Hi,
Would seem these are RIAA.
I have a notable number of early stereo Melodya (especially Shostakovitch) which definitely are CCIR. I bought them in Moskow Hand 2nd Shops in the early 90's for the second time, as the first lot was lost as a result of my flight from East Germany... Now they are in storage with my other LP's, quite a bit of recent history being symbolised by these LP's.
Ciao T
Would seem these are RIAA.
I have a notable number of early stereo Melodya (especially Shostakovitch) which definitely are CCIR. I bought them in Moskow Hand 2nd Shops in the early 90's for the second time, as the first lot was lost as a result of my flight from East Germany... Now they are in storage with my other LP's, quite a bit of recent history being symbolised by these LP's.
Ciao T
The HMV Melodiyas and Angel Melodiyas (US) were cut locally, and would therefore certainly be RIAA.
The need for CCIR 56 EQ would only apply to material cut in the former Eastern Block.
(Due to export and import tariffs, the moment they could record companies transported only the tape, even ceasing shipment of the metal-stampers they shipped out earlier). When that tape is used to create new stampers, the EQ-standard at the cutting plant is used.
The issue is how long CCIR 56 remained in use, and when CCIR supplanted it. According to Graham Slee, RIAA and CCIR are identical now. Is that correct, ThorstenL?
Phono Stage/Preamp History: Record Equalisation Curves From 78s to RIAA
The need for CCIR 56 EQ would only apply to material cut in the former Eastern Block.
(Due to export and import tariffs, the moment they could record companies transported only the tape, even ceasing shipment of the metal-stampers they shipped out earlier). When that tape is used to create new stampers, the EQ-standard at the cutting plant is used.
The issue is how long CCIR 56 remained in use, and when CCIR supplanted it. According to Graham Slee, RIAA and CCIR are identical now. Is that correct, ThorstenL?
Phono Stage/Preamp History: Record Equalisation Curves From 78s to RIAA
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Hi,
Correct. The rule is always "Who cut the master"...
It is not quite as clear cut. Especially in cases of more obscure recordings that where not expected to enjoy large scale commercial sucess only stampers or mothers (pre-stamper positives) may still have been shipped to the issuing label. Some times the dead wax gives clues in that case to those who are sad enough to know the minutae of this....
Absolutely. Again, the question is generally not who mastered the tape or who issued it, but who cut it.
Currently CCIR and IEC are identical to my knowledge, but neither is the same as RIAA, as they all added a 3dB rolloff at 20Hz over RIAA. Arguably, this difference is mostly academic.
At AMR we partly ignore IEC (our Phono is still flat at 20Hz) but we slightly boost the 40Hz range to achieve this and thus have a rolloff that 3dB at 8Hz, but we do have a little over 20dB infrasonic filtering at 1/2Hz (essentially record eccentricity and warp) which in a day and age when most speakers are reflex types is sorely needed.
As for when did CCIR56 get phased out in the Eastern block, I listed for the PH-77 manual, to my best knowledge 1975 as cutoff, this is not an exact date, more like saying some time around the mid 70's, though again, this switch was not completely universal.
For example I have not really examined Chinese LP's in detail, there where few issued but they may have remained CCIR long after 1975...
I also noted that CCIR56 was phased out in Western Europe by the early 60's, it was used mainly by German & French Labels. The French went straight to RIAA, it appears the Germans to Decca for a while afterwards before also finally switching to RIAA. The reasons are lost in obscurity, antiquity and practially all who knew are long dead. Hence at best information is anecdotal and second hand, with very few exceptions.
I can guarantee that anything issued after 1990 is RIAA and in general by the the early 80's I would expect to see almost exclusively RIAA LP's in all areas, (with the exception of a few eastern block countries), early 70's mostly for Europe and America.
In some cases however some re-issues during the RIAA days where pressed from old stored stampers that had been cut much earlier, so again one gets some outliers.
I must say this whole EQ game is really very frustrating and the fact that Labels did not care enough to tell their customers was really shitty.
But these where different times and if you look at the difference curves between the different EQ's and then at what a classic Baxandall Tone Control does, you find that such tone controls can pretty much adjust the differences out.
