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DVD-Audio extractions and multichannel to stereo mixdowns

ToTo Man

the band not the dog
I probably won't get any replies to this as it's a very niche subject, but you never know!

When I was into surround sound in the mid-2000s I bought a handful of DVD-Audio discs. I recently discovered that the DVD Audio Extractor app for Mac can extract not only the audio tracks from DVD-Video (stored in VIDEO_TS) but also the MLP-format audio track from DVD-Audio discs (stored in AUDIO_TS).

Having noticed on the dr-loudness database that Fleetwood Mac's "Say You Will" album has significantly more dynamic range when the 6-channel version on the DVD-Audio disc is mixed down to 2-channel stereo, I decided to see if I could extract it myself.

I first let DVDAE do the 6ch to 2ch mixdown. I also extracted the 6ch audio, imported it into Audacity and used it to do the 6ch to 2ch mix down. (I didn't adjust the levels of any tracks in Audacity prior to the mixdown, but the resulting mixdown was around +8dB above 0dBFS in level so, to avoid clipping, I had to lower it to below -0dBFS before exporting).

The two methods produced slightly different results. The mixdowns performed in Audacity typically has slightly more dynamic range than those done by DVDAE, around 0.75dB more on average. Not a huge difference but big enough to suggest the two programs have different mixdown approaches.

Both sound great and are a MASSIVE improvement on the brickwalled stereo release that's very fatiguing to listen to. However, given my OCD tendencies, I'm curious to know what the difference is between the two mixdown approaches, and which is the more theoretically 'correct'?

The dynamic range values DVDAE extractions match those on the dr-loudness database, but there is no mention of how the latter were obtained. The only info is a reference to it being a 5.1 DTS downmix, which is odd because there is no DTS codec on this disc?!
 
There's a guy called Robin Sharoma who downmixed all the Talking Heads 5.1 mixes to stereo and apart from the live concert downmixes, which didn't really have great surround content to start with, the downmixes of the studio albums all sound superb. They have a much better dynamic range than the official stereo mixes that accompanied their respective releases and in some cases, the downmixes are new mixes as the source material for the multichannel mixes differed from the standard stereo sources.

He made the downmixes a number of years ago now using a minidisc and PC software (Creative software/sound card or something like that) to capture the downmixed content in real-time. I got in touch with him a while ago about doing more but he said he no longer has the equipment (or the time at the time) to do so. I spent a fair bit of time after that trying to downmix multichannel content myself as I've got a lot of multichannel music but nothing I ever tried came close to the excellent results Robin achieved.

Click here to visit his website to read about the process involved and listen to the results if you haven't done so already.

ps.s, how are you getting on with the Beresford switch - is it still performing to your expectations and satisfaction?
 
Very interesting. I wonder why the 5.1 mixes are less squashed. I read an interview with mixer Bob Clearmountain in SOS recently where he stated he produces 5.1 mixes of everything he does but the audience for them is tiny.

Could it be that it's only the stereo mix that's auditioned by the label and hence subject to "more louder!" requests?
 
Anyone got a solution to burning DVD-A's?
I had Cirlinka but its reverted to trial of five DVDs. Which, as it was always a bit flakey means two or three.
I've heard you can do it on a Mac - anyone doing this successfully?
 
ps.s, how are you getting on with the Beresford switch - is it still performing to your expectations and satisfaction?

Yes, but I haven't been able to use it much as I need a second unit to complete the 'playback' leg of the chain and when I went back to order a second box I got an apologetic email from Stan informing me that he's out of stock and it might be a month until more come in, so I'm waiting patiently....
 
Anyone got a solution to burning DVD-A's?
I had Cirlinka but its reverted to trial of five DVDs. Which, as it was always a bit flakey means two or three.
I've heard you can do it on a Mac - anyone doing this successfully?
I can across a site yesterday that mentioned several Mac apps that could author DVD-A's, one of which I'm sure was Logic Pro. I'll try to find the site for you.
 
Yes, but I haven't been able to use it much as I need a second unit to complete the 'playback' leg of the chain and when I went back to order a second box I got an apologetic email from Stan informing me that he's out of stock and it might be a month until more come in, so I'm waiting patiently....

Yeah, one of my mates over in Coatbridge wants to buy one and that's what he's been told as well. How much was the switch? There's no longer a price stated for the 721 on the website - hopefully there's no price increase in the meantime.
 
Very interesting. I wonder why the 5.1 mixes are less squashed. I read an interview with mixer Bob Clearmountain in SOS recently where he stated he produces 5.1 mixes of everything he does but the audience for them is tiny.

Could it be that it's only the stereo mix that's auditioned by the label and hence subject to "more louder!" requests?

Very interestingly again, there are some multichannel mixes out there that are compressed surprisingly disappointingly LOUD, so there's still a bit of hit and miss as to whether a given multichannel mix will be more dynamic than a stereo equivalent. Sgt. Pepper's 5.1 mix? Too loud!
 
Yeah, one of my mates over in Coatbridge wants to buy one and that's what he's been told as well. How much was the switch? There's no longer a price stated for the 721 on the website - hopefully there's no price increase in the meantime.
It was £34.95 shipped, which is very good VFM compared to the supposed piece-of-sh@t I bought last year that cost me £28 shipped and has just recently seen a £4 price hike.
 
When I use DVDAE to extract the 6ch mix and then open it in Audacity, this is what I see:

51150143197_d107d70abb_b.jpg

51151604929_db0e8eb3de_b.jpg


Only the first two tracks are labelled 'Left' and 'Right' and are assigned to the left and right channels, the rest are labelled 'Mono' and play through both channels when Soloed. I cannot easily identify the LFE track, I was expecting this to be obvious and have a low pass filter applied to it, but all 6 tracks are full-range. The fourth track down, however, has the least HF content and sounds the most 'low-fi' of all the tracks so I'm assuming this must be the LFE track.

This is the resulting 2ch mixdown performed by Audacity:
51150193892_1dc5214e23_b.jpg


This is the 2ch mixdown performed by DVDAE:
51150870556_a92b3c7459_b.jpg


I've yet to critically A/B the two mixdowns to hear what the differences are in terms of stereo panning etc.

This is the hi-res stereo mix that's on the DVD-A, which appears to be fractionally more compressed than the CD release, and that was already smashed.

DVD-A hi-res stereo:
51150871856_94fbb45d11_b.jpg


CD release:
51150459747_a724cacce2_b.jpg
 
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My guess is that the channels are:

Left Front
Right Front
Centre
LFE (Sub)
Left Rear
Right Rear

It's recommended that the centre track (3) is attenuated by 3db and if you keep the LFE, that's reduced by 8db (https://www.reddit.com/r/audioengineering/comments/4phup0/how_do_i_convert_51_audio_to_stereo_while/). It looks like the DVDAE mixdown might not have attenuated the centre.

Which is better to your ears?

Looking the DR database (https://dr.loudness-war.info/album/list?artist=&album=Say+You+Will) it seems that you've identified the best sounding version: the CD has a reported DR of 6 (ave) / 9 (max) vs a DVD-A stereo downmix with a DR of 11 (ave) / 13 (max). Even the LP is pretty poor, and as for the hi-rez, forget it.
 


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