GUIDE: Stereo to 5-Channel Surround

[Eye of Horus]

A GUIDE TO MAKE 5 CHANNEL SURROUND FROM STEREO
+++++++++++++++++++++++++++++++++++++++++++++++

This method provides excellent results. In some aspects it even sounds better than AC3 files ripped from DVD. Give it a try and share your thoughts with us !

Here is the software you need.....

- Cooledit
(http://www.syntrillium.com/download/)
- Aurora plugins
(http://www.ramsete.com/Aurora/download/)
- Tools Ambisonics
Included here - see below message

The Tools include 3 wav files you need further in the process and the free programs pack2x2to4.exe and ambidec.exe.

-> a B format signal is a 4 channel signal. W is the sound pressure. X, Y and Z are the harmonics on the pressure field. X is a vector directly in front of the listener, Y is a vector on the side, and Z is the vector of height. Since we'll decode a 2D signal (remember, surround is not 3D audio, it is 2D!), we can forget about the Z signal.

-> The goal here is to convert your stereo CD signal, which is UHJ - encoded, into a B format signal, which carries all the data so that you can decode all the channels you'd want to.

Okay, let's start working !!

-> Rip a stereo track from a CD

-> Using CoolEdit and Aurora, do this.

-> Start CoolEdit.

-> Load the UHJ-W filter file ,a 44.1 Khz file . Copy it to the windows clipboard. Press CTRL+6 for Windows Clipboard and the CTRL+C to copy to that clipboard.

-> Load the stereo signal (the ripped stereo track you want to convert).

-> Launch the "Convolve with Clipboard" Aurora module, and set the following settings:

Channels to convolve: Audio data: Both. Imp. Res: Both. No Crosstalk cancel mode. No remove DC component. No autorange result. No timeReverse Imp. resp. Gain =0.

-> Convolution begins. When it ends, you'll have a stereo file. We need it in mono.

-> Convert Sample type, from Stereo to Mono, with a 50% mix on each channel and 32 bit resolution.

-> Close and restart Cooledit. This is necessary to be sure that the clipboard is empty again ! Make sure you set the Windows clipboard (CTRL+6)

-> Repeat the procedure, but load the UHJ-X and UHJ-Y files, so you end up with three mono files (which will be your w, x, and y signals).

-> Now remember, the "Z" component means "height". So we really don't need to decode it.

-> Close and restart Cooledit

-> Now we have to pack the W signal along with the X signal.
Re-transform W in a stereo wave file, with 16 bits depth, using the Convert Sample Type module in Cooledit. Be sure 100% of the signal goes to the left mix, 0% to the right, and that resolution is 16 bits. Enable dithering.

-> Now switch to the X signal (the X file we've been working on). Resample it to a 16 bit mono file and Copy it to a Cooledit Clipboard. Go back to the W signal, select the entire right channel and paste the X signal file into the right track of the W stereo signal. You'll end up with a stereo file with the W signal on the left channel and the X signal on the right channel. Save it !

-> Close and restart Cooledit

-> Switch to the Y signal. Convert it to stereo, 44.1/16. The Y signal will be 100% on the left channel. Since we don't have a height (Z) signals, the right channel signal should be left empty. Save it !


-> Now you have two stereo signals. Change the extension of the WX file (should be WAV) to "WX". Change the extension of the YZ file (should be WAV, too) to "YZ".

-> Run the Pack2x2to4.exe file from a DOS prompt. It will ask you the names of the WX and YZ files. It will then save a 4 channel WXYZ file suitable for use with AmbiDec.
! So make sure the extension of the saved file is .WXYZ

-> Use ambidec. It's a program that is used to decode a B-Format file (the one you made) to produce a Wave file with speaker feeds. Those files will be suffixed in .wxyz.
You can decode the signal into any rig type. If you are using a standard 5.1 system, you'll want to decode it in "Pentagon".

-> Use it like this:

ambidec -r Pentagon (input file) (output file)

-> The file you'll end up with is a 5 channel wave file. Now we must encode it to DD 5.1
Load the entire file into SoftEncode. The program automatically recognizes the feed as a 5 channel wave file, and presents it as such. Encode it with a setting of 640 K/s to get the higest possible quality in DD5.1 .


-> Burn the result and enjoy ! The results are really superb !!

OR

Use Bspilt to extract 5 wav files from the wxyz signal and use Surcode DTS to make a DTS.

Commandline for Bsplit :
besplit -core( -input song01.wav -prefix g:\song01 -type wav -demux )

song01.wav = song01.wxyz
g:\song01 = the place where the 5 mono wavs are saved

Use the files in this order :

Left front : song0101
right front : song0103
center : song0102
lfe : stays blank
left surround : song0104
right surround : song0105

NEW METHOD FOR THE LAST STEPS
=============================

After making the wxyz file, there is now an alternative for Ambidec and Besplit. My friend Andreas brought this goodie to my attention !
First the link where you can download the program VVMIC, which stands for Visual Virtual Microphone.
http://mcgriffy.com/audio/ambisonic/vvmic/
Download, install and run the program.
Here follow the steps :
1. Click on input file and chose your wxyz file. You can chose between a wxyz extension or a wav extension.
2. Click on output file and give it a name
3. Select multiple mono files
4. Change number of outputs to 5
5. Select link pairs and select all directives
6. Click on G-format
7. Now click on PLAY and you will end up with 5 mono files !

