like that phased, swooshing sound one hear when someone tries too hard with one of those spectral center extraction plugins, only worse!

Anyway, I'll check it out. The software is limited to Dec. 2006 and there doesn't seem to be any mention of what, if anything, will be available after that.

[raquete]

As a rule, I'm not a big fan of MP3s other than as a convenient compression format for my portable player. For surround work, I always try to stick with lossless source files. I can hear the difference in clarity between MP3s and lossless even at higher bit rates. It's more a matter of dynamics in the highs than anything else. Cymbals, etc., just don't breathe as well. They sound constrained and squashed.

my truly but dangerous comments about mp3 (fans excuse me) :
this is the first time that i read the true about mp3 in the internet(in thousands forums and places).
is exactly how i think and feel hearing... "it". (i don't like of ilusions)

your comments deserve a sticky in the top of the audio forum!

[NorthPole]

@ursamtl and @raquete

Thank, I didn't catch the software limit date.

Just looking for different options on upmixing movie soundtracks. Currently captured in stereo mp2 mode.

Unfortunately, I take a quality hit on the capture and decode from mp2 to wav and then I upmix from there.

Haven't struck on anything yet but will keep looking for better methods.

I like your vst plugins very much but I don't have plogue. The 3 step free method with foobar works good but is somewhat time consuming.
Btw, for AC3, if you use the aften encoder instead of ffmpeg or soft encode, you don't have to use wave wizard to remap the channels. However, you still have the issue of 3 different files to merge.
Still, very good results in the end.

[tebasuna51]

Originally Posted by NorthPole

Btw, for AC3, if you use the aften encoder instead of ffmpeg or soft encode, you don't have to use wave wizard to remap the channels. However, you still have the issue of 3 different files to merge.

With new AviSynth v2.5.7 RC-1 the WavSource() accept 32 bit Float and the wav output can be 32 bit Float, then the best method to ac3 encode may be with a Merge32.avs:

global OPT_AllowFloatAudio=True
f = WavSource("D:\YourPath\x_fLfR.wav")
c = WavSource("D:\YourPath\x_CLFE.wav")
s = WavSource("D:\YourPath\x_slsr.wav")
MergeChannels(f, c, s)

And after:

bepipe --script "Import(^D:\YourPath\Merge32.avs^)" | aften.exe -b 448 - x.ac3

[raquete]

another great post (or fast tutor) tebasuna, is bookmarked!


thanks!

[NorthPole]

@tebasuna51

Good idea...Thanks.

[NorthPole]

@ursamtl

Do you know of any vst host programs that can create the 3 different stereo wave files from a command line in a batch file?

I was thinking about trying to generate the 3 different wave files with your plugins within a batch file and then pipe it into an encoder.

[ursamtl]

Unfortunately, to my knowledge, there are no command line hosts. I had a similar idea a few months ago and did a search around the internet. There are various commandline programs for merging or splitting 3 stereo waves once you have them.

[NorthPole]

@ursamtl

Thanks for the reply...I kind of thought it was a long shot.

[ursamtl]

Yeah it's too bad. I thought I read somewhere something about AVISynth supporting VST plugins and thought that would be fantastic but I couldn't find anything else out.

[newhaven]

hi,
is there a way to get more bass out of each channel using this method, or even just the lfe channel?

any ointers or lessons are appreciated-----newhaven

[ursamtl]

You can always use EQ, but one of the best ways to increase deep bass is to compress the bass. If you can find a free multiband compressor, try compressing just the bass frequencies. As with all effects, do it subtly. A little bit goes a long way. Then leave it and come back the next day to see if it still sounds good. Ears tend to become less sensitive as we work on audio on a given day and we all tend to boost or cut things more than necessary. Then the next day, what sounded good one day sounds bad the next.

[raquete]

one of the best ways to increase deep bass is to compress the bass. If you can find a free multiband compressor, try compressing just the bass frequencies.

Steve,
seems very interesting but i don't understood how to do and basses are my "beach"...cool basses=cool sound,i like so much.
could you explain me in simple words? (if possible)

[newhaven]

steve,
when you are compressing the bass frequencies, at which point in the process that started this thread , are you doing so? also can you recommend a multiband compressor, free or not?
thanx --newhaven

[ursamtl]

Here are some free mulitband compressors.

http://www.kvraudio.com/get/1413.html
http://www.kvraudio.com/get/1360.html
http://www.kvraudio.com/get/1047.html
http://www.kvraudio.com/get/950.html
http://www.kvraudio.com/get/2000.html

You could try compressing the bass in the original stereo source file, or else the front L and R. You could try splitting the CLFE file and compressing the LFE channel only. This will give you a bit of really deep bass. If I had more time, I'd write a guide, but unfortunately, I'm very busy with my work right now.

Regards,
Steve.

[newhaven]

steve,
thanx for the pointers--will play on my own.

newhaven