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1
Scientific Discussion / Re: Have a working 'expander' based on DolbyA (not same design) -- works well.
Last post by krabapple -
Your terminology is slightly confusing.  It's not surprising for a studio tape since 1965 have been Dolby A encoded; it is surprising for it not to have been decoded for commercial release .  So your concern is really 'Dolby A encoded stuff released without decoding'.

AFAIK, Dolby A decoding was not available on any consumer playback gear (e.g reel to reel decks).  So no Dolby A 2TRK tapes would have been released commercially, unless it was by mistake.  Yet you say you have  "a 2TRK copy, unprocessed and is a DolbyA master of ABBA Gold and MORE ABBA Gold."    What gives you absolute certainty that these tapes are what you say? 

Given all the adjustments to EQ and dynamic range available to CD mastering engineers, I just don't see how you can be certain that commercial releases are suffering from Dolby A nondecoding, versus normal mastering choices.   Tipped up treble is hardly rare in CD masterings, and neither is compression, and both are easily achieved without Dolby NR playing a role.

Yet you go on to claim:
Quote
Believe it or not, often the better quality disks tend to leave the DolbyA undecoded -- it is the horridly misprocessed material that isn't usefully DolbyA encoded.

I don't see how you can *know* this.

However, you also say you have 'PROVABLY' Dolby A encoded material . If that is so, then you can do the comparison I mentioned previously  (decode with a Dolby A hardware decoder vs your software).

But there's also the whole issue of the Dolby calibration tone, which would only be printed to the master tapes;  without that, setting levels for decoded playback, is guesswork....



3
Audio Hardware / Re: Subwoofer advice needed
Last post by Fairy -
I'm setting up my sub. You can even select your main speakers if they are B&W.

I found out that with Phase 0, the sub seems to cancel out the main speakers and with 180 degrees they work together.

How is this possible when the speakers are lined up perfectly next to each other?
My speakers are not out of phase, + to +, - to -.

I have exactly 30 minutes of experience with subs so bare with me :)
4
Scientific Discussion / Re: Audio Summing Algorithm
Last post by jsdyson -
If I get up the energy to play with this stuff, I can probably put together a rough 'FFT' based summer (that is, not an FFT, but power based) to see what forcing the phases to match would sound like.  I suspect the results would at least be grainy sounding (like some of the ABBA recordings due to the abuse of the quadrature/destroying the analytical nature of the signal), but more than likely renders the sound unintelligible.

Actually, I have done something similar before -- by zeroing the phase of a given FFT (magnitudes the same, phase is zeroed -- all the same), and the result was pretty much unintelligble-- it was possible to detect some of the material, but didn't seem to be useful.
Can you send us some samples, please? And why does it happen?
I have massive archives from when I played with that stuff (about 2013 or so), and will look for something to demo to you.   Like I wrote earlier, there was little benefit even with the compressor/expander thing to work in the Fourier domain (more trouble than it was worth, even though I wanted to work in multiple bands -- seems like the transform would give you lots of bands and seems like that would be good -- but it wasn't all that helpful.)  I could definitely compress the hell out of the signal, but I didn't like the sound of a 512 band compressor. :-).   It seems like 6-8bands is into the diminishing returns, and it seems helpful to try to keep the 500-2500Hz range in one band by itself -- various reasons for that.

John
5
Scientific Discussion / Re: Have a working 'expander' based on DolbyA (not same design) -- works well.
Last post by jsdyson -
Regarding my disgust as to the quality of some of the available recordings, and finding that they were like left with DolbyA encoding intact -- yes. 


So,  even though Dolby A was commonly used professionally from the mid 1960s through the rest of the analog era, either it was not noted down on many tape boxes, or the CD transfer/mastering engineers failed to notice , or simply ignored, the Dolby A indication on the tape box?

I have heard of cases of the former (Dolby used, but not indicated on the tape box) but I'd be surprised to find such cases were as widespread as you imply. 





I am truly NOT meaning to misinform, and also I know that I am not crazy (at least, probably not), but it is really interesting that I am running into a lot of DolbyA encoded stuff.