It is my understanding that the RCA curve was chosen by the RIAA as standard replay curve precisely because it was nicely between all curves and a small tick on the bass and treble controls could "fix" most of the remaining differences.
So that way the electronics makers would stop bitching about having to make complex Phono Preamps and make simple, non-switchable curve phono preamps (something the broad spectrum arrival of MC Cartridges a decade and a halve later promptly wrecked again) and the customer would still be able to get good sound with a minimal adjustment.
Ciao T
Correct. The rule is always "Who cut the master"...
It is not quite as clear cut. Especially in cases of more obscure recordings that where not expected to enjoy large scale commercial sucess only stampers or mothers (pre-stamper positives) may still have been shipped to the issuing label. Some times the dead wax gives clues in that case to those who are sad enough to know the minutae of this....
Absolutely. Again, the question is generally not who mastered the tape or who issued it, but who cut it.
Currently CCIR and IEC are identical to my knowledge, but neither is the same as RIAA, as they all added a 3dB rolloff at 20Hz over RIAA. Arguably, this difference is mostly academic.
At AMR we partly ignore IEC (our Phono is still flat at 20Hz) but we slightly boost the 40Hz range to achieve this and thus have a rolloff that 3dB at 8Hz, but we do have a little over 20dB infrasonic filtering at 1/2Hz (essentially record eccentricity and warp) which in a day and age when most speakers are reflex types is sorely needed.
As for when did CCIR56 get phased out in the Eastern block, I listed for the PH-77 manual, to my best knowledge 1975 as cutoff, this is not an exact date, more like saying some time around the mid 70's, though again, this switch was not completely universal.
For example I have not really examined Chinese LP's in detail, there where few issued but they may have remained CCIR long after 1975...
I also noted that CCIR56 was phased out in Western Europe by the early 60's, it was used mainly by German & French Labels. The French went straight to RIAA, it appears the Germans to Decca for a while afterwards before also finally switching to RIAA. The reasons are lost in obscurity, antiquity and practially all who knew are long dead. Hence at best information is anecdotal and second hand, with very few exceptions.
I can guarantee that anything issued after 1990 is RIAA and in general by the the early 80's I would expect to see almost exclusively RIAA LP's in all areas, (with the exception of a few eastern block countries), early 70's mostly for Europe and America.
In some cases however some re-issues during the RIAA days where pressed from old stored stampers that had been cut much earlier, so again one gets some outliers.
I must say this whole EQ game is really very frustrating and the fact that Labels did not care enough to tell their customers was really shitty.
But these where different times and if you look at the difference curves between the different EQ's and then at what a classic Baxandall Tone Control does, you find that such tone controls can pretty much adjust the differences out.
It is my understanding that the RCA curve was chosen by the RIAA as standard replay curve precisely because it was nicely between all curves and a small tick on the bass and treble controls could "fix" most of the remaining differences.
So that way the electronics makers would stop bitching about having to make complex Phono Preamps and make simple, non-switchable curve phono preamps (something the broad spectrum arrival of MC Cartridges a decade and a halve later promptly wrecked again) and the customer would still be able to get good sound with a minimal adjustment.
Ciao T
The Graham Slee link showing CCIR and RIAA as identical is wrong, then?
Phono Stage/Preamp History: Record Equalisation Curves From 78s to RIAA
Phono Stage/Preamp History: Record Equalisation Curves From 78s to RIAA
Hi,
I would say, academically speaking, yes.
However, as this only effects the presence of an infrasonic filter at 20Hz or not and Graham has not accounted for this anywhere in his table I think from his viewpoint RIAA and IEC and CCIR are identical, even if from mine they are not...
Officially most people count three time constants, in reality there are of course six...
The extra three are:
LF Rolloff of playback and/or recording Amp
HF Boost Shelf of the Cutting System (the infamous "Neumann Timeconstant")
HF Rolloff of Playback and/or recording Amp
It is routine to disregard the LF and HF rolloff which I guess is kind of "fair", though an exception is made in the IEC recommendations that actively specify LF rolloff.
