Jump to content

John Dyson

Members
  • Content Count

    777
  • Joined

  • Last visited

1 Follower

About John Dyson

  • Rank
    Junior Member

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. To me, some of the audiophile community is kind of strange when it comes to frequency response... It really doesn't make much sense (on older recordings up to about the 90's) to worry about any kind of actual frequency response accuracy -- to the ear. Of course, it is nice that average frequency responses are tolerable, but remember that a lot of the older material has 10dB of changing gain between 3k and 9k and up to 15dB of changing gain between 9k and 20k. Note that the 200Hz to 2kHz range is relatively unmolested, but 2k-3k bounces around a little, and below 150Hz also jumps a lot. * No reason for lousy frequency response in consumer equipmet , but the recordings have no sense of accuracy. When it comes to stuff like headphones and speaker -- what sounds good to you? Accuracy -- long gone in the creation of the recording for distribution. Accurate imaging and frequency response on older material (much of it, most CDs as I have finally given up to accept) are not in a pristine state at all. NR systems ARE NOT often decoded, and any idea of accuracy is nice to think about, and on pristine material is great... Alas, most pop, a lot of Jazz, and other material is not in a pristine state, and has lots of 10dB gain changes (with 30msec rates of change, or about a dB or so per 10msec, above 7-9kHz is faster.) It all flops around, along with the associated un-cancelled LF distortion... (Which is canceled upon proper handling of the recording.) John
  2. With true DIY and working for the love of the best possible results, then the discipline isn't needed, except in the 'less interesting' areas. If I was doing my project commercially, it would have been total crap, because even with the discipline, there wouldn't be enough time for all of the testing and reverse engineering. There isn't a good cost/benefit tradeoff. However, I am also a victim of 'artful design' from time to time. My project is the result of a total time commitment, but working engineers usually don't have the wherewithall or freedom to commit themselves for 100% of their life, instead they have to work 'smart'. My own project wouldn't really be very easy if planned fully ahead, where true R+D reared its ugly head also. (R+D doesn't include creating yet another preamp design, unless it has significant innovation.) The 'little-R' version of research is usually VERY hard work, most of the time an audio project doesn't entail all that much 'research'. Good results often does require GREAT commitment. Geesh, during my very boring last week, I designed the best, most wonderful audio preamp on spice -- however, we all know that the real-world result would be crap. At least, I am good enough to make a perfect temperature compensated design (transistors don't usually 'drift' all that much, they are very predictable, even being used as thermometers.) Capacitors do drift vs. temp and sometimes humidty quite a bit for example. The bottom line, that even with the detailed, accurate knowledge, being expert at 'design from scratch' -- doesn't make the work 'engineering', it is just designing. I know that YOU (Alex) know this, but just knowing the technology, even very well, doesn't make a person into a good design *engineer.* Being a good or competent designer doesn't imply that proper engineering discipline comes along with it. Even though I am very technically competent, I haven't done real electrical engineering since about 1993... Most of the time, I have adviced engineer/EE friends about more troublesome technical issues, but my advice comes without the proper engineering discipline to produce product. (Many of you reading this already know this): 'EE design' not the same as 'EE Engineering' not the same as 'EE R+D & EE R+D Engineering'. These all can come from a similar knowledge base, but the discipline and effort can be very different. John
