Post by jsdyson on Aug 31, 2018 11:55:09 GMT
Some people might know that I use ABBA for one of my tests cases on an important project that I am working on. However, this is more about ABBA than my project.
Since I use the ABBA material for tests, I have become somewhat technically familiar with the quality of various versions of the ABBA distributions, and some have been very disappointing. The best ones are the least accessible to the normal listener today -- both the vinyl versions and the DolbyA encoded CDs (including the 1992 ABBA Gold CD -- it IS DolbyA encoded, at least the one that I have.) And, of course vinyl isn't very available to most people any more. (You CAN get the DolbyA encoded versions relatively easily -- but decoding them is where the accessability is impeded.)
Before someone thinks -- oh, but my favorite copy, thus and thus is good -- well, nothing that I have found (including a few Polar/Polydor releases, and also the ABBA 'the complete studio recordings) are as good as the old vinyl distributions (the vinyl itself might be damaged, but the quality of the recording is pretty good) or properly decoded DolbyA encoded versions.
First, there is some kind of damage done to the masters that seems to have occurred since the early vinyl releases. Some of this damage can be undone, but is a rather extreme technical measure for most people. I explain in the paragraph at the end, which you can ignore if you want. This damage is IN ADDITION TO the frustrating DolbyA encoding.
The digital Polar/Polydor (not all are the same, but I am speaking in generalities right now) apparently were not DolbyA decoded very well, but seemed to come from a reasonably good master tape. In one or two cases -- e.g. one of hte Polar Supertrouper copies -- was done significantly better than a lot of US domestic versions.
The most potentially beautiful copy, but also the most atrociously over processed version is the 'The Complete Studio Recordings'. If they hadn't overcompressed it so severely, it would have been better than any other copy that I have. The crest factors and the peak-average ratios are atrociously small, and indicate a very good quality and too aggressive compressor being used :-). The recordings are 'pretty', but have lost some of the good parts of the ABBA sound. I have tried 'uncompressing' the TCSR recordings -- with some success, but could never regain the proper crest factors and peak-average ratio (I call it 'uncompressing' instead of 'expanding', because the goal is to undo an effect, not to add a new one.)
Except for the vinyl, and superficially pretty bad quality -- the releases like ABBA Gold 1992 are actually the best, if you can DolbyA decode them. Unfortunately, ABBA & DolbyA are not very nice friends -- ABBA is incredibly tricky for DolbyA to decode because of the mixed high pitched voices, and otherwise intense HF sound. That creates huge amounts of intermodulation, and is one reason for many ABBA releases sounding too compressed during 'crescendos' in their singing. My DolbyA compatible (not licensed or encouraged by Dolby labs) decoder DOES do a fairly good job of undoing the DolbyA encoding (much better than DolbyA HW), but still it would be much nicer to have clean copies of the pre-encoded master tapes to work with. (The compression effect when encoding/decoding difficult material for DolbyA seems similar to mild overload of tape itself... Such intermodulation effects do sometimes cause a sound that is similar to gain compression.)
So many of the ABBA releases have been needlessly damaged, and after the some 5-10copies of each song/recording that I have (probably more than that number), it is so sad to hear all of the major differences in the releases, yet KNOWING that it sounded much prettier in the studio. The saddest thing (but potentially most fortunate in the longer term) is that so much pop music has been delivered in DolbyA form (that is one reason for the 'harsh' digital sound that so many people are used to nowadays), and the listener base has become accustomed to the unnatural sound of DolbyA compression without decoding. (When any so-called 'experts' claim that material that I am suggesting is not DolbyA encoded and DolbyA encoding is too ugly to distribute -- well, I agree with part of the point -- the DolbyA material should NOT be distributed in that form. And, I am dealing with tape experts who know DolbyA very well -- and it is pretty clear that a LOT of material IS being distributed in DolbyA encoded form because of cost savings and/or laziness.)
I still remember the time when recordings could sound 'lush' instead of HF-hyped. In fact, they used to use DolbyA units to make voices sound clearer (back in the day when such devices were less common.) By leaving material DolbyA encoded, it makes it sound clearer (sometimes too unnaturally clear), but also tends not to boost the highs in a way that will cause severe clipping (because it mostly just boosts the lower signal levels, and mostly affects the highs except at very low levels for the mid frequencies.)
John
PS:
Explanation of part of the distortion between early ABBA releases and the DolbyA encoded copies:
Apparently, there is something odd being done to the M+S encoding of the recording. Normally, we think in terms of L+R (left and right), but sometimes M+S(mid and side) are useful versions of the material. M+S can be easily calculated from L+R by very simple relationship: M=(L+R)/2, S=(L-R)/2. Note that side is the difference between L+R, and that is where the oddness appearst to be. I found that by shfting the Side channel by 90degrees, that the material clears up. I am not sure the best place to do the shifting, but I think that it is best to do the shifting after DolbyA decoding. It massively clears up the results, and produces quality very similar to the old vinyl relases (without the vinyl distortions and noise.)