The "fourth" (Neumann) Timeconstant is heavily and hotly debated.
With AMR we have implemented both standard RIAA and RIAA with Neumann Timeconstant as eRIAA easily switchable.
I must say the vociferous opposition to using the "Neumann Timeconstant" by such luminaries as Jonathan Crabbe and John Atkinson notwithstanding, subjectively it sounds more right with this, we have tested this many times.
Ciao T
I would say, academically speaking, yes.
However, as this only effects the presence of an infrasonic filter at 20Hz or not and Graham has not accounted for this anywhere in his table I think from his viewpoint RIAA and IEC and CCIR are identical, even if from mine they are not...
Officially most people count three time constants, in reality there are of course six...
The extra three are:
LF Rolloff of playback and/or recording Amp
HF Boost Shelf of the Cutting System (the infamous "Neumann Timeconstant")
HF Rolloff of Playback and/or recording Amp
It is routine to disregard the LF and HF rolloff which I guess is kind of "fair", though an exception is made in the IEC recommendations that actively specify LF rolloff.
The "fourth" (Neumann) Timeconstant is heavily and hotly debated.
With AMR we have implemented both standard RIAA and RIAA with Neumann Timeconstant as eRIAA easily switchable.
I must say the vociferous opposition to using the "Neumann Timeconstant" by such luminaries as Jonathan Crabbe and John Atkinson notwithstanding, subjectively it sounds more right with this, we have tested this many times.
Ciao T
Based on this info:
SYSTEM Treble turnover Bass Turnover Lower bass t/o
RIAA (CCIR) 2.1215 kHz 500.5 Hz 50.05 Hz
EMI LP 2.5 kHz 500 Hz 70 Hz
COLUMBIA 1590 Hz 500 Hz 100 Hz
I used Spice to create some files I ploted in Excel:
As Bass turnover is very similar in all situations, I just need to adjust some caps and resistors to get these other curves.
Looking at the first Graph, they look very similar but the second graph tells a different story. It represents the differences in dB from EMI and Columbia to Riaa EQ.
SYSTEM Treble turnover Bass Turnover Lower bass t/o
RIAA (CCIR) 2.1215 kHz 500.5 Hz 50.05 Hz
EMI LP 2.5 kHz 500 Hz 70 Hz
COLUMBIA 1590 Hz 500 Hz 100 Hz
I used Spice to create some files I ploted in Excel:
As Bass turnover is very similar in all situations, I just need to adjust some caps and resistors to get these other curves.
Looking at the first Graph, they look very similar but the second graph tells a different story. It represents the differences in dB from EMI and Columbia to Riaa EQ.
Attachments
From Riaa to EMI they are within only 3dB from 40 to 20000Hz. There is a difference but it's not extreme at all. I would ignore it.
But from Riaa to Columbia there IS a strong difference.
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Looking at the graphs we might understand that playing a Columbia eq record with a Riaa EQ phono should produce enfasis on the highs and lower bass, slightly reducing the presence band.
EMI EQ records should sound slightly dull when played with Riaa EQ.
That should explain why Miles sounds so screetchy sometimes.
I would apreciate your comments.
EMI EQ records should sound slightly dull when played with Riaa EQ.
That should explain why Miles sounds so screetchy sometimes.
I would apreciate your comments.
Just consider what the microphone’s diaphragm suffered in front of Mile’s trumpet
Regards
George
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Remember that each filter is a dynamic load for the associated amplification stage. It would depend on the type of circuit as to whether what you propose is practical or not.
I see some making light of 3dB variations - that's a doubling of the sound energy in a particular region, or halving, and nothing to dismiss.
At issue is when the transition was made to RIAA, and exactly which EQ-curve was in use, by which company/cutter.
Some appear to want to obscure the topic, and that's a shame. I feel that ThorstenL should be able to give a clearer answer than this one:
Here's the PH-77 CCIR-curve:
And here's Graham Slee's - in my feeble mind, one of them has got to be wrong in more than just an academic sense.:
At issue is when the transition was made to RIAA, and exactly which EQ-curve was in use, by which company/cutter.