In surcode, use the same order to make a DTS from those 5 files as described above (1-3-2-blank-4-5)

Results are a fraction less then the Ambidec/Besplit method, but that's mainly, because there is no gain control. The volume is lower and it sounds a little bit les crispier, brighter.

But.... it is very easy and saves a lot of time and it is very fast !



Good luck and let us know something about your results !

Eye of Horus with the much appreciated help of Dr. Freudiana

DSPguru : We hope you will be able to include this

[theReal]

I have one naive, amateurish question about this :)
If the source is stereo, why is the result going to sound better as a 5 channel file?

Is the result just like if I'm telling my 5.1 soundcard to play stereo files on all channels (and apply some spatial effects, maybe)?
But, there must be a benefit over this, otherwise you wouldn't go through all the hassles, right?

[DJ Bobo]

@ Eye of Horus
This is all very nice, but even without testing (I don't have a 5.1-system), I can tell you, you won't get real 5.1 sound. I think, as theReal said, you're just applying some kind of surround effect, nothing special. I think it works in a similiar way like Dolby Surround Pro-Logic II.

But I will take the opportunity and ask you about something really impotant for me: how to generate high frequencies from a source that have frequencies up to 11KHz only in a good quality?
I remember someone having asked such a question but there was no good answer I think. You seem to be an expert in sound matters, so may be you can help :D

[Eye of Horus]

Originally posted by theReal
I have one naive, amateurish question about this :)
If the source is stereo, why is the result going to sound better as a 5 channel file?

Is the result just like if I'm telling my 5.1 soundcard to play stereo files on all channels (and apply some spatial effects, maybe)?
But, there must be a benefit over this, otherwise you wouldn't go through all the hassles, right?

Of course there is !
I suggest you read this article :

http://s2n.org/Articles/Ambisonics.html

It is a complete explanation and it also gives inside why this system never made it to the mainstream. It was invented in the 70's !!
And.... all experts (I am definitely not !) say this is the best !

just give it a try once and then you will know why !

best wishes,

Eye of Horus

[Eye of Horus]

Originally posted by DJ Bobo
@ Eye of Horus
This is all very nice, but even without testing (I don't have a 5.1-system), I can tell you, you won't get real 5.1 sound. I think, as theReal said, you're just applying some kind of surround effect, nothing special. I think it works in a similiar way like Dolby Surround Pro-Logic II.

But I will take the opportunity and ask you about something really impotant for me: how to generate high frequencies from a source that have frequencies up to 11KHz only in a good quality?
I remember someone having asked such a question but there was no good answer I think. You seem to be an expert in sound matters, so may be you can help :D

Oh no !! I am definitely NOT an expert !
But... I did some reading on the subject (a lot).
In one of my first posts I asked if people could help me on this subject ! A friend promised me to tell me how to do it, but after 6 weeks I almost gave up hope. And.... today the instruction finally was there :-)
I immediatly tried it with an instrumental from my favorite group (the Alan Parsons Project) and I still have that feeling....this can't be true !! But....it is :-)
So no "expert" opinions here. The only thing I will say about it, is that it is NOT like Dolby at all ! If you wish it can even encode to surround from 10, 11, 12 or whatever number of speakers !

I know we always take for granted that true surround is : a solo guitar from the left-front, voices from the Center, Bass thru the LFE, etc.etc. The article will give you a complete different angle !

http://s2n.org/Articles/Ambisonics.html

It tells all !

Just read it !

best wishes,

Eye of Horus

[MvB]

@eye

If i'm not mistaken you need for correct reproduction of ambiosonic sound a special microphone. the standard stereo signal (please correct me if i'm mistaken) doesn't include enough information to build the ambiosonic matrix. At least you would need two microphones placed orthogonal together while recording to include the sound comming from the back? I've just had a short peek at the paper you indicated but they talk about a special microphone for the recording. Even if you throw out the height ... if i understood correctly a normal stereo signal is not really a useable source. But maybe i've misunderstood the whole thing.

[Eye of Horus]

Originally posted by MvB
@eye

If i'm not mistaken you need for correct reproduction of ambiosonic sound a special microphone. the standard stereo signal (please correct me if i'm mistaken) doesn't include enough information to build the ambiosonic matrix. At least you would need two microphones placed orthogonal together while recording to include the sound comming from the back? I've just had a short peek at the paper you indicated but they talk about a special microphone for the recording. Even if you throw out the height ... if i understood correctly a normal stereo signal is not really a useable source. But maybe i've misunderstood the whole thing.

For live-recordings : yes, a special microphone is needed.
And indeed normal stereo hasn't enough information.
That's why we convert it ! :-) The 3 pulse files add room characteristics to the stereo sound.
Just try it out, the results will amaze you !
I still cannot believe the results ! I did a few other tracks and still every track sounds very good.

best wishes,

Eye of Horus

[theReal]

How do you play it back? Do you have a DVD Burner and play it through your DVD Player?

[Eye of Horus]

Originally posted by theReal
How do you play it back? Do you have a DVD Burner and play it through your DVD Player?

????
It is a standard WAV file ! You can burn it to CD, just like WAV's encoded with DTS.......
So I burn it to CD and play it on my standalone DVD-player...... I don't have a 5.1 card in my PC :-(

Eye of Horus

[theReal]

I don't have a standalone DVD player, so I didn't know you could play DTS wave files from normal CD's. I thought you had to have an Audio-DVD to do that.

[Eye of Horus]

Originally posted by theReal
I don't have a standalone DVD player, so I didn't know you could play DTS wave files from normal CD's. I thought you had to have an Audio-DVD to do that.

