Question about encoding ac3

[mikeye23]

Im new to encoding ac3 and had a question. I'm taking a 2 channel wav file and want to convert it to 5.1 ac3. Is this possible? Im using Softencode and after I encoded it, I opened the new ac3 file in Softencode and it didnt show any waveforms or anything.
Excuse my ignorance, but I just wanted to take this wav file and have it play over 5.1 speakers and not just be stereo and come out the front 2 speakers. Im I going about this the right way?


Thanks
mike

[dragoman]

Hi,

Sorry, but no. There is no way to make a 2-channel source into true 5.1 audio.

There is a way to play 2-channel audio on a 5.1 system, but in reality all that does is split the left and right channels into different speakers (so the left frong, left sattelite, and left center speakers all play the same stream, there is no "surround" effect that comes from true 5.1 audio).

The way to play stereo sound in surround (5.1) mode is simply to select 5.1 as an output...the reciever will automatically split the sound to the various speakers, and you will hear sound coming from each speaker, don't get me wrong. But it will not be true 5.1 sound, rather it will be like if you have 5 speakers hooked up to a regular stereo.

If you are confused let me know and I will try to explain better.

dragoman

[mikeye23]

Ok. Yeah, it doesnt have to be true 5.1, I just want to make sure that sound will be coming out of all the speakers and not just the front 2. Is there anything special to do for this or can I just encode the wav to ac3 and the 5.1 speaker system will take care of the rest? plus is there any special settings in
SoftEncode that need to be selected in order to make this happen?

thanks again
mike

[dragoman]

Hi,

Nothing you do to the wav file itself will affect the way it is played back (2ch or 5.1). The way to make sure that you are playing it back out of "all the speakers", set your output to dolby surround or dobly 5.1

Even if the audio source is not encoded in 5.1, the reciever (in this case, your 5.1 soundcard) will split the audio as long as it's output is to "5.1"

So encode it the way you normally do, and make sure the sound output ON YOUR MACHINE is set to Dolby 5.1, and you will get the results you want.

dragoman

[Tes]

Just thought I might clarify something here; mikeye23, you don't need to encode the wav file to AC3 to get the sound to come out of all your speakers during playback. The original wav file should work just the same. The only reason I can see to encode in AC3 is for use in a compressed movie (with full 5.1 channels) as there are much better audio compression choices available for music.

[dragoman]

Hi,

Of course Tes is right.

You should not have to encode a wav file to ac3 format just to mux to a movie.

In that case mp3 would be a better choice....the quality of lame set at high would be equal to the ac3 in this case, and take up far less space.

dragoman

[mikeye23]

Im actually making a wedding dvd and was converting to ac3 to save space and to make sure compatible with all set top dvd players, where as other audio compression methods may not be as compatible.
So, if I just encode the pcm wav file to ac3, it would be played out of all the speakers on say a Bose 5.1 surround system. So is there any special settings on SoftEncode or should I just use the defaults?

Thanks for the feedback
greatly appreciated

mike

[dragoman]

Aha.....

Now we see. Okay, yeah that should work. All standalone DVD players will be able to decode ac3 audio, that is a good plan.

The same theory applies. When the reciever of this setup is set to "Dolby 5.1" you will hear the sound out of all channels. You just won't hear the specific directional sound coming out of the rear speakers for example, the sound will be stereo sound.

How you encode the audio doesn't matter....

dragoman

[mikeye23]

dragoman,

appreciate your help.
thank you

mike

[dragoman]

No problem.

dragoman

[focker]

I am not understanding why you can't create a true 5.1 soundtrack when you have a wave file......I also have used Soft Encode and I open each wave file 3 times in the same project and it reflects 6 channels when it is encoded to an AC3 file.....my Pioneer system will automatically recognize the audio format and show what channels are playing.....when I put in a DVD that is in Dolby Stereo 2.0 it only reflects 2 channels....when I put in a DVD that I did in 5.1 all channels are reflected and have music playing from them. According to my home theater system it is a true 5.1 stream.....if what you say is true than could you please explain that a little more.

I have seen people also argue the point as to whether a stereo file is worth converting to 5.1.....I say it is because a) you save space on the DVD and b) I can hear a difference in a DVD that is created in DD 2.0 as opposed to one I create in 5.1. I would like to hear more on this as well....

Thanks!!!!!

[specise_8472]

Have a look at

http://forum.doom9.org/showthread.php?s=&threadid=29277

Cheers