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

[John Dyson]

2 minutes ago, fas42 said:

 

The CD I have is of the '75 album, from Discogs,

 

ABBA ‎(CD, Album, RE),

Polydor,

831 596-2,

UK & Europe,

1987

If you could run 'sox stats' on the Ring Ring cut (or any of them) we can compare to see if it is equivalent to any of my CDs.  You might actually have a better one than I do.   I think that  I have the best one available, but I could be wrong...

 

Maybe send the first 1 minute of the Ring Ring cut, and I can compare.  If you have a better one, I might try to get a copy.

 

John

 

[John Dyson]

1 minute ago, fas42 said:

 

Which is a shame. Having a full set of files to check things over will make it easier to understand where the winning and losing is occurring ...

Comparing Dolby equivalent units isn't important to me for the ABBA project.  No matter what, if the decoder 'decodes' reasonably well, it is better than not decoding at all (well, Satin doesn't make any difference -- it really doesn't sound right as a decoder.)

 

I am trying to make ABBA sound better -- the same formula can be used for ANY decoder, I'll make the mastering steps available, so if someone wants to 'waste' the time and try other units, then they can do it :-).

 

John

 

[John Dyson]

9 minutes ago, sandyk said:

 The point here, was that this is a genuine Swedish CD  from the 1973 recording .

 There is no guarantee that yours isn't a remastered copy, or that it even sounds the same as the genuine Swedish release !

Polydor and Polar are usually very similar. I have often noticed that the best quality releases are from Japan believe it or not!!!  Weird, huh?  SO, if there is a European and Japanese Polydor, the Japanese version usually technically has fewer flaws, and the European Polydor vs Polar are often (not always) the same (exactly -- within 0.01dB literally.)

 

Discomate and others are also often very good.  I might even be using a Japan Discomate for one of my source albums.  I check the stats on the CDs very, mega carefully!!!   I don't think that I am using Atlantic or any of those right now -- I am not religious to the brand.  Also not using any of those 'remastering' brands  -- they sometimes seem to have huge generation loss.  I do use some of the off-brands for an alternative reference, and my first recognition of DolbyA material was an ABBA Gold CD (1992, Japan.)

 

Of course, no matter what, I do listen to the CD also to make sure that the stats didn't show the whole truth.   I have some source material with tape dropouts also.

 

Esp for ABBA and the variability of the releases -- it can be tedious to find the best material.

 

John

[John Dyson]

47 minutes ago, fas42 said:

 

The CD I have is of the '75 album, from Discogs,

 

ABBA ‎(CD, Album, RE),

Polydor,

831 596-2,

UK & Europe,

1987

Below, I am NOT criticizing your disk AT ALL, rather trying to explain the DolbyA decoding problesm with material which might come from different albums. 

 

I just checked -- the Ring Ring on that ABBA disk is not on the original album.  For decoding,  is critical that the levels be correct.  It is more likely that the levels are correct on the original albums.  Mastering is often done on an albumb basis like what I am doing -- but splitting the cuts might/might not cause inconsistencies.  That is -- if the distributor normalizes the songs on the disk, then I cannot decode it nearly as easily.  It is a royal pain in the butt to find the correct calibration levels, and bad enough to do it once for an entire album.  It is downright evil-tedious to have to find the calibration for each cut individually!!!  (When doing an entire album, one can cross check different cuts for errors -- when doing songs individually, it is so very easy to make mistakes -- I make mistakes ALL of the time when entering things like gains and calibration levels.)

 

On those 'combo' disks, the material might be normalzied, might not be normalized, or the source might just be copied form the source of another album with a different calibration level.

 

When doing a DolbyA decode, it is better to do it on an album basis (as an entire album), or make sure that all of your files come from the same album and have exactly the same calibration.   When they have normalized each song, that means that the DolbyA decode must be recalibrated for EACH SONG instead of on an album basis.

 

On top of that (which would be beneficial for you) -- the CD might actually be properly decoded!?!?  I don't know!!!  The ideal state is if a disk has actually been properly mastered...

 

John

 

[John Dyson]

9 hours ago, sandyk said:

 

That sounds like undecoded Dolby A to me !

 The original POLCD -242 version is way more balanced sounding.

Yes -- it (RingRing.30s.wav) sounds like DolbyA that has been EQed to be listenable.

I cannot judge how people other than myself perceive the sound, so I cannot/will NOT take away other peoples (incl Frank's) enjoyment.  Compressed/EQed DolbyA does have a certain character that one can get used to and enjoy, but my project isn't to replicate what is commonly available.