They are just normal wavs, but of course you need an decoder to hear them. A normal cd player attached to stereo only gives white noise when you play these. And yes, when you have a 5.1 card in your PC, you should be able to play them.....

Eye of Horus

[Eye of Horus]

Originally posted by Eye of Horus


Tomorrow I will start trying to make a script or batchfile to automate the process in Cooledit..... (never done that, so cannot promise anything !)


Well, I tried and tried and tried :-(

There are a view problems in Cooledit. I will write them here and also edit the guide. It is important to follow these line to be sure you will get good results !

1. A script in Cooledit is useless ! You still have to be at your PC because you have to press "Enter" or "OK" for quite a few times. So that's not a real solution....

2. IMPORTANT !!!!
Cooledit has some major problems with the clipboards.
a. When you are in one of the first steps in the guide, you have to put the UJH-x.wav in the WINDOWS clipboard. Do NOT use one of the Cooledit clipboards !!
b. When you are finished with the UJH-x part, then close Cooledit and restart the program. Make sure to clipboard is set to Windows and is EMPTY !
You have to do this, because I found out that when you copy to the clipboard, the second time you do this, the first content isn't always correctly removed. And I couldn't find an "Empty Clipboard" function. So that's why it is absolutely necessary to restart CE !
c. When you try to do several steps at once, like Convolve with clipboard, then immediatly conversing to MONO 32 bit and then conversing to Stereo 16 bit. When you have done this for the W-wav...no problem ! But then you must Save the file and restart CE.
d. When you have done X-wav....Save too ! And....restart.
e. When you want to combine W and X, make completely sure that when you are copying X-wav to the clipboard, that you have one of CE's clipboards and NOT Windows' clipboard.

A tip : when you want to convert a whole cd, it is fastest when you load in all the wavs and one of the UJH-.wavx, and do the steps involved with all the files. Then save them all, restart CE and to the next step...... This way it saves you a lot of restarts and reloads... !!!


Another thing is the order of the WAV files as given in the DD5.1 encoder : Leave it as it is. ! It looks unnatural in the graphics in the DD5.1 screen, but it is NOT !!

When you use Bsplit to make five separate MONO wavs from the 5_streams_wav, you end up with lets say track01_01.wav, track01_2.wav, track01_3.wav, track01_4.wav and track01_5.wav.
This is the correct order for using them in Surcode to make a DTS :

Left Front : 01-1
Right Front : 01-3
Center : 01-2
LFE : left blank
Left Surround : 01-04
Right Surround : 01-5

Yesterday I did Water Colours and Seen One Earth from Pete Bardens.
And.... the results were SUPERB !
Full natural surround in DTS ! When you really want to hear what this whole method is about : use the DTS encoder instead of the DD5.1 encoder ! The sound is just more...fresh, clear, bright .

In the beginning some people asked if it really is worth the troubles and time. I can really say : YES ! After experiencing that sound, I understand more what I did read on the Internet about it !


Anyone else tried it yet ?

Last point : someone asked about the microphones to record. Well, there are quite some UJH encoded cd's available. As you can read in the article (link in the "guide") the writer quotes a review of "Stereotomy" by Alan Parsons. This is one of the UHJ encoded cd's. This one sounds excellent when you listen to it in stereo.And those who have read the article : all the channel information you need for whatever number of channels is already in that file ! So when you do the complete process on this CD, you get the ultimate result. Full perfect surround which throws a huge shadow on whatever other surround system !!!!!

I am not an expert on this, I only believe my ears ! They don't lie to me......
I found a list with a few titles online and will do a search if they are still available .


Well, we still need a bit more automated process. Is there any way (DSPguru?) to put the two DOS programs from the Ambisonics package and the Bsplit program in one ? So all the steps from thesong.wxyz file to 5 separate MONO wav files ??

I will adjust the guide later........ this was long eough for now :-)

best wishes....... and please share some reviews !!

Eye of Horus

[DSPguru]

Originally posted by Eye of Horus
Is there any way (DSPguru?) to put the two DOS programs from the Ambisonics package and the Bsplit program in one ? So all the steps from thesong.wxyz file to 5 separate MONO wav files ??i can surely implement the 'Pack2x2to4.exe' part inside BeSplit. i belive my code might even be faster.
as for ambidec,
since i don't have time to dig into this, i would have to ask you for direct links for info about its operation, algoirthm, etc'...

then, i'll see what i can do.. :)

[Eye of Horus]

Originally posted by DSPguru
i can surely implement the 'Pack2x2to4.exe' part inside BeSplit. i belive my code might even be faster.
as for ambidec,
since i don't have time to dig into this, i would have to ask you for direct links for info about its operation, algoirthm, etc'...

then, i'll see what i can do.. :)

Here is the link to the site of the maker :

http://www.muse.demon.co.uk/mn_index.html

regards,

Eye of Horus

[ivan_alias]

Is there any other way to do this at all that may be easier?

I'm going to give this a go with some Michael Jackson, but the process is quite a long one!


I want to thanks Eye of Horus for his / her hard work on this though! I don't want to seem ungrateful :)

[Eye of Horus]

Yes , there is a faster way to do this, but the results are worse.
There is a commercial available program, that does basically the same but without use of Aurora or Cooledit. It's all done in one program and IMHO it's main drawback is that it doesn't do any resampling with 32 bits, but it does all with 16 bits files. The endresult is the same but it sounds more dull, flat. Just like when you convert a 44.1/16 to a 22.050/8 wav.
The program is for sale but you can ask the maker by email a key for 30 days.