  3. I agree with you, but the problem isn't always the competency of the EEs, but sometimtes the beancounters forcing them into weird compromises. Gotta keep good discipline!!! But generally, I agree. If cable matching, good board layout, good grounding design was moee common, then mildly substandard cables would be a little less of an issue. But then, there were (hopefully) EEs with proper engineering discipline designing the cable... It isn't just the EEs with good discipline designing one piece of equpment, but it requires reasonable EE competency of each important component, and reasonable USER level knowhow together. If some manager pushed me into a bad compromise, and I wasn't trying to feed a family, I would simply quit such a mess. Grabbing an EE college student, even one who was technically competent, and pushing them into bad positions will also sometimes result in bad design. The worst is the generally competent EE, who goes into 'design mode' without engineering discipline, producing their beautiflul art project. That kind of situation will sometimes produce bad results, but sometimes result in good stuff. I don't like artful design, just give me good i design discipline & standards, and get the help of an industrial designer for packaging. Keep the discipline with competent EE/engineers (I mean, TRUE ENGINEERS), and there will be a good chance for good results. * it is easy to forget that 'EE' who knows the technology does not necessary imply good engineering discipline and high standards. John
  4. I will happily privately share some material with people on this forum -- only after people like my 'golden ear' friend and myself don't claim too many defects. There is the important matter of not interfering with sales/etc, but people who already have the material in one form or another, some casual sharing might be nice. Sometimes, The decoding process is approximate, but we are slowly but surely making the approximation more exact. Digression, side-note: about the 'approximate' nature of decoding consumer material, and the reason why we need to test the result of the decoding effort: When the material is created, it is played from whatever tape format, and that tape recording almost always was DolbyA encoded. Then encoded DolbyA sound can be partially 'hidden' by judicious use of equalization. If they only do 'equalization', and nothing else, it can be reversed, therefore put the recording back into a normal DolbyA encoded state. The 'equalized' vs 'decoded' sound is often very inferior. There are two aspects of this 'approximate' recovery effort -- correctly choosing the corrective EQ, and correctly choosing the calibration level. The calibration level is the EASY part -- no biggie, but the corrective EQ has a LOT of variables, and in many cases there are suboptimal settings that seem nearly correct, but are in fact very much in error. The big challenge for decoding is the EQUALIZATION -- and is one reason why decoding using the very very superior DHNRDS DA decoder can still result in suboptimal results -- my choice of EQ can be in error. My hearing is easily fooled (it is variable based on numerous parameters, and I have no hearing above 14kHz, and lots of tinnitus) -- so EQ can be a major challenge. On a typical recording, there are at least 12 variables needed to make the EQ correct, but luckily most recordings have a similar EQ shape, so is not impossible. The reason for this stance (trying to be careful with the quality) is that I dont' want to 'stutter' releases to people, it just gets confusing -- and reduces enjoyment for the listener. I am happy to share some 'golden stuff' though. I am NOT the kind of person who won't share, but mass sharing can/will cause problems. So, if there is material that you are interested in, esp if you already have a digital copy with 'problems', or a vinyl copy that has 'problems', let me know. I can clean up most of those 'problems' with the decoded versions... I would NEVER charge money as I am only sharing different versions of the same recording with friends who might already have defective (undecoded/poor quality) copies (for whatever purposes.) I do not own the recordings, only my decoding software and effort, and I give my effort (and effort of those who help me test) away for free. Just send me a private message, and let me know what you might be interested in, and as we (myself and those willing to help test) create 'golden' material, we can discuss methods of transport. Money is NOT an issue, there are so many reasons why exchanging money would be wrong. The decoding software itself (which I am sure most people here aren't interested in) is a professional product (intended only for the most picky professionals), but I do give out temporary-licensed copies of the decoder gratis. (usually 2-3 month licenses, and I'll always renew.) I need to do something to keep a viable professional market for the decoder, but I don't think that most people would be interested in the decoder -- pain in the butt to use for decoding the consumer material. It is EASY for pros to use, however -- the recordings aren't all screwed up like consumer material is.
