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DolbyA decoding feedback -- 'feral' examples (yes/no)


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The new versions are on the Demos and test site.  I am not 100% happy with the results, but my guess is that ABBA lovers would be hearing the most undistorted versions available.  (other releases are often 'brighter' sounding, but that bright/extra-processed kind of sound wasn't my goal.)  A relatively 'normal' vocal type sound was more my goal -- more of a full voice than  a hyped high end.    Apparently, to brighten the ABBA sound, they hollow out the LF below about 1kHz (drop it by about 1.5-3dB) which then makes the material difficult to decode, thereby producing that traditional ABBA sound when decoding the miscreant files.   Filling back in the lows then allows the DolbyA decoding process to work more sanely, thereby producing more 'normal' sound, but is also fairly non-ABBA sounding.

 

Trying to make the best, responsible decision has been difficult, and I am still not 100% comfortable.  Do I want to disappoint people who expect a 'certain' sound, do I want to get the most 'raw' material possible, or should the results be a compromise?  I probably 'compromised' too much, while still needed to do some improvement towards both general kinds of goals.

 

Important:  absolutely zero per-cut modification has been done.  All work has been done on a full album basis -- this is not an art show, but rather a 'recovery' project with a few guesses while trying to do the right thing.

 

I still think that the ABBA album (SOS & MammaMia on the Demos/examples) is still a little boxy sounding, but as you know, I am not doing 'sounds good' EQ as much as correction -- correction is a 'bug fix', EQ is making it 'sound good'.  I am trying to avoid tweaking except for 'bugfix' (e.g. messed up sibilance, very common on ABBA decodes.)  Also, they used an uncommon EQ all over the place -- making it challenging to bring the material back to baseline -- all I can do is to approximate baseline.  They did appear to have some standard EQ methods, and if they didnt -- I would have given up on this at the beginning of the attempt.

 

RingRing might be too mellow now -- (Bobby's Brother, RingRing) There appear to be two primary choices for proper decoding/raw remastering (nothing creative) of ABBA -- and I think I JUST MIGHT have made the wrong decision.

 

The Arrival album and snippets are still in process.  I intend to revisit 'ABBA' and 'RingRing' again as driven by my own dissatisfaction, but constructive feedback/criticism is welcome on ANY example.

 

The folders are in the same usual spot, and here is the snippets location (if you have any requests, I can add any snippets on request, except from the Arrival album right now -- it is still in progress.)

 

https://www.dropbox.com/sh/vi7qwhk741two7b/AACjoiazLhfbY08nFADk7Ttma?dl=0

 

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9 hours ago, John Dyson said:

The new versions are on the Demos and test site.  I am not 100% happy with the results, but my guess is that ABBA lovers would be hearing the most undistorted versions available.  (other releases are often 'brighter' sounding, but that bright/extra-processed kind of sound wasn't my goal.)  A relatively 'normal' vocal type sound was more my goal -- more of a full voice than  a hyped high end.    Apparently, to brighten the ABBA sound, they hollow out the LF below about 1kHz (drop it by about 1.5-3dB) which then makes the material difficult to decode, thereby producing that traditional ABBA sound when decoding the miscreant files.   Filling back in the lows then allows the DolbyA decoding process to work more sanely, thereby producing more 'normal' sound, but is also fairly non-ABBA sounding.

 

Trying to make the best, responsible decision has been difficult, and I am still not 100% comfortable.  Do I want to disappoint people who expect a 'certain' sound, do I want to get the most 'raw' material possible, or should the results be a compromise?  I probably 'compromised' too much, while still needed to do some improvement towards both general kinds of goals.

 

Important:  absolutely zero per-cut modification has been done.  All work has been done on a full album basis -- this is not an art show, but rather a 'recovery' project with a few guesses while trying to do the right thing.

 

I still think that the ABBA album (SOS & MammaMia on the Demos/examples) is still a little boxy sounding, but as you know, I am not doing 'sounds good' EQ as much as correction -- correction is a 'bug fix', EQ is making it 'sound good'.  I am trying to avoid tweaking except for 'bugfix' (e.g. messed up sibilance, very common on ABBA decodes.)  Also, they used an uncommon EQ all over the place -- making it challenging to bring the material back to baseline -- all I can do is to approximate baseline.  They did appear to have some standard EQ methods, and if they didnt -- I would have given up on this at the beginning of the attempt.