The FIReverb Suite 2nd edition
Available at : http://www.catt.se

I know my method is very timeconsuming, but it gives good results !

regards,

Eye of Horus

[jansb000]

In the guide you tell us to use SoftEncode to change the 5-channel wave into DD5.1. According to the documentation this task could be done with BeSure. Have you tried this?

(BeSure is free - SoftEncode is not and seems to be no longer available on the web)

PS: In another post from me I mention problems with BeSure, but for the time being I guess that these problems are caused by wrong parameters that I set and not by a real problem with the tool.

[Eye of Horus]

When you use Besure....... at the end it starts.....Softencode !!!!

Contact me private at my email address !

regards,

Eye of Horus

[DSPguru]

Originally posted by Eye of Horus
When you use Besure....... at the end it starts.....Softencode !!!!no, it doesn't.
BeSure uses BeSweet to encode to DolbyDigital & uses SurCode to encode to DTS.

[Eye of Horus]

You're right !
I mixed up Softencode and Surcode :-)

BTW did you shine your light on implementing pack 2x2to4 and ambidec ?

It would be marvellous !!!!!

regards,

Eye of Horus

[iGorland]

Just wanted to say: Thanks! It does take time to go through the whole procedure for one CD, but the DTS sound at the end is great on my CD player with optical output!

[kempfand]

@ DSPguru:

Just also want to say that I look forward to the ambidec implentation.

I also like the sound, and some automation will help alot.

Regards,

Andreas

[DIggedy]

Use the files in this order :

Left front : song0101
right front : song0103
center : song0102
lfe : stays blank
left surround : song0104
right surround : song0105



Why is there no LFE file? I'd imagine adding an LFE channel would just be a matter of using left front & right front converted to mono followed by a low pass filter... I have my own method of creating 5.1 conversions using only Sound Forge and have not tried this method yet... am interested to see how it compares.

[lucindrea]

i'm curoius on how you do your 5.1 ...
i can take a stero file and make a mono for center and lfe .. just cant figure how to remove the center from the left and right .. also the dynamics of the rear are hard to get working also

[drpaulng]

If what the soundforge's impulse (delay effects) has already done with close simulation to various environments. Why bother use this AURORA thing when the CoolEdit Pro plug-in costs 200USD with so slow in multiple steps to simulate Ambisonics?

[Eye of Horus]

Originally posted by drpaulng
If what the soundforge's impulse (delay effects) has already done with close simulation to various environments. Why bother use this AURORA thing when the CoolEdit Pro plug-in costs 200USD with so slow in multiple steps to simulate Ambisonics?

And what does SF cost ?????

You forget there is a difference between reverb only and Ambisonics (read the websites). And only adding reverb doesn't convert your stereo to 5.1 DTS !! And it doesn't simulate ! It IS Ambisonics !
Yes, it simulates the room responses, but that's not the only thing it does !

Take for instance the program from www.catt.se .
You can make 5.1 from stereo with added reverb. Simple direct way. Why do you think they included a separate option to encode to Ambisonics ????

Eye of Horus

[DSPguru]

Originally posted by kempfand
@ DSPguru:

Just also want to say that I look forward to the ambidec implentation.

I also like the sound, and some automation will help alot.

Regards,

Andreas if i only had more free time.. :(

[drpaulng]

Can you show us a sample to convince us to spend 200USD for the plug-in. I lost interest after the non-registering bomb. How can ambisonics be evaluated when we never get in touch with it? We've got no idea or any impression on this technology at all. With a good AV amplifier such as the DENON 3802, one can get instant surround simulation with DTS NEO 6, Dolby Prologic II, and even one more, called DENON 5 or 7 channel stereo. I call all of them simulated surround because it is true that the multi-channel sound is generated from a stereo source. If you give me a chance to use the original multi-track recorder, I'll make my own version of "true" surround by feeding some of the tracks discretely like the new DVD Audio such as the Eagles' Hotel California. The DENON 5 or 7 channel stereo is the closest simulation to the DVD Audio 5.1 sound, for example, Fleetwood Mac's RUMOURS is a very good example when you feed the stereo in and get the DENON 7 channel out. A brief listening moment would fool you into believing that you are hearing from the 5.1 mix. If DENON can give us their simulation surround like this, why doesn't the AMBISONICS? Just go license such DSP firmware to all kinds of brands of AV amplifier. We just can't bear to see such good thing buried dead...but please, at least let us have a slight touch on this. Show us an .ac3 file sample please.

Sound Forge 6 is 349.97USD (I just checked this on the web).
Cooledit Pro 2 is 249USD...and the AURORA plug-in package is 200USD.

[Eye of Horus]

Originally posted by drpaulng
Can you show us a sample to convince us to spend 200USD for the plug-in. I lost interest after the non-registering bomb. How can ambisonics be evaluated when we never get in touch with it? We've got no idea or any impression on this technology at all. With a good AV amplifier such as the DENON 3802, one can get instant surround simulation with DTS NEO 6, Dolby Prologic II, and even one more, called DENON 5 or 7 channel stereo. I call all of them simulated surround because it is true that the multi-channel sound is generated from a stereo source. If you give me a chance to use the original multi-track recorder, I'll make my own version of "true" surround by feeding some of the tracks discretely like the new DVD Audio such as the Eagles' Hotel California. The DENON 5 or 7 channel stereo is the closest simulation to the DVD Audio 5.1 sound, for example, Fleetwood Mac's RUMOURS is a very good example when you feed the stereo in and get the DENON 7 channel out. A brief listening moment would fool you into believing that you are hearing from the 5.1 mix. If DENON can give us their simulation surround like this, why doesn't the AMBISONICS? Just go license such DSP firmware to all kinds of brands of AV amplifier. We just can't bear to see such good thing buried dead...but please, at least let us have a slight touch on this. Show us an .ac3 file sample please.