Firstly, DolbyA encoding isn't 'fatal', and some people might like the hard, over compressed HF sound.
Secondly, I was SUPER surprised, and started doubting my sanity until I got help from a recording engineer -- and have PROVABLY DolbyA encoded material.  The effect of decoding that provable DolbyA material is similar to the decoding of some popular materials.

My online demos are NOT fakes, and they are NOT contrived in any way.  Most of my stuff is now on digital media, but I still have some CDs that I can grab, decode and demonstrate the proper effects of the decoding.  I have one example on my repository that I mentioned before (and here it is again), the song is 'Bicycle', and the repo is: https://spaces.hightail.com/space/z3H68lAgmJ
(The nasty sound that I hear on Bicycle -- before cleaning up with DolbyA decoding is similar to what I hear on a lot of disks (not all of them.)  Believe it or not, often the better quality disks tend to leave the DolbyA undecoded -- it is the horridly misprocessed material that isn't usefully DolbyA encoded.

I just found my Queen CD -- it is 99.9999% determined to be DolbyA encoded: 
Queen Greatest hits:  Copyright (C) 1992 Hollywood Records, ID 61265-2,

On the other hand, I have an ABBA CD that is all compressed to hell -- I know that because I also have a 2TRK copy, unprocessed and is a DolbyA master of ABBA Gold and MORE ABBA Gold.   The all compressed to hell CD (not plausibly DolbyA encoded):
ABBA Gold, 40th Anniversary Edition, Copyright (C) 2014 Polar Music, the ID code is long and unimportant since I don't claim that it is DolbyA encoded.

YES -- there are both DolbyA and non-DolbyA recordings available on CDs and online -- but, I suspect that some percentage of the 'too much treble' or 'harsh sound' complaints from people MIGHT be because of undecoded DolbyA.

I have only made passive mention about this revelation until now -- it seems like people tend not to be interested, because THEY JUST DON"T SEEM TO BELIEVE IT.

LISTEN to the examples...  If YOU have some material that sounds DolbyA encoded (too much HF, too compressed, but not DolbyB), then send me a snippet, and I can decode and send it back.   It might be easier if you just run my DolbyA decoder on your (relatively recent) PC -- IT REALLY WORKS!!!

However, there are indeed cases where the DolbyA decoder appears to work (almost), but the material is NOT DolbyA encoded.  Likewise, very often if you try to decode non-DolbyA encoded material, it sounds like cr*p.

SO -- there are two things that should happen (for the sake of audiophile and/or simple recording quality):  people should have access to DolbyA compatible decoders, or the record distributors should spend the several hours per release to just decode the material.

One idea came to mind -- leaving DolbyA encoding on a recording is kind of a very nasty form of mastering -- it brightens up the recording and does a bit of dynamic range restriction (on the low level side.)   In this case, that is just being cheap.

Too much of my music material has been changed from harsh sounding cr*p into near audiophile quality.

John
8
3rd Party Plugins - (fb2k) / Re: Columns UI
Last post by musicmusic -
Will you implement logarithmic volume slider? Thanks
Are you referring to the fact that -10 dB isn't halfway at the moment? I can certainly fix that.

Just wondering if there's any known performance issues between CUI's spectrum analyzer and WASAPI playback. The audio is fine, but the spectrum analyser is extremely choppy when outputting to any WASAPI device. I seem to recall there being a fix for this.
I'm not aware of anything, and I didn't observe anything odd from some quick tests locally. Are any other visualisations affected? Does it happen with all tracks? What version of the WASAPI output do you have?
9
General A/V / High resolution audio - lowest audio setup?
Last post by Anakunda -
Hiyas, coz I'm quite disappointed that my audio gear otherwise can play from hires sources, but I can't make any difference of it, I'd like to have some idea where lays the perceptible threshold, and also where approximately is the true hi-res entry price level.
I realize that it may be the ears or bad mastering that prevents to hear any difference, but given that ears and record are sufficient, I'd like to have a thought how should the most minimal setup look like, which not only reads high resolution, but also is able to "write" it, ie. it can in real render the added resolution.
Can for example anybody post a sample of concrete setup where he's able to ABX 24bit PCM or DSD audio from standard resolution of the same source? (by standard I mean something like CD standard - 44100Hz/16b).
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