A few lengthy comments. This is from the perspective of one, having a very large number of early stereo pressings of Decca and EMI records (the majority of the early SXL2000 series Deccas, EMI ASD 3 digit and EMI Columbia SAX) which I have ripped for my big ripping project, and two, having done significant research for my Decca book, including extensive interviews with Decca recording engineers from the golden era of stereo. I did not interview any cutting engineers.
1. As has been mentioned before, there is no controversy that companies used a variety of EQ's for their early mono LP's. The controversy is what happened after 1954, when RIAA was established as the international standard.
2. Separate topic: My experience with London vs Decca pressings (classical only) started with the work of Sedrick Harris, almost 20 years ago, who did some serious comparisons. I was just starting to go almost annually to London and so could find Decca pressings of records that I already had bought in their London version. What I found in comparing records with the same matrix information, that Deccas would generally sound better and sometimes sound the same as their London counterparts. They would, with the occasional exception of a worn Decca vs. a more pristine London, never sound worse. I was trying to find a rational explanation of this. My best attempt is the following. For the same matrix, if there was a run of X copies pressed, after they were finished, they would be labelled (at the Decca presssing facility outside London) either Decca or London. Since the US had a much bigger market, my assumption is that more copies would end up with a London label than a Decca label. Also, the earlier in the production run a record was stamped, the better it sounded (less wear on the stamper). So my surmise is that Decca's, destined for the home market were first off the press, with the larger US part of the run destined for the London label would come out last. The would explain why Deccas which were pressed earlier in the run would sound better than the Londons which were pressed later in the run. If one compared Decca and London copies that came close to the switch point, then they should sound about the same. Just my theory.
Please note that it was in my interest and my hope, that London pressings would sound as good or better than Deccas, since I already had a large number of them and they were much cheaper to buy used in the US.
3. As far as different EQ's, I asked the question of the two Decca engineers whom I interviewed most extensively. They both said that they did not know of any deviation from the RIAA EQ during the early stereo era or later. One of them, John Dunkerley, tried to arrange a lunch during my most recent visit in June with one of the few remaining cutting engineers, Tony Hawkins, who lives quite a bit outside of London, but he could not make the lunch. The focus of my book is not the EQ question, so I didn't pursue it further than asking the question to John D and Mike Mailes, the other engineer.
So for Decca, at least, I agree with Mike Fremer on the RIAA question.
4. However, there is still the puzzle which Fremer has not addressed. Does the Decca EQ or EMI EQ, etc. sound more like the original master tape for these early stereo issues. From what I can gather, Fremer has not actually listened to early Decca classical recordings to compare the different EQ's.
AFAIK, Yamada-San, head of Zanden Audio, was the first to actually experiment with different EQ's for early recordings. He did not like the sound of these early stereo recordings. He found by tweaking the EQ, he could make these early records sound much better. Others had similar results, including Roy Gregory who has done extensive listening. I was intrigued, especially for early EMI stereo (so called white and gold labels) which sounded excessively bright to me. Most, but not all early Deccas also had a brightness to me, though not as much as the EMI's.
Was there a way to compare an early record (using different EQ's) to the original master tape? Unfortunately, no. However, I found several surrogates for the master tape for a few of the many records that I had. The most ubiquitous are reel to reel versions of early Decca stereo recordings. They should give a sense of the sonics of the master tape and there are a lot of these around (7.5ips 4tr) and I have quite a few. However, the quality of the sonics of these early tapes is generally not so good. Second are the reissues on vinyl that have been done, mostly by Speakers Corner for Deccas and by several companies for EMI, including Testament, which have generally been quite excellent sounding. Third is one early Decca that was released as a Tape Project tape (15ips 2 track) taken from the original master tape. This is probably as close to the original as one could get. Finally, I have several digital files from FIM which were done for their early Decca CD releases and taken directly from the master tapes. Again, very close to the original.
After doing some close comparisons, I find that Zanden EQ's come closer to the originals in general than RIAA EQ for most of the early releases of EMI and Decca. One important caveat is that the various reissues are not of the original master tapes in their original condition, but of the original master tapes after years of play and sometimes not good storage. My understanding is that the reissues all have been tweaked by the mastering engineers, to try to restore and improve their sound. John Dunkerley complained to me about some of the reissues as not being true to the originals.
For my ripping project, where I have done all 3000 + Decca family analogue recordings (out of 8000+ done so far), for the early stereo recordings (before the mid '60's) I ripped all the early pressings in both RIAA and the Decca EQ as well as ripping the early reel to reel versions (in NAB), so I can compare them. The early EMI's to me so clearly benefitted from the EMI EQ that I didn't use RIAA for them. What I did was start from records that were clearly to my ear RIAA EQ and move to earlier and earlier records until I heard clear indications (mainly a brightness and glare) that told me the EMI EQ would be needed.
I don't have a good theory of why these early stereo EMI and Deccas sound bright. Michael Gray has speculated that the cutting amps and heads used in the early days of stereo are responsible for the bright sound in the records which are tamed by the different EQ (like a tone control?).
For records from after the mid 60's I don't hear evidence of the extra brightness and I have used RIAA for all of those records.
I had Bottlehead custom build my phono preamp with variable EQ (multiple settings for bass shelf, turnover point and treble rollover) so I can emulate RIAA or a very large number of EQ curves, both mono and stereo, including all those used by Zanden. The phono pre has both unbalanced and balanced outputs, the latter to directly connect to my Pacific Microsonics Model Two for my ripping.