Sound Forge 6 is 349.97USD (I just checked this on the web).
Cooledit Pro 2 is 249USD...and the AURORA plug-in package is 200USD.

Ok... a reply....
First of all I want to state two things.... English is not my native language. I'm from the Netherlands and only learned English in highschool, which is about 30 years ago. So : sometimes you need to read between the lines. OK ? When something is not quite clear, please ask me to rephrase and don't start to yell immediatly ! :-)
Second : I don't want to be dragged in a role where I have to defend something and where you are the attacker. I don't like Mac<>PC wars, I don't like Quad<>DD5.1 wars, I don't like LP's<>CD's wars !

I wanted to understand more about surround in general and I decided to do a search on the Internet. I have read a lot about Quad, Dolby, DTS etc. I am not an expert in DSP, I am not an expert in whatever soundprocessing and I am certainly not THE expert to explain the advantages of Ambisonics. I don't even know if I can do that with my knowledge of English, but I try......
After reading a lot, I asked a simple question in an Audio Newsgroup : How can I make 5.1 from stereo ?
I got several reactions and some were just like yours : use your hardware ! Well, I got a nice Yamaha receiver that got excellent reviews from users all over the world and especially they liked the excellent DSP built into it. I can emulate 5.1 with it and yes... it sounds like real 5.1. Just like you say about the Denon.
But.......... I don't like 5.1 and I don't like quad. I always had that feeling of something missing in both. As I already stated : I am NOT an expert, I react only by my own feelings, by what I hear and try to explain it as simple as possible. Quad : this has IMHO nothing to do with surround, it is just extended stereo. And in some mixes it is terrible. A drummer from the left front channel, a singer from the right front channel, a guitarplayer from the left rear and a bass from the right rear. But..... where the heck is the band ?????
In quad they sometimes overact the separation of the channels. And this brings you to another thing missing, which will come back in the 5.1 mixes and I will discuss that later on in this reply.
5.1 : I am very disappointed with a lot of music in 5.1. Comparing it with quad, it is at least more surround, but most of these mixes suck. There are only a few producers who use that format to the limit and one of them is Alan Parsons with his DTS version of "On Air" . IMHO still the best available 5.1 mix.
As you know, the DTS catalog is small..... I've heard a lot of the original DTS cd's (and then I mean the music that was officially released on DTS !). Nothing comes close to "On Air"
For movies however, 5.1 is excellent ! I love the way some of the producers give you the feeling you are "in the movie". I DID dive in some of the scenes of "Saving private Ryan", because I got the impression someone was shooting at me from behind :-)
Back to music however, there are not that many 5.1 mixes (DD or DTS) that do something extra to the music. A lot of these can be heard in stereo without losing much of the effect. Why? Because on most tracks there is no effect ! There isn't hardly any music that in 5.1 gives you the same sensation as some movies do ! I hope I have put this part in an understandable way in words !
So obviously there must be something wrong in quad and 5.1 .
And here I come on to what that is : the Sweet Spot.
Quad and 5.1 can only be appreciated fully when you sit on the sweet spot and your room is capable of placing the speakers where they SHOULD be ! Is that surround ? One spot in your room where you can fully enjoy it, but moving one meter to the left or right and away goes the good effect ! Is that surround ?? I don't think so !
In my definition surround means you are surrounded by sound. Sound coming from everywhere... And that's not the case with quad or 5.1 ! Oh, so they say : then we just add some more speakers. 6.1 , 7.1 , 8,1...... where the heck does that stop ????
And here I come back to the DSP's in receivers : yes, some do an excellent job and give you the feeling you are listening to 5.1, but the above mentioned disadvantages still are there. And there is also another thing to keep in mind : not everyone has the ability to spend huge bucks ! Not on hardware and.... not on software. that's why a lot use illegal software , but illegal hardware ??? LOL !! It is not there !! So a lot of us stick to the cheaper range of the "surround" sets. And.......... get disappointed ! You will be surprised to know how many people there are with complete surround sets, cheaper than one piece of Soundforge !

