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John Dyson

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About John Dyson

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    Audio DSP/SW developer, sometimes listener

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  1. Per-capita is higher, but the US has lots of disadvantages, including old & original infrastructure. Progress is being made monotonically though. The nearby neighbor, with less industry does have similar per-capita. The nearby neighbor has much stronger policies than the US, but not monotonic decrease. I am NOT claiming that the US is some perfect use of CO2, but instead that political command regulation itself doesn't solve the problem. The best way to do things is in an ORGANIC approach rather than command economy. I am pretty sure that if the US took t
  2. I think that I might have forgotten to announce V1.6.4A. I am working on improved docs right now, but the Using document will get you started wiith the new commands. When chatting on this forum, I had assumed that I had done the announcement... It has been in testing by a small group of people, and I simply forgot to do the announcement -- SORRY ABOUT FORGETTING! Here it is: https://www.dropbox.com/sh/1srzzih0qoi1k4l/AAAMNIQ47AzBe1TubxJutJADa?dl=0
  3. First -- the V1.6.4 series is absolutely better. We found that the EQ is most definitely based on the CD emphaiss frequencies, and not the more DolbyA natural EQ of 3kHz/9kHz. (3.18kHz/10.5kHz, 3.18kHz/18kHz, 3.18kHz/21.5kHz, 3.18kHz/forever, instead of 3kHz/9kHz, 3kHz/18kHz, 3kHz/21.5kHz and 3kHz/forever.) The very *sllght* difference of 180 Hz is like the differnece of night and day. But, if you try to run more layers, it is better to decode with a lower calibration starting point. After a lot of testing and design updates (and infinitely better accuracy), a starting point
  4. Mac does have an emulator for Windows or Linux? A port to Mac would be a significant amount of work, and I am the only programmer on the project. In fact, other than my pro project partner for DA decoding, and people who help me around here, almost everything is done by me. I dont have the resources to do it -- and I do feel regretful that I cannot do it. Some day (year or two), I will free the source, and also willing to help plug-in developers to do a DolbyA decoder or FeralA decoder (FeralA is a complex combination of DolbyA encoding and EQ.) The technology is
  5. === I really hope this helps -- learning to reliably detect/determine FA has taken me a fairly long time, and I still do make mistakes!!! === Probably a little lower DR is an indicator. FA compression is done 'inside' of a recording, so DR sometimes doesnt' change much, and then other times the difference can be profound. The confusing factor about The Cure -- FA tends to have louder 'hiss' than normal tape hiss levels. The hiss on 'The Cure' was a little stronger than usual for normal tapes. The 'woody' sound of FA is the biggest tell for me ot
  6. Right now, the decoder is VERY VERY deficient in documentation. I am spending much of my time this week producing some useful documentation, esp for beginning users. Most likely, on Fri late afternoon, there should be improved documentation, with an updated/complete exhaustive man page (converted to pdf for reading), and a better beginners guide. Also, I hope to have a more general 'user guide for success' type thing. Using the decoder now is actually reasonably easy for people who are comfortable while using Linux/Windows command lines, and a simplified version new set of options might
  7. I finally got a copy of a few selections from the Cure disk. Did some reviews... Thank you so much for finding something that I have not found in a few years of searching -- YOU WIN THE PRIZE. The Cure disk is NOT FA. The hiss on the disk is natural tape hiss, not enhanced hiss from the FA compression. I tried decoding it, even though my prejudiced opinion would be that it would fail. Indeed, all of the manifestations of expander surging. This is a good *commercial* example that I can use now -- I only have 'master tape' type material to demo non
  8. Here is a caveat -- the g, vs Gg vs G vs no-g at all, this is a slippery slope. I sugget being careful about the tradeoff between the 'body' of the vocal vs brightness vs. sibilance. Once you get the sound 'just right', but perhaps a little bit of sibilance leaks through, then consider clamping down a little on the "resonant 's'" sound. Depending on signal level, but if it is full scale, then maybe try --as=8, and see if the sibilance is SLIGHTLY suppressed, then push down a little (down as low as 4 or so) to see if the 's' is better controlled. Some recordings are done VERY WELL, a
  9. I don't have a copy of that recording, but at first -- maybe try starting with 4 layers instead of 6. Also, not using --fz will speed things up while you are tweaking the settings. Then, add --fz when you are happy (--fz doesnt' change anything, for FA, just does the gain control incrementally while filtering out the lower frequency IMD.) If you enable the full 'monty' by doing --dh=off & --fz, then it does some sideband demodulation games to clean up the sound -- but the sidebands are splattered all over the place with FA anyway, so there is sometimes only slight benefit of turning
  10. I'll check with a few people for a copy of the material, or send me a substantial piece of the selection, and I'll see what I can do with a decode. Doing only one song can sometimes be challenging though (sometimes it is a balancing act for doing optimal decoding for a given album.) The most critical thing other than no errant EQ on the direct digital download/CD, is that there be NO normalization, either on an album or selection basis. It is possible to decode an album if it is normalized all together, but normalizing on a selection basis makes life really difficult. The res
  11. The decoder is NOT fully automatic, but it is about as easy as possible in a command line. The problem is that there are MODES -- and not every recording used the same mode. There is probably a learning curve of about 1 day for someone used to command line. (BTW, they are still making NEW FA recordings -- I have a copy of Taylor Swift 'Shake it off' and Carly Rae Jepsen (Call Me Maybe) -- bog standard FA (they use rather standard, easy to select settings.) It is possible to create a simplified version (maybe not quite the quality because of the crazy math -- there are 60
  12. The decoder is right on the edge of release. The V1.6.4A is in the hands of some people who are used to using it. I am hoping to have it ready tomorrow. John
  13. Just wanted to make sure you know -- there will be final, working release soon. It will be available and forever free to use/copy or spindle/mutilate. There is quite a bit of work for cleanup and a doing a release correctly takes a day or two, probably Saturday even though the mechanics are only about 15 minutes. I believe the results are as close to perfect as can be, and given the fact that I have no specifications for the *evil* distortion scheme (on almost every digital recording sold to consumers) that I call FA. John
  14. I think that I found the EQ problem that my hearing had adapted to. I did a few more iterations and understand what went wrong. We are talking a few 10s of lines of code out of over 30k lines of very complex code. This effort (the results that I think is now working much better) has been incredibly difficult -- even after doing a decoder of DolbyA material that was claimed also to be impossible (it matches the curves perfectly.) The DA decoder was necessary as a stepping stone to do the FeralA decoding. Why do the decoding? I used to do orchestral recordings, and
  15. Major decoder bugfix coming. Don't bother with any current releases. Mea culpa.
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