 

RingRing might be too mellow now -- (Bobby's Brother, RingRing) There appear to be two primary choices for proper decoding/raw remastering (nothing creative) of ABBA -- and I think I JUST MIGHT have made the wrong decision.

 

The Arrival album and snippets are still in process.  I intend to revisit 'ABBA' and 'RingRing' again as driven by my own dissatisfaction, but constructive feedback/criticism is welcome on ANY example.

 

The folders are in the same usual spot, and here is the snippets location (if you have any requests, I can add any snippets on request, except from the Arrival album right now -- it is still in progress.)

 

https://www.dropbox.com/sh/vi7qwhk741two7b/AACjoiazLhfbY08nFADk7Ttma?dl=0

 

Just got a critique that might result in a full redo -- and it *just might* be a major improvement based upon a minor adjustment. Still waiting for feedback from my correspondent, but I already have the possible improvement ready, and will replace the older versions immediately upon the feedback loop being completed :-).

 

So, might as well defer any listening/downloads until this matter is resolved.  Will notify ASAP.

 

John

 

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A few correspondents found some bugs in the sound (Chiquitita for example -- the piano and vocal meanders.)  I found that my source had been molested some how, and I found another DolbyA source with no meandering.  There were a few other bugs (minor -- originally still better than the original vinyl and CD, but improvements are always nice.)

This is not going to last forever, as I need to work on something else.  If this delay wasn't worth it, I would just have made the test and review version available already!!!

 

This WILL be worth the wait.  When/if anyone hears problems -- I am still expecting to fix the bugs.  (Remember, I am CORRECTING, not being artistic per-se.)

 

John

 

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ABBA examples updated -- on the following sites.  Feedback SUPER welcome...  I have gotten some really insightful feedback over the last week or so.  Still aint perfect, but IMO the best sounding ABBA ever.  (Wish I had real master tapes to be able to do a 100% accurate decode -- no mastering intended.)

https://www.dropbox.com/sh/vi7qwhk741two7b/AACjoiazLhfbY08nFADk7Ttma?dl=0

 

* mp3 only because of out of space (the albums elsewhere are pretty big -- taking up space)...  Mp3 on the Dropbox player can have swirls or messed up sibilance.  Higher quality available on request.

 

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14 hours ago, John Dyson said:

ABBA examples updated -- on the following sites.  Feedback SUPER welcome...  I have gotten some really insightful feedback over the last week or so.  Still aint perfect, but IMO the best sounding ABBA ever.  (Wish I had real master tapes to be able to do a 100% accurate decode -- no mastering intended.)

https://www.dropbox.com/sh/vi7qwhk741two7b/AACjoiazLhfbY08nFADk7Ttma?dl=0

 

* mp3 only because of out of space (the albums elsewhere are pretty big -- taking up space)...  Mp3 on the Dropbox player can have swirls or messed up sibilance.  Higher quality available on request.

 

 

I've been following your posts with interest and was wondering if all ABBA tracks have the Dolby-A decode problem,

 

 I have a 4 CD compilation released by Reader's Digest in Canada in 1992 called "The ABBA Collection".  Subjectively it sounds to me like someone really cared how it sounds. 

https://www.discogs.com/ABBA-The-ABBA-Collection/release/2184279

There's a discussion about the 1992 compilation on the Hoffman forum 
https://forums.stevehoffman.tv/threads/abba-the-best-sounding-albums-on-vinyl.435549/page-18

 

After reading the discussion on Hoffman and listening, I was wondering if the tracks on this particular compilation may indeed have been sourced from the original masters.  

 

I don't know if this helps without samples of the actual track, but JRiver Media Center's audio analysis gives the following results for the 1992 Reader's Digest Collection version of "Super Trouper"
Volume Level (R128) -6.9 LU
Volume Level (ReplayGain) -1.86 dB
Peak Level (R128) +0.2 dBTP; -0.1 Left; +0.2 Right
Peak Level (Sample) -0.1dB; -0.1 Left; -0.1 Right
Dynamic Range (R128) 4.4 LU
Dynamic Range 14 dB

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3 hours ago, Mayfair said:

 

I've been following your posts with interest and was wondering if all ABBA tracks have the Dolby-A decode problem,

 

 I have a 4 CD compilation released by Reader's Digest in Canada in 1992 called "The ABBA Collection".  Subjectively it sounds to me like someone really cared how it sounds. 

https://www.discogs.com/ABBA-The-ABBA-Collection/release/2184279

There's a discussion about the 1992 compilation on the Hoffman forum 
https://forums.stevehoffman.tv/threads/abba-the-best-sounding-albums-on-vinyl.435549/page-18

 

After reading the discussion on Hoffman and listening, I was wondering if the tracks on this particular compilation may indeed have been sourced from the original masters.  