 

The sad thing (for me) is that I am so tired of their wonderful music, but still must complete the (hopefully collaborative)  effort of all 8 albums (I misttated 7 albums before -- I forgot to decode one album, and only counted those that I had processed/remastered in my current working area.)

 

The RingRing album demo is complete/ready convert to a final demo format (starts with 96k/24, then I convert to mp3, flac, opus or whatever the most reasonable demo format currently is.)  Since Frank provided .wav, I also produced a 16bit/44.1k wav (if that is what people like around here -- I am happy to do it!!!)   This is a version that I have ready for review, but haven't posted it (which will be the complete RingRing album -- in snippet or full form, depending on the situation.)

 

I have included a snippet from both the 'remastered' version and also rip from original vinyl done at 96k/24 converted to 44.1k/16.  I have another vinyl rip of lower quality with very similar general sound characteristics of the higher quality vinyl rip.   I normally like to provide 55secs, but I truncated shorter because the size is adequate....   An EQed DolbyA copy has already been posted.

 

 

01. ABBA - Ring Ring.wav 01. ABBA - Ring Ring-vinylrip.wav

[John Dyson]

I have mentioned 'DolbyA fog' in the past.  When doing the 2nd pass (actually first pass done right) Arrival album, I found a pretty obvious case of DolbyA fog.   Even though I probably used different parameters for the mastering (actually turned out moderately close to the vinyl) -- there is a difference, between the two, in sound that goes beyond EQ.

 

I have provided two examples, one from the original vinyl, which I used 'DolbyA' in the filename.  The other is from the best DolbyA encoded CD that I could find, but used the DHNRDS DA to do the conversion from the DolbyA form to the natural form.  I added 'DHNRDS' to the the name of the DHNRDS DA decoded version.

 

When doing the reference comparison -- making sure that the mastering attempt isn't too far in error, I found a pretty obvious case of DolbyA fog, and shows the primary difference in sound between a true DolbyA and the DHNRDS in the high quality mode.  In the lower quality modes, the DHNRDS can produce a slight amount of fog -- if needed. On much, less-ABBA-like material, the DHNRDS and DolbyA sound close to identical, except for a bit more precision/clarity -- not enough to complain OR advertise the difference.

 

What to listen for on the fog?  there are two primary aspects of fog on this example 1) choral vocals 'smooth out' into a tonal average instead of maintaining as much individuality 2) there is left-over compression in the DolbyA version.  This left-over compression-like sound is caused by similar mechanisms as the 'choral' tonal average fog.

 

The 'fog' doesn't always sound bad, even though it sometimes does sound bad -- because other kinds of distortion can be associated & generated by it.  In a way, the 'fog' produces a 'ghosty' veil kind of sound -- which can be a valid sound-effect, but it isn't accurate.  The DHNRDS has both the advantage and disadvantage of being very, tediously, extremely accurate.  Sometimes a little original DolbyA soft-focus is a good thing, but DolbyA wasn't mostly intended as a sound effect.

 

John

 

01-When I Kissed The Teacher-DolbyA.wav 01-When I Kissed The Teacher-DHNRDS.wav

[John Dyson]

Many of the latest decoding attempts are now uploaded to the Dropbox sites.   There is a full review version for Arrival&RingRing on the test site.  The 'quick review' site has fairly long snippets, unfortunately the snippets are mostly mp3 -- but if there are problems with mp3, just avoid the Dropbox player.

 

I actually tried a first cut of remastering  'Arrival', which has some eccentricities that makes processing difficult to do correctly.  It isn't so much 'EQ' as it is dealing with that rubbing grain in 'Dancing Queen'.   The Dancing Queen mp3 review copy is SO BAD when playing through the dropbox mp3 player, it really needs to be downloaded to listen to (it swirls all over the place on the Dropbox player.)  I think that a FLAC snippet version for Dancing Queen will also be uploaded the review site in a few minutes.  MP3 is slightly challenged by the Dancing Queen 'rubbing' sound.

 

The test (alternative) site provides more precision for those might actively help -- and so it is always 16bit flac -- I finally given up on mp3 for the serious collaborative criticism and review.  I am keeping mp3 for the cursory review site because it is so very easy to play the examples through the dropbox player (sometimes with some loss of precision.)

