Just curious about upconverted 5.1 with a couple of questions?

[Socio]

I have been reading a lot of the guides and posts here and have a couple of questions regarding Stereo to 5.1 conversions.

1, It seems a lot of you go through a lot of effort and expense converting rebook CD music audio or other 2 channel music audio to DD 5.1, DTS 5.1 etc...

I know you can't actually improve the resolution of the audio on a CD. So does going through the effort to convert 2 channel audio to 5.1 and listening to it that way really sound better than just using a receivers prologic to output 5.1?

If converted 5.1 does sound better is it the converting that does it or using a different DAC output due to the conversion that give the improved sound?

2, To those who are doing this, what is preferred for 5.1? 24bit @ 48Khz or 16bit @ 96Khz? Or is there even a noticeable audible difference?


One more

3, If you burn a Audio disc or DVD using BeSweet 5.1 AC3 as the audio format and then play it through a surround ound receiver what does the receiver see it as?

[E-Male]

i personalyl daubt that it's worth the effort when you got dlp2

but other people have other opinions

[daphy]

some answers:
I know you can't actually improve the resolution of the audio on a CD. So does going through the effort to convert 2 channel audio to 5.1 and listening to it that way really sound better than just using a receivers prologic to output 5.1?

in personal opinion - yes
2, To those who are doing this, what is preferred for 5.1? 24bit @ 48Khz or 16bit @ 96Khz? Or is there even a noticeable audible difference?
KHz depends on your media standard: 44.1KHz CDROM; 48KHz DVD-Video/-Audio, 96KHz DVD-Audio (commun knowledge is that there is no use / improovement in upsampling to 96 KHz)

finally
3, If you burn a Audio disc or DVD using BeSweet 5.1 AC3 as the audio format and then play it through a surround ound receiver what does the receiver see it as?

as Dolby Digital (when connected via coaxial/optical cabel) else scratched PCM :D

[E-Male]

Originally posted by daphy
in personal opinion - yes
could you go into some detail in how far it sounds better than dpl2?

[ursamtl]

Originally posted by Socio
I have been reading a lot of the guides and posts here and have a couple of questions regarding Stereo to 5.1 conversions.

1, It seems a lot of you go through a lot of effort and expense converting rebook CD music audio or other 2 channel music audio to DD 5.1, DTS 5.1 etc...

I know you can't actually improve the resolution of the audio on a CD. So does going through the effort to convert 2 channel audio to 5.1 and listening to it that way really sound better than just using a receivers prologic to output 5.1?

If converted 5.1 does sound better is it the converting that does it or using a different DAC output due to the conversion that give the improved sound?

I can only speak for myself in this matter. It's not about improving the resolution of the audio but in getting the listening experience as close as I can to the kind of 5.1 surround sound I hear in a well presented movie soundtrack. Dolby Pro Logic both I and II do this to a certain extent, but I've always found their results weak for my taste. This is especially so for regular stereo music recordings with no imbedded surround information. It certainly sounds nothing like the big, expansive space I hear in movie soundtracks. Through time, I came up with a system that gives me this on most material. My favorite method is using the V.I VST plugin combined with the SIR convolution plugin. I process at 32-bit, 48kHz (for 5.1 DVDs) or 44.1kHz (for 5.1 CDs), and I use impulse responses I've found for free on the net. My favorites were recorded at 24-bit at the Concertgebouw in Amsterdam. With a bit of adjustment in the balance of the impulse response and V.I's settings, I've achieved quite stunning results on a lot of material. Instruments that seem dry and one-dimensional seem to come to life but without being awash in reverb. They sometimes sound as if they're sitting in the room in front of me instead of on a recording. Pro Logic never did this for me!

2, To those who are doing this, what is preferred for 5.1? 24bit @ 48Khz or 16bit @ 96Khz? Or is there even a noticeable audible difference?The important number is the bit depth. As I mentioned above, one of my favorite impulse responses was recorded at 24 bits. The difference between 16- and 24-bit sound is noticeable, whereas the difference between 24- and 32-bit sound is not really audible. If I were just transferring the data from one 16-bit/44.1kHz to another without any processing, I'd leave it as is because you can't improve the existing data simply by converting it. However, once you start processing a file in any way, the higher the bit resolution, the more accurate the results (Creative Labs has a really effective visual presentation on their web site explaining why 24-bit audio resolution is so much better).

As for 96kHz sampling, it's far better than 48 or 44.1kHz if you're recording sound or digitizing analog material, but it won't add any sonic information to audio data already sampled at 48 or 44.1kHz. If I had an impulse response at 96kHz, I might be tempted to upsample to 96kHz for the same reasons I mentioned about bit depth, but otherwise, it's a complete waste of storage space and CPU power.


3, If you burn a Audio disc or DVD using BeSweet 5.1 AC3 as the audio format and then play it through a surround ound receiver what does the receiver see it as? As daphy answered, the receiver recognizes the data stream as being Dolby Digital provided the data goes directly to the receiver's decoder circuit without conversion to analog. This means a digital coax or optial connection is required between the DVD player and the receiver. If the DVD player first passes the audio data through a digital-to-analog converter, the digital information imbedded at the beginning of the AC3 file identifying it as such will be lost and the receiver will think it's an audio recording of digital noise!

Regards,
Steve.

[Socio]

Thanks for the info!

Sounds like it may be worth while to try and make a BeSweet 5.1 version of a CD and then do a blind test between it and the original CD with prologic.

I will however have to do some more reading on the subject; I first thought it would be as simple as take a stereo .wav and splitting it to mono then duplicating the monos for six channels, then adding a reverb to two of them for surrounds. This is not so, I see that some are using something called convolution and impulses and other tricks I have never even heard of before. There is definitely a learning curve to all this but I like a challenge so I think I will give it a go.

Thanks!