 

I don't know if this helps without samples of the actual track, but JRiver Media Center's audio analysis gives the following results for the 1992 Reader's Digest Collection version of "Super Trouper"
Volume Level (R128) -6.9 LU
Volume Level (ReplayGain) -1.86 dB
Peak Level (R128) +0.2 dBTP; -0.1 Left; +0.2 Right
Peak Level (Sample) -0.1dB; -0.1 Left; -0.1 Right
Dynamic Range (R128) 4.4 LU
Dynamic Range 14 dB

 

I just looked up the 'Dynamic Range' tape on loudness-war, and compared with my Polar CD (which is close-to-original) that I do have, and a DR of approx 14dB is par-for-the-course of an EXCELLENT CD.   Of course, that doesn't actually measure the full quality (all kinds of things like proper decoding, etc.)  I am willing to listen to a 30second snippet to determine the character of your CD.  But even IF it is DolbyA encoded, as a recent private correspondent mentioned -- he likes the brighter, slightly compressed high end kind of sound.

 

  I do have a copy of the Readers Digest, 4CD release, but the 2004 version of Readers Digest. IT IS SAD -- very compressed...  THAT DOESN"T SAY THAT YOURS IS BAD.  Mine is much more recent, typical of loudness wars damage, and relegated to both the storage bin and my archives disk -- not my day-to-day usage disk.

John

 

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46 minutes ago, John Dyson said:

 

I just looked up the 'Dynamic Range' tape on loudness-war, and compared with my Polar CD (which is close-to-original) that I do have, and a DR of approx 14dB is par-for-the-course of an EXCELLENT CD.   Of course, that doesn't actually measure the full quality (all kinds of things like proper decoding, etc.)  I am willing to listen to a 30second snippet to determine the character of your CD.  But even IF it is DolbyA encoded, as a recent private correspondent mentioned -- he likes the brighter, slightly compressed high end kind of sound.

 

  I do have a copy of the Readers Digest, 4CD release, but the 2004 version of Readers Digest. IT IS SAD -- very compressed...  THAT DOESN"T SAY THAT YOURS IS BAD.  Mine is much more recent, typical of loudness wars damage, and relegated to both the storage bin and my archives disk -- not my day-to-day usage disk.

John

 

 

 

As for the "slightly compressed" comment,  for reference here are my DR measurements:

 

SONG                                CD*                       Processed

Waterloo                           12                               12

S.O.S.                                 12                               12

Mamma Mia                     14                               13

 

*20th Century Masters: The Millennium Collection: The Best of ABBA (released in 2000)

https://www.discogs.com/ABBA-The-Best-Of-ABBA/release/5421066

 

 

Thanks!

mQa is dead!

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32 minutes ago, lucretius said:

 

 

As for the "slightly compressed" comment,  for reference here are my DR measurements:

 

SONG                                CD                        Processed

Waterloo                           12                               12

S.O.S.                                 12                               12

Mamma Mia                     14                               13

 

Thanks!

The DHNRDS shouldn't much affect the 'Dynamic Range' that measures the higher level dynamics.  The DHNRDS DA decoder only has substantal effect below -20dB on the MF band, and about -10dB on the higher freq bands .  On pop material, the MF band is usually pinned at 0dB loss, and it is only the LF band (up to 74Hz/Q=1.070) and the range between 3k and 20+kHz that have any change in dynamics.  The MF band (80-3kHz) only starts pushing down the gain at very low levels (like at the quiet beginning of certain ABBA songs.)

 

Most of the signal is in the 80-3kHz band, so the 'general' dynamics are little affected even though the noise and HF dynamics are very seriously effected.  (If you watched the gain display on the DHNRDS, within very short periods the gain on the 9-20kHz band can change 15dB in a very very short interval -- much faster than the short interval in quiet spaces between syllables.)   The 3-9k range is a bit more tame.