  5. There are probably some labels that did CDs correctly, I am mostly speaking of stuff like Queen, The Cars, Simon&Garfunkel, the Carpenters, and pop material like that -- when first coming out on CD. Material like Motown might be different, but I do have some Michael Jackson (was he motown during the Thriller days?) that is DolbyA... Even Sheffeild Labs CD release of 'Ive got the music in me' is DolbyA encoded. (In the case of Nena 99 Red Balloons and the Sheffeild Labs noted above, they are pure DolbyA -- really hard on the hearing.) Most 'DolbyA' material that I normally find has been EQed to be more tolerable to listen to. The hard part, and something right now that I am working with somebody on - is dealing with material that I don't know what it is supposed to sound like, and not knowing the EQ that was used... Especially with the DHNRDS, where it avoids creating distortion, it is difficult to find artifacts from mis-decoded material. (The only distortion created by the DHNRDS is when adjacent bands gains don't match where they should be, and it creates a kind of harsh, grinding distortion, almost like the ABBA sound.) John
  6. Yes, that is what I am saying. Just on random chance, a friend asked me for a decoded copy of ONJ Soul Kiss... Of course, I had to search thourgh my collection -- I found two copies... One was the original DolbyA NON-DECODED CD as originally sold (and it decodes nicely, by the way), and also one of those EVIL recent remasters, with very little dynamic range. This seems to happen on every recent sample. Note that I have found SOME CDs done correctly, but those are fewer given my selection set of purchases in the midwest USA or in my cherry picking of 'elite' non-USA copies. (That was back when I would willy-nilly spend money on recordings...) If you have an old CD, very likely it is DolbyA undecoded, a new CD is either over compressed or hyper compressed. John
  7. Sad, but probaby true... Even though there have been merits to the vinyl (digital phobic) technology, I suggest that much of the legitimacy to the digital phobic movement had been supported by the ongoing mismastering (not only lack of DolbyA decoding) of almost all of the old CDs. I have moved from the mindset that 'many' of the old CDs were poorly handled, to the FACT that 'most' of the old pop material was poorly mastered onto CD (and even today, onto other digital realms.) As I have become more and more confident of the DA decoder (here, speaking as a tool, not pushing it at all), and able to do more and more precisely accurate decodes, I am able to support the idea that the current digital presentation of the '60s through early 90's music is fairly badly corrupted. That is, it is almost impossible to reproduce the actual and expected sound of that old music. Except in the earliest days of the DA decoder, I am 100% definitely not suggesting that end users normally try to do their own DA decodes, as it 1) requires exceptional technical competence and patience -- even of this select audience, maybe a subset might be capable of RELIABILY getting good resuts*, 2) requires significant time and effort to prepare the recordings for subsequent listening, 3) distracts terribly from enjoying the music. (When I might claim that a subset of these readers might be capable, I am not including the training needed, which further diminishes the set of individuals willing to do the decodes.) I am DEFINITELY willing to help train others to use the decoder in consumer situations, but frankly *using the name in vain*, I doubt that is anyone who has the willingness or time... Even though Frank might incorrectly dismiss the significant quality advantage from time to time, he IS right about the folly of expecting end users to do their own decodes, but that IS NOT my goal here... In fact has NEVER been my goal whenever viisting this forum -- my interest is 1) the enjoyment of personal interaction, 2) inform people that they are being cheated. * If someone WANTS to know how to do the decoding that I can do, I am not standing in their way, and willing to help. I believe that it is evil, and a misery loves company attitude to dismiss the notion that someone might want a better sound, willing to do the decoding, and benefit from that. I don't naysay, and that kind of attitude is just a big downer!!!! People like you, Mr Cogley, and others who might be reading this -- we gotta help to pressure distributors and make known the travesty being perpetrated on us all. Most importantly, let them know that WE KNOW about the 'fraud' perpetrated against the customers. My goal is to create enough outrage that maybe the distributors will 1) start knowing that they are selling inferior goods, 2) once they know it, it is irresponsible to continue KNOWING that they are