Some appear to want to obscure the topic, and that's a shame. I feel that ThorstenL should be able to give a clearer answer than this one:
Here's the PH-77 CCIR-curve:
And here's Graham Slee's - in my feeble mind, one of them has got to be wrong in more than just an academic sense.:
Hi,
Actually, the PH-77 does not have a CCIR curve.
In only offers CCIR56, which is the 1956 version of the CCIR Curve. I would have to check when the CCIR recommendation switched to RIAA, AFAIR early/mid 60's.
So, there where in fact a number of CCIR curves, which differ over time. As is the case for Decca LP's. DIN has also at least two separate and different specifications.
However, the real issue is that you want a clear, unambiguous and simple answer to a question that only has answers that are subject to some ambiguity, are not always clear and certainly are not simple.
The issue starts with the simple fact that the RIAA, CCIR, IEC, DIN are bodies that formulate standards but have zero enforcement ability.
So in the end it is up to the relevant commercial (or in case of eastern europe and asia political) entities to adopt and to actually IMPLEMENT such standards. And especially the commercial entities generally did not document such standard adoption well at all.
So, you will have to live with the ambiguity or obtain false certainty from supposed authorities that give you simple answers.
In the second case go with Miguel Fermer, he says "all LP's everywhere in the world on the very day after the issue of the RIAA Standard and onwards are RIAA" and leave it at that... And then do not pay attention to the man behind the (iron?) curtain...
Ciao T
PS
You realise that G. Slee shows the equalisation curve, while the stereophile measurements show the result of using the AP2's RIAA Pre-EQ followed by the stated equalisations (BTW, I have prettier curves of this from my AP2...).
As for why G. Slee shows CCIR = RIAA without any timeline qualification, ask him.
Actually, the PH-77 does not have a CCIR curve.
In only offers CCIR56, which is the 1956 version of the CCIR Curve. I would have to check when the CCIR recommendation switched to RIAA, AFAIR early/mid 60's.
So, there where in fact a number of CCIR curves, which differ over time. As is the case for Decca LP's. DIN has also at least two separate and different specifications.
However, the real issue is that you want a clear, unambiguous and simple answer to a question that only has answers that are subject to some ambiguity, are not always clear and certainly are not simple.
The issue starts with the simple fact that the RIAA, CCIR, IEC, DIN are bodies that formulate standards but have zero enforcement ability.
So in the end it is up to the relevant commercial (or in case of eastern europe and asia political) entities to adopt and to actually IMPLEMENT such standards. And especially the commercial entities generally did not document such standard adoption well at all.
So, you will have to live with the ambiguity or obtain false certainty from supposed authorities that give you simple answers.
In the second case go with Miguel Fermer, he says "all LP's everywhere in the world on the very day after the issue of the RIAA Standard and onwards are RIAA" and leave it at that... And then do not pay attention to the man behind the (iron?) curtain...
Ciao T
PS
You realise that G. Slee shows the equalisation curve, while the stereophile measurements show the result of using the AP2's RIAA Pre-EQ followed by the stated equalisations (BTW, I have prettier curves of this from my AP2...).
As for why G. Slee shows CCIR = RIAA without any timeline qualification, ask him.
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I'm sorry, but now you're just obfuscating the issue. You know perfectly well that I meant the CCIR 56, it is what is linked to in the illustration from Stereophile.
Unless you're able to give clearer answers, I'm becoming of the opinion that the PH-77 is an EQ-adjustment component that uses some very sketchy arguments for why one needs it. There's nothing wrong with using EQ, in the 50s and 60s some records even recommend particular settings.
However, the need for this kind of equalization is not proven after 1960, and is based upon some very flimsy claims. For instance, I find it most peculiar that the claims concerning DGG can't be documented. Germany is known for keeping very exact records, and statements such as "the people who know are long dead" are just silly.
The AMR argument that this is required for fidelity in playback is becoming thinner and thinner, and the illustration below is a joke. I'm getting the impression that AMR is trying to plug a product on pretty sketchy grounds if the best you can come up with is: "So, you will have to live with the ambiguity or obtain false certainty from supposed authorities that give you simple answers."