Ok, back to where I was :-)
So because I was disappointed, I looked further and then someone pointed me to Ambisonics. I visited all the websites available and read all about it. I didn't understand more than half about the mathematical explanation, I didn't have a clue about recording, but as these were university professors, I believed them. I had no reason and not the knowledge to judge their opinions ! But what I did understand out of all these websites, was that there was a system that could give you REAL surround. A system where it didn't matter if you moved one meter from the sweet spot. I was impressed and needed to give it a try. And I did.... but only after I got in contact with another Alan Parsons fan who pointed me to a review of AP's album "Stereotomy". Woowww, Alan recorded that in Ambisonics and the reviewer was very enthusiastic about the sound in stereo. (We are talking vinyl here !!! not CD !!!) This reviewer (and he was not the only one) said he had never heard an album which such a clear sound that gave you the impression of some sort of surround. (Mind you : we are still talking about stereo vinyl !) So I thought : if such a big producer ("Dark side of the Moon" ! and all the Alan Parsons Project albums) already used a system in his recording in the beginning of the 80's that gave a critic reviewer a sense of surround and this same producer now made the only reasonable DTS cd...then I just have to try it ! If he does it, it can't be wrong, huh ? Of course I am biased : I am a fan !
Ok, that same guy gave me instructions on how to do it and with his help I developed the guide as published here.
And now comes the difficult part for me : explain the difference between Dolby Digital and DTS and Ambisonics. Well, I tried above a part and only can add here this : the "sweet spot" in ambisonics is a lot bigger than whatever other surround system. Ambisonics is not based on separation of channels. Recordings with only two Ambi compatible microphones contain all the information ! You don't need 5 or more microphones.
And as Stereotomy was recorded with Ambi compatible mics : a conversion to DTS (actually : 5.0) was just the next logical step.
And boy oh boy.... it sounds so good ! There is only one judge here : my pair of ears ! They won't lie to me ! They don't try to convince me what is a better format, they just let me listen to music and decide for their own what I like most !
OK, so I converted a stereo to DTS (5.0) and it sounded superb ! But...that stereo already had all the information in it because it was originally recorded with Ambi mics. So I searched further and found out that you can emulate that kind of recording by adding "roompulses" to the stereosound and encode it to Ambisonics.
And so I came to the final guide !

Ok, that was the history and the reason behind it, now of course you want to hear a sample ?

Tomorrow I will publish somewhere online one sample that you can play on your set. I will give you the address tomorrow. It will be a conversion from a stereo track to a DTS track. Just burn it on a CDRW and play it. If you don't like the music.... don't let that stand in the way of the experience of REAL surround.

Is this now the ultimate soundexperience in surround ? No, it is not ! Ambisonics has some disadvantages too ! I believe (Note : I am not technical, only repeat what I understand from what I've read) it also works with differences in soundpressure. And these differences sometimes lead to an effect where instruments are floating between speakers. I cannot explain this in English :-( Something like someone is singing and you hear his voice in one speaker and one thousand of a second later in another speaker and then back again...
So not every music has the same great effect ! It works better when the stereo signal already had a clear separation and it definitely works better with symphonic music and music where sound is already in stereo floating from left to right or with sound that has a lot of pressure. (Pink Floyd, Yes, ELO, Alan Parsons, Techno, House !)
it works worse on music like traditional rock or music with only a few instruments (For instance a singer with an acoustic guitar. But hey : does that work good in Quad or DD or DTS ??)

Well, it was a long reply.... tomorrow an example !

good night.........


Eye of Horus

[Eye of Horus]

Ok, I promised a track .
It is a 7 minute wav-file. just burn it on a CDRW, so you can always delete it :-)
(DON'T FORGET : IT IS DTS, SO ONLY PLAYABLE WHEN YOU HAVE A DTS SYSTEM !!!)
It is about 77 MB, so I had to place it on 2 different servers.
Use Winrar3 to extract the wav.

Here are the links :

http://thor.prohosting.com/miempie/Track06.part01.rar
http://thor.prohosting.com/miempie/Track06.part02.rar
http://thor.prohosting.com/miempie/Track06.part03.rar
http://thor.prohosting.com/miempie/Track06.part04.rar
http://thor.prohosting.com/miempie/Track06.part05.rar
http://www.xs4all.nl/~appfan/Track06.part06.rar
http://www.xs4all.nl/~appfan/Track06.part07.rar
http://www.xs4all.nl/~appfan/Track06.part08.rar
http://thor.prohosting.com/miempie/Track06.part09.rar

BTW.... they won't be there forever !!!

March 20, 2003 : REMOVED THE TRACKS.

So download them as soon as you can......
And..... give us your comments here !!

best wishes,

Eye of Horus

[lucindrea]

hmm .. slight problem on this end ... and this may or may not be the fourm for it but here goes
i have a audigy gamer connected to creative's inspire 5700 speakers connected via spidif out and i have the card to send eveything digitaly ... anyone know how i can listen to DTS tracks? the 5700 has the dts logo on it .. the thing does great with DVD's , i just cant get anything with DTS to play anything but white noise ... acctully an ac3 plays fine unless it has the wav ext. needed for cda then it's also noise.

[MaTTeR]

Originally posted by lucindrea
i just cant get anything with DTS to play anything but white noise ...
Most likely it's because the card and/or driver is molesting the stream and then the amp isn't recognizing it as a "pure" DTS stream. Awhile back I ended up running a cable from the digital out connector on my CDROM to the amp directly in order to get around this problem. It's a solution but not a very pretty one. Think we have a few threads in the forum also discussing this as well....not sure how long ago it was though.

[Eye of Horus]

Did some reading.....
Problem is that it assumes a 48 Khz stream with DTS and the DTS on CD is of course 44.1 Khz.
You shouldn't be able to play an official DTS CD (www.dtsonline.com) too.

Don't know about how to fix it..... suppose you have to do some searching ! Some in alt.audio.dts had the same problem.......

EoH

[DIggedy]

i'm curoius on how you do your 5.1 ...
i can take a stero file and make a mono for center and lfe .. just cant figure how to remove the center from the left and right .. also the dynamics of the rear are hard to get working also


I've yet to work that out myself but don't mind just using the original stereo channels for Front L&R, I find it gives the front soundstage a 'presence' that still improves the sound. How do you create your LFE after converting to mono? I use the Paragraphic EQ to isolate the low frequencies.
I also know what you mean about the dynamics of the rears... what I do to help this is to use Paragraphic EQ on the original stereo file to isolate the lower end (about 80-60hz down) then Paste mix this signal into the rear channels.
If you guys are interested I might do a guide to my process... I'd be interested to see what others think of the end results.