One note, all of the fancy antiMD and anti-IMD calculations (other than some very primitive stuff) isn't done to the MF band, because it really doesn't change much and doesn't produce the 'fog'!!!


So, the difference in the decoded signal isn't so much on the peaks, but in the 'meat' of the sound.   When I measure with the SOX 'crest factor' and 'peak-RMS' ratios, usually there is a slight difference.  In the case of the SOX measurement there is usually between 0dB and maybe 1dB increase in the peak-RMS and the crest factor is also slightly modified.  Interestingly, the true DolbyA HW will increase the crest factor higher, but that higher measurment is caused by errant peaks that would be nice to clip.  The DHRNDS doesn't produce as many of those peaks in the middle of nowhere...

 

So -- the results that you get are perfectly normal!!!   But it is good to manage expectations on those measurements.

 

John

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1 hour ago, John Dyson said:

 

I just looked up the 'Dynamic Range' tape on loudness-war, and compared with my Polar CD (which is close-to-original) that I do have, and a DR of approx 14dB is par-for-the-course of an EXCELLENT CD.   Of course, that doesn't actually measure the full quality (all kinds of things like proper decoding, etc.)  I am willing to listen to a 30second snippet to determine the character of your CD.  But even IF it is DolbyA encoded, as a recent private correspondent mentioned -- he likes the brighter, slightly compressed high end kind of sound.

 

  I do have a copy of the Readers Digest, 4CD release, but the 2004 version of Readers Digest. IT IS SAD -- very compressed...  THAT DOESN"T SAY THAT YOURS IS BAD.  Mine is much more recent, typical of loudness wars damage, and relegated to both the storage bin and my archives disk -- not my day-to-day usage disk.

John

 

Thanks for the response.  If there's any added compression to the 1992 4CD mastering, I sure can't hear it.  The tracks sound "depthy", not at all compressed or "bright", at least to me, and are by far the best versions I've heard on CD.  They sound "right".

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21 minutes ago, John Dyson said:

The DHNRDS shouldn't much affect the 'Dynamic Range' that measures the higher level dynamics.  The DHNRDS DA decoder only has substantal effect below -20dB on the MF band, and about -10dB on the higher freq bands .  On pop material, the MF band is usually pinned at 0dB loss, and it is only the LF band (up to 74Hz/Q=1.070) and the range between 3k and 20+kHz that have any change in dynamics.  The MF band (80-3kHz) only starts pushing down the gain at very low levels (like at the quiet beginning of certain ABBA songs.)

 

Most of the signal is in the 80-3kHz band, so the 'general' dynamics are little affected even though the noise and HF dynamics are very seriously effected.  (If you watched the gain display on the DHNRDS, within very short periods the gain on the 9-20kHz band can change 15dB in a very very short interval -- much faster than the short interval in quiet spaces between syllables.)   The 3-9k range is a bit more tame.


One note, all of the fancy antiMD and anti-IMD calculations (other than some very primitive stuff) isn't done to the MF band, because it really doesn't change much and doesn't produce the 'fog'!!!


So, the difference in the decoded signal isn't so much on the peaks, but in the 'meat' of the sound.   When I measure with the SOX 'crest factor' and 'peak-RMS' ratios, usually there is a slight difference.  In the case of the SOX measurement there is usually between 0dB and maybe 1dB increase in the peak-RMS and the crest factor is also slightly modified.  Interestingly, the true DolbyA HW will increase the crest factor higher, but that higher measurment is caused by errant peaks that would be nice to clip.  The DHRNDS doesn't produce as many of those peaks in the middle of nowhere...

 

So -- the results that you get are perfectly normal!!!   But it is good to manage expectations on those measurements.

 

John

 

 

The graph below is for 'Waterloo'.  The blue is for my CD. The white is the processed version.

 

 

image.thumb.jpeg.14fd8982e327e8e0ab01abfd4f6f00db.jpeg

 

 

The largest frequency drop-off (for the processed file) appears between 7 and 20kHz.  Is this to be expected?

 

 

 

 

mQa is dead!

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9 minutes ago, Mayfair said:

Thanks for the response.  If there's any added compression to the 1992 4CD mastering, I sure can't hear it.  The tracks sound "depthy", not at all compressed or "bright", at least to me, and are by far the best versions I've heard on CD.  They sound "right".

