Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

[Saitenschwinger]

Dear dbPoweramp team und forum users,

I have one HDCD-encoded Dolby Surround CD and one Dolby Surround CD without HDCD (not SACD´s, DVD-Audio´s or similar), a very rare format. I can't find a current way to decode and convert it to a 5.1 flac (ideally as low-loss to lossless as possible). Is it possible with dBPoweramp? If yes, how and if no, any idea?

Thanks and best regards

Saitenschwinger

[Spoon]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

What do you have which can play that disc in 5.1?

[Saitenschwinger]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

Good Question, thank You. To play Oppo-BDP 93 EU Nuforce Extreme Edition Multiplayer via the ditigal output into an AV receiver with Dolby Surround decoder.

But I have a long time ago already digitized a Dolby Surround CD with the help of the computer drive to (real) 5.1-flac. But I don't know how I did it and I can't find anything about it on the web now. The last entry I could find was too long ago: https://www.kodinerds.net/index.php/...-2-DTS-CD-AC3/.

Here part 2. Is german, but can be translated with deepl.

But with this I do not succeed.

[Spoon]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

The disc does not make any sense to me, HDCD will decode in a format that is not Dolby AC3 and Dolby AC3 when decoded cannot be then decoded with HDCD.

[Saitenschwinger]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

Ah, I might have an explanation for this. These special format CDs can also be played on a normal CD player via the analog outputs. Then they behave like normal CDs. However, the surround information is encoded in the signal, which in turn can only be output for 5.1 via the digital output to an AV receiver with a corresponding surround decoder.

I would therefore assume that HDCD encoding only applies in normal CD operation and surround encoding only via the digital output for 5.1.

Under the assumption I would rephrase the question:

I have one Dolby Surround CD (not SACD's, DVD-Audio's or similar), a very rare format. I can't find a current way to decode and convert it to a 5.1 flac (ideally as low-loss to lossless as possible). Is it possible with dBPoweramp? If yes, how and if no, any idea?

I also refer again to post *3.

Thanks already.

[mville]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

These CDs (Dolby Surround Audio Discography) would need software that could first read the disc and have a Dolby Surround Pro logic decoder.

Maybe take a look at DVD Audio Extractor or DVD Audio Explorer.

[mville]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

... I'm not sure but it maybe possible to rip the CDs with CD Ripper, and then extract the discrete channels with the eac3to tool?

[schmidj]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

Aha, probably Dolby Surround or whatever they called it. An analog encoding of 4.0 surround and decoding, used extensively by the TV networks before the coming of digital TV. I think also used on analog "laser discs" or whatever they called them.

Encoder takes rear channel material and puts it "out of phase" (inverted polarity) in the encoded signal, and takes center front material and puts it in mono ("in phase") in the encoded signal.

Decoder, in Dolby surround receivers, often found in home theater setups pre-digital used a fair amount of psycho-acoustics to do a fairly effective job of making pseudo-surround over two channels.

I did audio systems design for ABC TV for 36 years, and was involved in installing many of the encoders (and decoders) in many ABC facilities. Of course it all went away with the end of analog TV broadcasting here in the USA. Digital was 5.1 discrete from day 1.

The encoded signal is pretty compatible stereo even if not decoded, two channels of audio. You could burn it to a CD, then play it back through a decoder and get 4.0 (pseudo) surround. You could certainly take the analog two channel encoded signal and run it through an HDCD encoder before burning the CD and decoding the HDCD on playback to get a little more headroom, I don't think the HDCD encoding would mess with the surround encoding, very different things.

I don't recall ever hearing of anyone using Dolby Surround to get "surround" on two channel CDs, but why not? It certainly would have worked, but then DVDs with 5.1 came along if you wanted real surround.

Personally, to me the big advantage for TV wasn't the surround, but that if you had Dolby surround decoding in your home theater with a center speaker as well as left and right, it pulled the dialog back to coming from the (in those days smallish) picture area even if you sat way off center in the viewing area. With 2.0 stereo if you sat to the left of the TV, all the sound seemed to come from the left of the TV, etc.

We ran quite a few demos of Dolby Surround before adopting it at ABC.

Look for an older A/V receiver with built in Dolby Surround decoding (I think clled pro-logic) to try listening to your CD, or the ripped audio with. The alternative is to look for one of the Dolby SDU4 professional decoders (XLR line level balanced in and out). Both show up on eBay.

[Saitenschwinger]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

Thank You All. I will give it a try and you a feedback. One thing I have already found: A Dolby Surround Decoder-PlugIn for foobar2000. I will try everything the next days.

Regards :-)

[schmidj]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

According to the Wikipedia entry, all Dolby Digital decoders include the ability to decode Dolby Surround (4.0 analog encoding into two channels) to 4 (actually 5, but the two surround channels will be identical) channels for listening. So it is quite likely that any stand alone or software based Dolby Digital decoders would include this as well.

BTW, Dolby Surround without the "pro logic" was pretty awful. The "pro logic" decoding, introduced around 1987, was much better. The "pro logic" decoding is essentially the same decoding used to get surround in theaters in the years before digital audio. So if you have old movie soundtracks or early DVDs before the advent of Dolby Digital or DTS that are in stereo, there is a good chance they are really the theatrical equivalent of Dolby Surround with pro logic, and will properly decode to 4.0 with a Dolby Digital decoder.

[mville]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

One thing I have already found: A Dolby Surround Decoder-PlugIn for foobar2000.

OK great. Try ripping the CD in CD Ripper, then play the files in foobar2000 with the Dolby decoder and see what happens.

Is the decoder you mention, foo_dsp_fsurround?

[Saitenschwinger]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

Is the decoder you mention, foo_dsp_fsurround?

Yes, ist is. I hope that this will work.

Again thanks to all

[Saitenschwinger]

Re: Rip (HDCD-)Dolby-Surround-CD to 5.1-flac?

Feedback from my side. I was able to test this out now. I ripped the CD once with HDCD and once without HDCD as wav and converted both to flac with foobar surround decoder. As expected, with the HDCD-decoded 24-bit-flacs no surround came out, but with the "normal" non HDCD-decoded 16-bit-flacs it worked, wonderful surround sound.

Thanks again to all for your help