[vvlad]

Hi
I should say that it is very interesting technology
but whe I've tried to do it myself I don't get superb result
it seems that I do something wrong

problem:
AC3 i've got and tried to play in WinDVD plays faster then source file
Does anybody get same problem?

[drpaulng]

It's true.
This Track06.part09 is right. I just made a mistake by looking at the file size alone. I'll listen to the track first. Thank you very much.

[drpaulng]

http://home.gigigaga.com.tw/paulng/Amisonics.pdf

Please refer to the above pdf document for my quick report on the issue. This report is made with a brief listening session with my first impression. I do appreciate what Eye of Horus has shown us all. But I am a little sketpical on the selection of stereo tracks for encoding because not every stereo tracks recorded into a CD is pre-encoded in ambisonics (just the same for Dolby Prologic). So I dig a little deeper and discussed in my report.

[Eye of Horus]

[QUOTE]Originally posted by drpaulng
[B]http://home.gigigaga.com.tw/paulng/Amisonics.pdf

Tried the URL for several times now, on several days. Cannot get any connection !

EoH

[arman68]

I have read the full thread and articles linked from various posts.

It is very exciting news and I cannot wait to try it out. Like you I have always been disatisfied with current surround technology and felt that something was missing. Maybe it comes from having worked as musician in various band, therefore knowing how music should sound from 'inside'.

The only problem I have is I cannot decode DTS, and many people are like me.

However my hifi can decode Dolby Surround sound. I am well aware there would be a loss converting the tract to dolby surround, but it should still preserve a great deal of the ambisonic surround mix. After all, from what I understand, the ambisonic process is more of a recording and encoding process than decoding.

Let me know what you think.

[Eye of Horus]

As long as it is DD5.1 > no problem !
But encode it with 640 Kb/s for the best quality.
And DON't reduce the rear channels with -3 DB (If I remember correctly, that is standard in softencode).
I prefer DTS only because it has a better sound (1536 Kb/s), but to say the difference is huge.....no !

BTW still wish that like most modern standalone DVD players can play MP3, they make a model that can play AC3 ! (like the SB does)


regards,

EoH

[drpaulng]

:confused: Don't know why people cannot see the pdf, I add another address here:

http://www.geocities.com/drpaulng/Amisonics.pdf
or
http://home.gigigaga.com.tw/paulng/Amisonics.pdf

Please refer to the above pdf document for my quick report on the issue. This report was made with a brief listening session with my first impression. I do appreciate what Eye of Horus has shown us all. But I am a little sketpical on the selection of stereo tracks for encoding because not every stereo tracks recorded into a CD is pre-encoded in ambisonics (just the same for Dolby Prologic). So I dig a little deeper and discussed in my report.

I have tried making some MONO to STEREO, then extended to 5.1.
DTS encoding is better than DD encoding, absolutely!

[Eye of Horus]

Originally posted by drpaulng
:confused: Don't know why people cannot see the pdf, I add another address here:

http://www.geocities.com/drpaulng/Amisonics.pdf
or
http://home.gigigaga.com.tw/paulng/Amisonics.pdf

Please refer to the above pdf document for my quick report on the issue. This report was made with a brief listening session with my first impression. I do appreciate what Eye of Horus has shown us all. But I am a little sketpical on the selection of stereo tracks for encoding because not every stereo tracks recorded into a CD is pre-encoded in ambisonics (just the same for Dolby Prologic). So I dig a little deeper and discussed in my report.

I have tried making some MONO to STEREO, then extended to 5.1.
DTS encoding is better than DD encoding, absolutely!

OK, I am glad that some of the original scepticism is gone !
But yes..... I tried to fool you and you didn't fall for it !
My compliments !!!!
The track was from the indeed with Ambisonics recorded stereo albumn from Alan Parsons "Stereotomy".
Well.... now a fairer test. This is from a normal recorded stereo CD where the Ambisonics is added with my software method. For all of you who are still hesitating if it is worth the effort and time !!
It is a track from Pete Bardens. A bit new age, but Bardens played and wrote the rock album "Keats", which was actually Alan Parsons but without the orchestra and synthesizers.
So try this track ! Because this is really the ultimate test !! A stereo track converted into B-format (the WX and YZ files) and encoded into DTS.

http://thor.prohosting.com/miempie/Track01.part1.rar
http://thor.prohosting.com/miempie/Track01.part2.rar
http://thor.prohosting.com/miempie/Track01.part3.rar
http://thor.prohosting.com/miempie/Track01.part4.rar
http://thor.prohosting.com/miempie/Track01.part5.rar

REMOVED the tracks on March 20, 2003.



Happy listening !

EoH

[drpaulng]

The song.rar's are not ready to be downloaded...again?

ftp://drpaulng.myftp.org/

Try these 2 files, one .mp3 (mono) the other one .ac3 5.1 channel. Compare the difference.

These files won't last forever...(like your files).

[specise_8472]

After fixing the bug in the Aurora Plugin that kept crashing cooledit I am very impressed with the results. I am playing around at the moment with adding the LFE channel into DTS encodes. I have found that if just isolating the low frequencies (85hz - 25hz) from the original track and using them does not work as for some reason the length is different, and surcode complains.