It is great if your material is good.  Good ABBA material happens so very seldom.  That is one reason why I am trying to clean up to be very close to the signal BEFORE DolbyA even touched it...   How important is such an improvement when starting at the level of your CD? -- the DHNRDS improvement is probably not all that big of a deal.  If starting with most of the disks sold as new today (I mean, the commodity ones -- the worst is 'The Complete Studio Recordings, for example), then either mine or the version that you have would be a significant improvement.


Frankly, one of the reasons why I am doing it:  do you know the saying -- because it is there?   This thing IS like climbing a mountain.  If I had the master tapes, the quality would be amazing -  as it is, I have to reverse engineer the manipulation on the recordings, which is perhpas 10X as complicated and time consuming as just decoding something like a master tape.

 

No matter what -- ENJOY!!!

 

John

 

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1 minute ago, lucretius said:

 

 

The graph below is for 'Waterloo'.  The blue is for my CD. The white is the processed version.

 

 

image.thumb.jpeg.14fd8982e327e8e0ab01abfd4f6f00db.jpeg

 

 

The largest frequency drop-off (for the processed file) appears between 7 and 20kHz.  Is this to be expected?

 

 

 

 

Yes, definitely normal.  Up to 10dB into the 9kHz range, and 15dB above that.

 

John

 

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1 minute ago, John Dyson said:

Yes, definitely normal.  Up to 10dB into the 9kHz range, and 15dB above that.

 

John

 

I do want to explain something though.  If you had a 0dB signal at 15kHz, you'd see close to a 0dB loss.  But as the signal level drops (starting at -- maybe approx -10dB, then you'll loose 2dB or so for every 1dB loss.)   Since HF is ON AVERAGE at a lower level, it will look like there is a big drop at higher frequencies.  However, for quick transients above -30dB or so at HF, then the signal will increase in level faster, to where once the transient signal hits somehwere between -10 and 0dB, then you should have 0dB loss.

 

So, the AVERAGE loss is to be expected -- that is part of how the NR works.  However, on peaks or louder signals, then the signal is more passed through with relatively less molestation.

 

John

 

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6 hours ago, Mayfair said:

 

I've been following your posts with interest and was wondering if all ABBA tracks have the Dolby-A decode problem,

 

 I have a 4 CD compilation released by Reader's Digest in Canada in 1992 called "The ABBA Collection".  Subjectively it sounds to me like someone really cared how it sounds. 

https://www.discogs.com/ABBA-The-ABBA-Collection/release/2184279

There's a discussion about the 1992 compilation on the Hoffman forum 
https://forums.stevehoffman.tv/threads/abba-the-best-sounding-albums-on-vinyl.435549/page-18

 

After reading the discussion on Hoffman and listening, I was wondering if the tracks on this particular compilation may indeed have been sourced from the original masters.  

 

I don't know if this helps without samples of the actual track, but JRiver Media Center's audio analysis gives the following results for the 1992 Reader's Digest Collection version of "Super Trouper"
Volume Level (R128) -6.9 LU
Volume Level (ReplayGain) -1.86 dB
Peak Level (R128) +0.2 dBTP; -0.1 Left; +0.2 Right
Peak Level (Sample) -0.1dB; -0.1 Left; -0.1 Right
Dynamic Range (R128) 4.4 LU
Dynamic Range 14 dB

 

See http://dr.loudness-war.info/album/list?artist=ABBA&album=The+ABBA+Collection

 

Seems normal except Waterloo (the song) and S.O.S. seem slightly compressed.

mQa is dead!

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I was comparing my polydor CD with the DHNRDS DA decoded version...  Interesting results.   DHNRDS shows significantly less noise in the spectogram.  I am wondering what the mechanism is.  I do know that the DHNRDS does remove more noise than a DolbyA.  I am wondering if it is the ability to process almost theoretically infinitely fast(not hindered by modulation effects slowing things down in odd ways.)  I have noticed better NR on master tapes also.   The top versions are the DHNRDS, and made sure levels matched.

 

John

Screenshot from 2019-09-24 16-26-10.png

Screenshot from 2019-09-24 16-33-44.png

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1 hour ago, John Dyson said:

"...No matter what -- ENJOY!!!"

 

Thanks - that's what it's all about!  I think the labels have done and are doing posterity an even greater disservice in leaving us a legacy of compressed music.  It's a travesty to turn Dire Strait's Brothers in Arms from audiophile to garbage pile with compression - but you can still buy the original 1985 audiophile version on CD in the used market.  But for contemporary artists like Amy Winehouse, there is no audiophile version.  We and she and those not born yet deserve better.