selling inferior product. Baby powder, for example, didn't act in the way that a normal competent consumer would expect, nor are the CDS being produced correctly.... We *somehow* need to let them know, that our quest is not for superior quality -- that isn't really needed, but instead want what is implied by CD quality. roper practices NEED to be used in mastering so that the product CAN present the 44.1k/16bit (or better) quaity that we have been paying for. I know that a lot of people might disagree with this opinion of mine -- but if I had the choice of properly mastered 320kbps mp3 and garbage/non-mastered 44.1k/16bit material, and had no way of processing the 'incomplete garbage' myself -- just give me the mp3, because it sounds MUCH better. Of course, I am personally happy that the inferior mastered material gives me a hobby, and I can produce results that are probably better than a normally mastered (by 'proper practices') CD would have been. Joh
  8. Hah!!! On Hoffman, some poor soul was complaining about the quality of one of their Roger Whittaker CD... Happily, they posted a snippet, and I responded (on the forum) with a decoded copy. These examples are 100% common -- these are REAL, SIMPLE TO RESOLVE, MASTERING ERRORS. This is a perfect example of the 'Harsh digital sound', but it does come in all forms, with all kinds of other corrective EQs. This was fairly egregious though... (The .flac is the original, the mp3 is decoded -- it is good enough to illustrate what is going on.) John River Lady Sample-decodedA.mp3 River Lady Sample.flac
  9. This a separate thread because this doesn't apply only to the DHNRDS, but the general state of the old recordings originally created/mixed down in the 1960s through early 1990's... First, the original 'Harsh digital sound' complaints didn't come from only one cause, as there were at least three reasons (not in the order of impact): 1) Early state of 'digital audio' technology. 2) Unexpected signal detail that was partially covered up by complex dynamics in vinyl production 3) Different final/production mastering for digital media vs. analog media. I believe that items 1 and 2 have been well understood all along, and the relative magnitudes of items 1 and 2 have been discussed for 30+yrs. Item 3 has been underestimated or ignored in the public/consumer arena. This is a real problem, and has varying magnitude depending on the exact difference. I dont' know enough about the final mastering (I am not speaking of mixing the material, I am writing here about the two track stereo being prepared for distribution), to know all of the steps, but there are some deviations between the handling of digital vs. analog material. --- This discussion is not solely intended to shill for the DHNRDS -- that is NOT the goal here, but maybe to explain why the 'love' for vinyl and other analog media had been sparked and even sustained for so long. There are definitely recordings which cannot sound as good as they should, some are simply NOT available in their natural form. Instead, some material is still mostly available in the 'harsh digital' form unless on vinyl or properly mastered tape. For an example of the 'natural' Carpenters sound -- refer to the link below -- it must be removed in a few days, but it is here for illustrative purposes. TRY to find a natural sounding Carpenters distribution... You might have problems doing so -- unless you have vinyl or a VERY VERY special digital copy. Even the Carpenters 'singles' on HDtracks is NOT DolbyA decoded!!! It does NOT have the natural sound. (I haven't been able to 100% accurately decode the Carpenters until recently, only possible once I found the correct inverse equalization...) I APOLOGIZE FOR THE MP3s -- believe me, they are better than any normal digital release of the same material!!!! www.dropbox.com/sh/g7bye8uii2ashq1/AACyGhV4R5FYZXDFlAz3HNFoa?dl=0 --- I have listened to a LOT of CDs made from older recordings, both CDs mastered/produced in the early days of digital, and CDs/digital produced more recently, and it is extremely clear to me that the differences can be enumerated as below: 1) No DolbyA decoding, substituted by EQ 2) No DolbyA decoding, not substituted by EQ 3) Additional manipulation, incl compression. In recent years, becoming much more prominent starting in the middle 1990s, and even more egregious in the 2000's and beyond, dynamic range has been deemphasized as a desirable trait, and loudness seems more important to the distributors. This dynamic range matter is well understood, and even some of the motivations for decreased dynamic range are understood -- it is the other items that I am writing about here. Actually, this missing step of DolbyA decoding, and the oassociated decrease in high frequency dynamic range MIGHT