Anyway thank you for giving your time to come up with a way of doing this, will give me hours of pleasure.:)

[Eye of Horus]

Originally posted by specise_8472
After fixing the bug in the Aurora Plugin that kept crashing cooledit I am very impressed with the results. I am playing around at the moment with adding the LFE channel into DTS encodes. I have found that if just isolating the low frequencies (85hz - 25hz) from the original track and using them does not work as for some reason the length is different, and surcode complains.

Anyway thank you for giving your time to come up with a way of doing this, will give me hours of pleasure.:)

Interesting idea !
Let me explain : I had a subwoofer that was not amplified and couldn't use the LFE channel on the receiver. The receiver has the option to leave out the LFE and mix it through the 2 front speakers. Cables from the receiver to the left and right front channels went into the subwoofer and came out again. So the subwoofer got it's bass from the two channels. So in my situation it didn't matter that it was 5 channels instead of 5.1 !
Two days ago however, my new surround speakers arrived with an amplified subwoofer that has two options of connecting to the receiver. One is as I described and the other is to the LFE channel on the receiver. As the cables were lying there already, I made the same connection as I had with the old sub.
Now first my question : What's the best option ? This way of connecting or use the subwoofer with the signal from the LFE on the receiver ?

Ok, on to an answer or advice : You end up with 5 mono channels . Try the bass from those ! There shouldn't be a problem then I suppose with the length !
Don't forget you added something to the original stereo file (the roompulses !) during the conversion.

BTW I haven't tried it yet... it is just a suggestion (or speculation !)

kind regards,

EoH

[Eye of Horus]

Originally posted by vvlad
Hi
I should say that it is very interesting technology
but whe I've tried to do it myself I don't get superb result
it seems that I do something wrong

problem:
AC3 i've got and tried to play in WinDVD plays faster then source file
Does anybody get same problem?

See above the reply to Lucindrea

EoH

[specise_8472]

I have just tried your suggestion.

I mixed the left and right channels, after besplit, into a single mono file, then isolated the low frequencies. Surcode took this without a problem. The lfe is there and can be heard. Sounds alright. But on my sound setup, when no LFE present I think the amp automatically sends all low freauencies to the sub anyway. As a lot of music CD's give the sub (powered btw) a good workout.
I actually tried isolating the lows then convoled them with W (just a random pick) and added this as the Z channel. The result was interesting. There was a noticable increase in the sub response, but the drawback was that there was a decrease in the very high ranges.
I think ambi-decode notices more low and saturates the higher in response.

How did you come up with the convole files in the first place?

[Eye of Horus]

Originally posted by specise_8472
I have just tried your suggestion.

I mixed the left and right channels, after besplit, into a single mono file, then isolated the low frequencies. Surcode took this without a problem. The lfe is there and can be heard. Sounds alright. But on my sound setup, when no LFE present I think the amp automatically sends all low freauencies to the sub anyway. As a lot of music CD's give the sub (powered btw) a good workout.

I think I dig into the manual again !
I was afraid that connecting the sub to the LFE would lose bass when playing a 5.0 or 4.0 CD. Or put the bass in the front speakers !?
I hope some more people can shine a light on this......
BTW can you tell the exact steps you used, so I can add it to the guide ??


I actually tried isolating the lows then convoled them with W (just a random pick) and added this as the Z channel. The result was interesting. There was a noticable increase in the sub response, but the drawback was that there was a decrease in the very high ranges.
I think ambi-decode notices more low and saturates the higher in response.

How did you come up with the convole files in the first place?

Well, In the guide I told that I developed the method together with a friend . He supplied me with the room pulses.....

regards,

EoH

[specise_8472]

BTW can you tell the exact steps you used, so I can add it to the guide ??

1 - Take the left channel after besplit and turn it back into stereo 100% left.

2 - Take the right channel after besplit and paste it into the right channel of the stereo file you just created.

3 - Filters/FFT filter - make a custom filter that only allows the low frequency range you want to be isolated. Filter the file.

4 - Return it to a mono file and then use as LFE channel in surcode.

I played around with the lfe file a bit and found that if you use the Amplify filter on it, you produce a marked difference in the LFE responce. I LLLOOOVVVEEE having the floor shake/vibrate under foot in the lounge (concrete floor) (VIRUS DTS is good for this during the storm at the beginning). Try 200% amplification then go from there depending upon personal tastes and what the track is/should be?.

I am still experimenting with different approaches and will keep you imformed. As I said before - "hours of pleasure".

Cheers

[drpaulng]

With the aid of somebody great here in this forum, I finally get in touch with the ambisonic codec. I'll try to make another listening report comparing my method (not ambisonics) and the newly acquired ambisonics.

The sample I made a few days ago was derived from a MONO sound source. After generating a stereo image by the pan/expand filter in CoolEdit, the surround channels were generated by adding the concert hall effect with a large cut down of direct original compoents. A 0.02sec delay was added to make a sense of back/surround rebound. To complete the 5.1 mix (actually 4.0 should be alright) the center was simply a original mono with some cut in dB level, while the LFE is made from the center mono via low frequency filtering at 120Hz roll-off. The result was close to what is heard in the official production (only a short video clip). But I was still unsatified with my simple method. Hopefully, if the ambisonic codec works, I'll adopt this method. Before I start the ambisonic project, I would like to ask what is the environmental condition that the impulses (WXYZ) for the convolving derived from. I think it is important because different kind of impulses should make different ambisonic sounds.