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7 minutes ago, Mayfair said:

 

Thanks - that's what it's all about!  I think the labels have done and are doing posterity an even greater disservice in leaving us a legacy of compressed music.  It's a travesty to turn Dire Strait's Brothers in Arms from audiophile to garbage pile with compression - but you can still buy the original 1985 audiophile version on CD in the used market.  But for contemporary artists like Amy Winehouse, there is no audiophile version.  We and she and those not born yet deserve better.

So frustrating -- I just pulled out my copy of Dire Straits -- Money for Nothing...   Lo and behold -- a nice, clean recording...  No DolbyA distortion so common on music of that genre.

 

I work on a DolbyA decoder (the most effective one possible) because I hate the distortion from the NR encoding/decoding/processing/etc.   The only way to really recover many of the old recordings is to do a complete and proper (I mean do EVERYTHING POSSIBLE) to get back  the original signal as closely as possible.

 

This 'Dire Straits' thing is fantastically clean -- the way that it SHOULD be!!!  Imagine, that is ancient technology -- nowadays relative perfection is really possible.

 

John

 

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23 minutes ago, John Dyson said:

 

This 'Dire Straits' thing is fantastically clean -- the way that it SHOULD be!!!  Imagine, that is ancient technology -- nowadays relative perfection is really possible.

 

 

Oh, yes  - "Money for Nothing" -  18 dB DR in 1985;  7 dB DR in 2005 20th Anniversary Edition.  Seems to me akin to remastering the Sistine Chapel in DayGlo.  Relative perfection appears to be matter of willingness, not ability.  New releases in classical music and to a much lesser extent jazz  (where creeping loudness has crept in) show off what recording technology can achieve when both the willingness and ability are there to use it. IMHO.

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39 minutes ago, Mayfair said:

Oh, yes  - "Money for Nothing" -  18 dB DR in 1985;  7 dB DR in 2005 20th Anniversary Edition.  Seems to me akin to remastering the Sistine Chapel in DayGlo.  Relative perfection appears to be matter of willingness, not ability.  New releases in classical music and to a much lesser extent jazz  (where creeping loudness has crept in) show off what recording technology can achieve when both the willingness and ability are there to use it. IMHO.

 

The 2013 MFSL SACD isn't too bad:

http://dr.loudness-war.info/album/view/127394

mQa is dead!

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On 9/16/2019 at 12:55 PM, John Dyson said:

The designers of your equipment have to toil very intensively and with great effort to produce those unicorns.  Even MIT/Stanford graduate PHds have problems with some of those techniques.  Often, the highly advanced institutes in Haiti have to be called upon to do the level of design that supports manifestation of unicorns.  I *have* heard that there are some institutes in the southwest US have special resources that they call on that encourage the manifestation of unicorns and other associated sensory experiences.  The gov't seems to frown on such advanced technology, but the leading edge has never been simple to deal with.

 

For my own very settled down lifestyle, I prefer the more mundane -- because  my days of recreational 'listening' are long long gone... :-).

 

John

 

 

Not the SW - it is the Chinese that are going full bore with gene clipping.  Your unicorns will speak Mandarin... or maybe Shanghaiese

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WRT the ABBA 'decodes' and 'preparation' -- I found a better way of compensating for the EQ done during previous fake-mastering of the feral material.  It is necessary in the recovery effort to boost the 3kHz range by 6dB for it to match what DolbyA likes, but my estimations have gone through several generations of improvement.   The newest version (just figured out this morning) does all of the needed EQ, follows all of the rules (common sense and otherwise), but mitigates the 'hitch' in the sibilance so often found on, for example 'SOS'.  So, ABBA and several others that are sensitive to the difference in using the new filter layout (A single Q of approx 0.793 instead of two filters with a Q=1.0 and Q=0.707 that balance out the response.)  Apparently, this new arrangment does fix a long standing problem in a lot of ABBA remasters, and will show another improvement.

This 'fix' will allow me to bring the brightness in SOS up to the normal releases without allowing the 'hitch' in the sound through.  It was this 'hitch' that forced me to avoid the additional treble boost to create the sound found so often on some (most) of the commonly available release.   Don't get me wrong -- it really does appear that the super-bright sound of the sibilance is probably not on the original recording, but appears to be a mastering choice.  I am NOT doing mastering, but more of a recovery effort.  However, I am also going to heed the suggestions to sound more like the releases when it makes sense.