 

There has been NO 'creative' enhancement to the remastering copies, only decoding and the needed EQ to bring the signal to DolbyA specs, and a minor correction sometimes needed for DolbyA decodes.  There is ZERO artistic modification, serious equalization, anything like that.   Any 'artistic' changes will result only from those who comment and tell me what to change (or even people who might want to directly collaborate on the project.)   My listening skill is more tuned to finding errors rather than trying to make things 'sound good'.  Anything that I try to change to 'sound good' usually ends up 'sounding bad' to everyone else, so I avoid doing it.

 

Probably the biggest difference in sound between the vinyl originals and the remastering attempts -- other than the actual mastering done on the vinyl copies -- is that the DHNRDS enables significantly more transparent detail, when the detail exists.  (There is almost zero 'soft focus' in a DHNRDS decoding at high quality levels.)  The vinyl copies have much more mastering/modification than the DHNRDS versions.  I have tried to keep the decodes/mastering VERY 'vanilla' with minimal changes to produce technical correctness only.

 

Constructive criticism where I can act on the changes are greatly appreciated, and a credits log will be maintained.  It would not imply endorsement, but only an attempt at thanks - and will be included in any proper commercial releases if they ever happen.  (Sometimes, my hobbies turn into something important, and I almost always collaborate with others --almost always  participating a collective effort with mutual respect and acknowledgement.)

 

(The Dropbox locations have already been shared, but I'll provide the locations upon request.)

 

On the ''Pink Panther':  The latest 'Pink Panther' is the best that has been decoded so far, it is ONLY a decode, so the only possible changes are for the calibration level or corrective EQ on the input (converting the EQed listenable version to proper DolbyA frequency response.)  The only likely needed tweak -- as it is on almost any high quality DolbyA decode EVEN ON DolbyA HW, is a modification of the calibration level.

 

John

 

 

 

[John Dyson]

13 minutes ago, kumakuma said:

 

Unfortunately, I'm still waiting for unicorns to magically appear in the sweet spot between them.

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

 

[John Dyson]

A first cut remaster of the 'SuperTrouper' album is done for the test site, and I'll upload the snippet examples to the quick review site in a few hours.   The SuperTrouper results are pretty good -- esp considering the IMD and MD prone 'SuperTrouper' song.   I had to do something cringeworthy -- making me very uncomfortable that I had to do a little EQ.  I am still trying to find some way to work around the need to do any serious EQ.   I have been restricting changes to adaptations for DolbyA decoding and temporal corrections - SuperTrouper really needed work.

However, I fully expect criticism on the SuperTrouper album -- maybe just for the abstract reason that I did do some EQ that I tried to commit to avoid.   I did nothing drastic -- not like 'treble boost' but  3dB boost/cut from 5kHz to 8.5kHz or so.  I don't like peaky or resonant type parameteric corrections unless there is an overriding reason, so it is just a modification to produce a bit more presence.  I might find a a solution to that -- IMO -- HACK -- later on.

The SuperTrouper snippet examples like 'SuperTrouper', and a few other interesting songs will be on the 'quick review' site later on (probably in 2-3Hrs.)

 

John

 

[John Dyson]

I posted something that I  shouldn't have ...  Had to delete!!! :-).

[John Dyson]

Status update -- I just did a reset, and will provide new examples on the review/demo site (and the full material set on the test site) just before 12 midnight USA EST on 20Sep.  I figure that I learned a few things, and rather than people waste their time reviewing some mistakes, I'll provide MUCH better material.   BTW -- I got a super clean/smooth SuperTrouper!!!   It is still 'SuperTrouper', and a little flawed, but much better than I have ever heard before.   By far, most of the results have at least 18dB peak-RMS (much in the 19-20 or more arena) and the crest factor is seldom less than 7.5!!! (mostly in the 9-10 range.)   These recordings are VERY clean and not very compressed over and above the original recordings.

I hope to have the material for 5 albums ready (snippets on the review/demo site.)

 

With some friends, we all might be able to make those proverbial 'ears' into a nice, silk purse :-).   The original recordings are great, it is just something was lost in the preparation for vinyl & CD...

 

John

 

[John Dyson]

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

 

[John Dyson]

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

 

[John Dyson]

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

 

[John Dyson]

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.

 

[John Dyson]

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

 

[John Dyson]

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

[John Dyson]

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

 

[John Dyson]

1 minute ago, lucretius said:

 

 

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

 

 

 

 

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

 

[John Dyson]

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

 

[John Dyson]

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

[John Dyson]

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

 

[John Dyson]

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

 

[John Dyson]

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:

 

 

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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.

 

www.dropbox.com/sh/g7bye8uii2ashq1/AACyGhV4R5FYZXDFlAz3HNFoa?dl=0

 

[John Dyson]

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