Since I use the ABBA material for tests, I have become somewhat technically familiar with the quality of various versions of the ABBA distributions, and some have been very disappointing. The best ones are the least accessible to the normal listener today -- both the vinyl versions and the DolbyA encoded CDs (including the 1992 ABBA Gold CD -- it IS DolbyA encoded, at least the one that I have.) And, of course vinyl isn't very available to most people any more. (You CAN get the DolbyA encoded versions relatively easily -- but decoding them is where the accessability is impeded.)
Before someone thinks -- oh, but my favorite copy, thus and thus is good -- well, nothing that I have found (including a few Polar/Polydor releases, and also the ABBA 'the complete studio recordings) are as good as the old vinyl distributions (the vinyl itself might be damaged, but the quality of the recording is pretty good) or properly decoded DolbyA encoded versions.
First, there is some kind of damage done to the masters that seems to have occurred since the early vinyl releases. Some of this damage can be undone, but is a rather extreme technical measure for most people. I explain in the paragraph at the end, which you can ignore if you want. This damage is IN ADDITION TO the frustrating DolbyA encoding.
The digital Polar/Polydor (not all are the same, but I am speaking in generalities right now) apparently were not DolbyA decoded very well, but seemed to come from a reasonably good master tape. In one or two cases -- e.g. one of hte Polar Supertrouper copies -- was done significantly better than a lot of US domestic versions.
The most potentially beautiful copy, but also the most atrociously over processed version is the 'The Complete Studio Recordings'. If they hadn't overcompressed it so severely, it would have been better than any other copy that I have. The crest factors and the peak-average ratios are atrociously small, and indicate a very good quality and too aggressive compressor being used :-). The recordings are 'pretty', but have lost some of the good parts of the ABBA sound. I have tried 'uncompressing' the TCSR recordings -- with some success, but could never regain the proper crest factors and peak-average ratio (I call it 'uncompressing' instead of 'expanding', because the goal is to undo an effect, not to add a new one.)
Except for the vinyl, and superficially pretty bad quality -- the releases like ABBA Gold 1992 are actually the best, if you can DolbyA decode them. Unfortunately, ABBA & DolbyA are not very nice friends -- ABBA is incredibly tricky for DolbyA to decode because of the mixed high pitched voices, and otherwise intense HF sound. That creates huge amounts of intermodulation, and is one reason for many ABBA releases sounding too compressed during 'crescendos' in their singing. My DolbyA compatible (not licensed or encouraged by Dolby labs) decoder DOES do a fairly good job of undoing the DolbyA encoding (much better than DolbyA HW), but still it would be much nicer to have clean copies of the pre-encoded master tapes to work with. (The compression effect when encoding/decoding difficult material for DolbyA seems similar to mild overload of tape itself... Such intermodulation effects do sometimes cause a sound that is similar to gain compression.)
So many of the ABBA releases have been needlessly damaged, and after the some 5-10copies of each song/recording that I have (probably more than that number), it is so sad to hear all of the major differences in the releases, yet KNOWING that it sounded much prettier in the studio. The saddest thing (but potentially most fortunate in the longer term) is that so much pop music has been delivered in DolbyA form (that is one reason for the 'harsh' digital sound that so many people are used to nowadays), and the listener base has become accustomed to the unnatural sound of DolbyA compression without decoding. (When any so-called 'experts' claim that material that I am suggesting is not DolbyA encoded and DolbyA encoding is too ugly to distribute -- well, I agree with part of the point -- the DolbyA material should NOT be distributed in that form. And, I am dealing with tape experts who know DolbyA very well -- and it is pretty clear that a LOT of material IS being distributed in DolbyA encoded form because of cost savings and/or laziness.)
I still remember the time when recordings could sound 'lush' instead of HF-hyped. In fact, they used to use DolbyA units to make voices sound clearer (back in the day when such devices were less common.) By leaving material DolbyA encoded, it makes it sound clearer (sometimes too unnaturally clear), but also tends not to boost the highs in a way that will cause severe clipping (because it mostly just boosts the lower signal levels, and mostly affects the highs except at very low levels for the mid frequencies.)
John
PS:
Explanation of part of the distortion between early ABBA releases and the DolbyA encoded copies:
Apparently, there is something odd being done to the M+S encoding of the recording. Normally, we think in terms of L+R (left and right), but sometimes M+S(mid and side) are useful versions of the material. M+S can be easily calculated from L+R by very simple relationship: M=(L+R)/2, S=(L-R)/2. Note that side is the difference between L+R, and that is where the oddness appearst to be. I found that by shfting the Side channel by 90degrees, that the material clears up. I am not sure the best place to do the shifting, but I think that it is best to do the shifting after DolbyA decoding. It massively clears up the results, and produces quality very similar to the old vinyl relases (without the vinyl distortions and noise.)