I'd suspect that the redecoding and checking of the new results will take another day.  Sorry about these delays, but this work DOES result in improvements.

 

John

 

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  • 1 month later...

Good news -- major upgrade to beyond a bug-for-bug, but better emulation of DolbyA.  I have removed the 'bug-for-bug' on some of the behaviors (due to certain kinds of drive limits.)  By removing those limits, the sound quality has become astonishingly better yet.  Refer to this as posted on another forum:

 

 

-----------------------------------------------------

 

Gang -- the new version of the DHNRDS (actually, I haven't officially produced a release yet, will do so tomorrow) is still working very well :-).
PLEASE ENJOY, and feel free to criticize (kindly :-)).
 
I'd suspect that most people reading this already know the context of the DHNRDS DA decoder, basically intended to resurrect older recordings, eliminating the DolbyA HW as a quality limitation.   Note that the DolbyA HW isn't all that bad for mixing down, because the material being mixed tends to have relatively simpler dynamics and signal statistics.  The DolbyA doesn't do too bad for mixing down, but could be improved on.  Where the DolbyA really falls down is handling the final mix.  All of the interactions in the individual signals added together are too much of a challenge for DolbyA HW.  (Lets keep in mind, the DolbyA was designed in the middle 1960s, and Ray Dolby was pretty much a magician designing the DolbyA itself.)   The DolbyA design has definite indications of genius in the circuitry -- it is MUCH MUCH more intricate than an initial read of the schematic might suggest!!!
 
* Most of my decoding is done on the brighter side...  It can be toned down, but choosing the correct EQ is tricky as hell!!!  Also, the recordings could stand a little better balance -- again I chose a brighter decoding result, but can be tamed.
 
I unleashed the DHNRDS DA from being 'Bug for Bug' compatible with the DolbyA, and basically changed it to be 'as good as possible'.  The sound might be VERY different than you expect, esp for ABBA. LindaR should seem REALLY good also. Of course, my taste might not be quite right.   My own initial opinion is 'astonishing' sound quality.

Mega Caveat: IS very tricky to undo the EQ that was done to skip the DolbyA decoding step -- I can provide the parameters that I used, and you can try passing the material through a true DolbyA if you wish -- given the parameters that I provide. I doubt that you would like the sound of the DolbyA in comparsion, but each of us has our own opinions. :-).  Normal professional use of the DHNRDS does NOT need for the EQ correction, but decoding feral DolbyA is a very tricky thing to do!!!

Please be tolerant of me about the Carpenters recordings. You might notice more sibilance than normally desired. I think that part of the issue is that the true DolbyA cannot track the signal, so it was enhanced to compensate. Since the DHNRDS DA can track ANY audio signal, the boosted sibilance is passed through cleanly. If mastering the Carpenters material, it might be a good thing to run it through a sibilance processor or maybe change the pre-decoding EQ a little on the most egregious songs. Usually a little bit of manipulation in the 6kHz range can help, but the pre-decoding EQ is totally vanilla and is intended to be correct, not just to sound good!!!

I have produced some snippets (full recordings on request) of some stuff that has probably not been heard as cleanly for at least 30yrs. So far, there are some 'Linda Ronstadt' recordings, and some 'ABBA'. Carpenters is coming in another hour or so, and also I plan to produce some Olivia Newton John snippets.

The Linda Ronstadt examples are NOT 'manipulated' after decoding, and I don't plan any manipulation of ONJ or Carpenters either. (More will likely be coming, e.g. Bread -- which REALLY sounds good now.) The ABBA stuff has been slightly manipulated after decoding because their tonal balance is too biased away from the bass range, so I have added about 1.5dB below 360Hz on ABBA for easier casual listening.

Of course, LindaR and ABBA are done, and I have the correct decoding parameters for Carpenters and running the decode just this second.
 
I'd suggest checking the repository now (or whenever) and looking again every day or so for new stuff.
 
 
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Mega -- important comment about these demos...   Even though I supplied MP3 versions for convenient listening, the flac versions are really needed for the correct clarity/impact.  I am not someone who will make claims like mp3 is inferior, but mp3 really IS inferior relative to the extreme quality of these demos!!!

 

John

 

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