Please feel free to get further clarifications of what I have done, either on this thread or by PM.
Larry
1. As has been mentioned before, there is no controversy that companies used a variety of EQ's for their early mono LP's. The controversy is what happened after 1954, when RIAA was established as the international standard.
2. Separate topic: My experience with London vs Decca pressings (classical only) started with the work of Sedrick Harris, almost 20 years ago, who did some serious comparisons. I was just starting to go almost annually to London and so could find Decca pressings of records that I already had bought in their London version. What I found in comparing records with the same matrix information, that Deccas would generally sound better and sometimes sound the same as their London counterparts. They would, with the occasional exception of a worn Decca vs. a more pristine London, never sound worse. I was trying to find a rational explanation of this. My best attempt is the following. For the same matrix, if there was a run of X copies pressed, after they were finished, they would be labelled (at the Decca presssing facility outside London) either Decca or London. Since the US had a much bigger market, my assumption is that more copies would end up with a London label than a Decca label. Also, the earlier in the production run a record was stamped, the better it sounded (less wear on the stamper). So my surmise is that Decca's, destined for the home market were first off the press, with the larger US part of the run destined for the London label would come out last. The would explain why Deccas which were pressed earlier in the run would sound better than the Londons which were pressed later in the run. If one compared Decca and London copies that came close to the switch point, then they should sound about the same. Just my theory.
Please note that it was in my interest and my hope, that London pressings would sound as good or better than Deccas, since I already had a large number of them and they were much cheaper to buy used in the US.
3. As far as different EQ's, I asked the question of the two Decca engineers whom I interviewed most extensively. They both said that they did not know of any deviation from the RIAA EQ during the early stereo era or later. One of them, John Dunkerley, tried to arrange a lunch during my most recent visit in June with one of the few remaining cutting engineers, Tony Hawkins, who lives quite a bit outside of London, but he could not make the lunch. The focus of my book is not the EQ question, so I didn't pursue it further than asking the question to John D and Mike Mailes, the other engineer.
So for Decca, at least, I agree with Mike Fremer on the RIAA question.
4. However, there is still the puzzle which Fremer has not addressed. Does the Decca EQ or EMI EQ, etc. sound more like the original master tape for these early stereo issues. From what I can gather, Fremer has not actually listened to early Decca classical recordings to compare the different EQ's.
AFAIK, Yamada-San, head of Zanden Audio, was the first to actually experiment with different EQ's for early recordings. He did not like the sound of these early stereo recordings. He found by tweaking the EQ, he could make these early records sound much better. Others had similar results, including Roy Gregory who has done extensive listening. I was intrigued, especially for early EMI stereo (so called white and gold labels) which sounded excessively bright to me. Most, but not all early Deccas also had a brightness to me, though not as much as the EMI's.
Was there a way to compare an early record (using different EQ's) to the original master tape? Unfortunately, no. However, I found several surrogates for the master tape for a few of the many records that I had. The most ubiquitous are reel to reel versions of early Decca stereo recordings. They should give a sense of the sonics of the master tape and there are a lot of these around (7.5ips 4tr) and I have quite a few. However, the quality of the sonics of these early tapes is generally not so good. Second are the reissues on vinyl that have been done, mostly by Speakers Corner for Deccas and by several companies for EMI, including Testament, which have generally been quite excellent sounding. Third is one early Decca that was released as a Tape Project tape (15ips 2 track) taken from the original master tape. This is probably as close to the original as one could get. Finally, I have several digital files from FIM which were done for their early Decca CD releases and taken directly from the master tapes. Again, very close to the original.
After doing some close comparisons, I find that Zanden EQ's come closer to the originals in general than RIAA EQ for most of the early releases of EMI and Decca. One important caveat is that the various reissues are not of the original master tapes in their original condition, but of the original master tapes after years of play and sometimes not good storage. My understanding is that the reissues all have been tweaked by the mastering engineers, to try to restore and improve their sound. John Dunkerley complained to me about some of the reissues as not being true to the originals.
For my ripping project, where I have done all 3000 + Decca family analogue recordings (out of 8000+ done so far), for the early stereo recordings (before the mid '60's) I ripped all the early pressings in both RIAA and the Decca EQ as well as ripping the early reel to reel versions (in NAB), so I can compare them. The early EMI's to me so clearly benefitted from the EMI EQ that I didn't use RIAA for them. What I did was start from records that were clearly to my ear RIAA EQ and move to earlier and earlier records until I heard clear indications (mainly a brightness and glare) that told me the EMI EQ would be needed.
I don't have a good theory of why these early stereo EMI and Deccas sound bright. Michael Gray has speculated that the cutting amps and heads used in the early days of stereo are responsible for the bright sound in the records which are tamed by the different EQ (like a tone control?).
For records from after the mid 60's I don't hear evidence of the extra brightness and I have used RIAA for all of those records.
I had Bottlehead custom build my phono preamp with variable EQ (multiple settings for bass shelf, turnover point and treble rollover) so I can emulate RIAA or a very large number of EQ curves, both mono and stereo, including all those used by Zanden. The phono pre has both unbalanced and balanced outputs, the latter to directly connect to my Pacific Microsonics Model Two for my ripping.
Please feel free to get further clarifications of what I have done, either on this thread or by PM.
Larry