have been a contributing factor to the current 'loudness wars' and the consumer toleration for decreased dynamic range! --- Here is the scenario that has happened REPEATEDLY in the past: DolbyA Recording -> EQ -> distribution to consumer Instead, the following should have happened: DolbyA Recording -> DolbyA decode -> distribution to consumer One my ask: Why did this happen? I have no firsthand knowledge, but just existance proof. It has taken some time to collect the information, but there might be several causes: 1) Material already in digital form, archived by LOC (Library of Congres) procedures that make NR decoding before archiving an optional step. 2) Insufficient metadata/documentation and/or missing calibration tones making the decoding effort inconvenient. 3) Time/cost of realtime limited for HW DolbyA decoding, much slower & inconvenient than copying digial files directly. When looking at these items above, and the fact that distribution moves a commodity around, ti is not an artistic endeavor from the standpoint of the business people, I'd suspect that there is sometimes an explicit financial decision to do EQ to attempt to hide the DolbyA encoding instead of the actual decoding operation itself. EQ can be done digitally fast, while decoding actually takes 1:1 time on recording vs. time to decode. Mentioning the details of the problem again: when the mastering was done by the distributor, instead of DolbyA decoding, they did an EQ operation like this: Recording -> EQ -> distribute instead of Recording -> DolbyA decode -> distribute... So, what the remastering does is this: distribution copy -> inverse EQ -> DolbyA decode -> 'better sound results' The problem is that the original EQ isn't documented, and also the ongoing problem was that I didn't realize how precise the EQ needed to be... ---- What is my goal here -- mostly to do what I can do to resurrect the old recordings. These recordings are important to history and will NOT be heard correctly unless correctly and accurately processed.... John
  10. Here, I am announcing the 'completed' version of the ABBA decodes. In this public forum, all I can do is to provide snippets, but they are representative of the results. Most of the examples are mp3 for space saving reasons, but a few examples are .flac. There is a very significant difference in my own perception of sound quality, where mp3 seems to sound more rough... It is possible that the extreme temporal behavior of the recordings is pushing mp3 a little too hard. However, enjoy - if there is anything in particular that you already have a copy, but would like a potenially better one -- just tell me, we can make the logistical arrangements... Here are the ABBA snippets, representative of each of the ABBA albums... Carpenters are almost complete (within one iteration), but a few Carpenters albums came out substandard. I also have new Olivia and others that are either ready or close-to-it!!! https://www.dropbox.com/sh/vi7qwhk741two7b/AACjoiazLhfbY08nFADk7Ttma?dl=0 John
  11. Ah... If people are still expecting results there, I'll be happy to supply them!!! It will also help me share with a few others. This is SOOOOOO painful sometimes. It is like only 1.5dB error is a MAJOR problem... If that error is BEFORE decoding, it makes a huge difference. If that error is AFTER decoding, then it is like a bit of tone control. The mistake I made on Carpenters is 1.5dB too much below 750Hz. The EQ for material has become much more complex than what I used before. The DHNRDS is so damned accurate and clean, then fixing any minor error is actually helpful. I'll try to have the demos ready on Friday night 1November, maybe about 8pm EDT USA time. The demos will be there approx 3-5days. I will announce it on the list. John
  12. I made another mistake on 'The Carpenters'. Will be fixed by the morning. Fixing feral DolbyA is really hard to do!!! (The decoder works well, but the user -- me -- has troubles.) John
  13. OMG -- Major improvement. Basically, instead of Bug for Bug, but better MD, IMD, the new one has better drive for the stronger/intense gain variations. It pretty much eliminates the garble that exists in both the DolbyA HW and the DHNRDS DA until a few days ago. THIS IS A MAJOR MAJOR update... Give a few of the examples a listen (I made mp3s available to get a quick check, but they don't quite do the recordings justice.) The best way to describe the sound -- very pretty. I mean, VERY VERY VERY pretty!!! I haven't done the official release yet, probably tomorrow. Still might catch a last minute bug, but it is pretty damned good now. John
  14. Carpenters examples fixed (sibilance better), and ONJ coming in about 30minutes from now. John
  15. 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
×
×
  • Create New...