Unless you're able to give clearer answers, I'm becoming of the opinion that the PH-77 is an EQ-adjustment component that uses some very sketchy arguments for why one needs it. There's nothing wrong with using EQ, in the 50s and 60s some records even recommend particular settings.
However, the need for this kind of equalization is not proven after 1960, and is based upon some very flimsy claims. For instance, I find it most peculiar that the claims concerning DGG can't be documented. Germany is known for keeping very exact records, and statements such as "the people who know are long dead" are just silly.
The AMR argument that this is required for fidelity in playback is becoming thinner and thinner, and the illustration below is a joke. I'm getting the impression that AMR is trying to plug a product on pretty sketchy grounds if the best you can come up with is: "So, you will have to live with the ambiguity or obtain false certainty from supposed authorities that give you simple answers."
An externally hosted image should be here but it was not working when we last tested it.
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Hi,
Sorry, but I do not. You show two sets of graphs that show very different things.
Secondly, what is documented are the official standards, they are in the public domain, please peruse them.
In addition, any number of articles and websites document a wide range of views as what curve actually which turnovers and not all agree. Equally, there is no official formal record readily accessible nowadays who use what EQ and when, however many views can be found in print and on the net.
In no small part this is due repeated ownership changes, takeovers and "cleanouts" at record companies, closures of recording centres etc. For all we know the documents may exist and moulder away in some corner of some basement (together with some priceless master tapes that have also been forgotten) or they may have been shredded. The record companies are not keen to allow access to their archives anyway, you can try if you like.
So as I said before, the information used by AMR was assembled from a range of sources, the really good ones are in institutional radio archives etc., however even their information is by inference or 2nd hand.
Much of what happened around the whole EQ story happened basically in two decades between 1950 and 1970 (roughly). Anyone working at the time then would be by now at least retirement age or older, if still alive. We have not easily found anyone to talk through who was "around" at the time.
If you know former cutting engineers who worked for DGG, Decca, Columbia etc. please introduce me.
I am as much interested in harder facts as anyone, they simple appear to be hard to come by. This may be an interesting subject for some academic research and probably very high time too, however I have no need of doing an PHD Thesis on the history of LP Equalisation, even if I had spare time...
On the other hand, the effect of the different equalisation curves is very simple to illustrate. You merely need to play an LP and switch through the different EQ's. Invariably there is good agreement among even quite large audiences which EQ is correct and I have so far not encountered any situation where the chosen EQ was one that was "impossible" for the given LP.
So, in then please try yourself. It is not that hard to modify any existing Phono Stage, or to build from ground up one that has the necessary adjustments.
Then decide for yourself. This in fact has always been recommendation.
Ciao T
Sorry, but I do not. You show two sets of graphs that show very different things.
Secondly, what is documented are the official standards, they are in the public domain, please peruse them.
In addition, any number of articles and websites document a wide range of views as what curve actually which turnovers and not all agree. Equally, there is no official formal record readily accessible nowadays who use what EQ and when, however many views can be found in print and on the net.
In no small part this is due repeated ownership changes, takeovers and "cleanouts" at record companies, closures of recording centres etc. For all we know the documents may exist and moulder away in some corner of some basement (together with some priceless master tapes that have also been forgotten) or they may have been shredded. The record companies are not keen to allow access to their archives anyway, you can try if you like.
So as I said before, the information used by AMR was assembled from a range of sources, the really good ones are in institutional radio archives etc., however even their information is by inference or 2nd hand.
Much of what happened around the whole EQ story happened basically in two decades between 1950 and 1970 (roughly). Anyone working at the time then would be by now at least retirement age or older, if still alive. We have not easily found anyone to talk through who was "around" at the time.
If you know former cutting engineers who worked for DGG, Decca, Columbia etc. please introduce me.
I am as much interested in harder facts as anyone, they simple appear to be hard to come by. This may be an interesting subject for some academic research and probably very high time too, however I have no need of doing an PHD Thesis on the history of LP Equalisation, even if I had spare time...
On the other hand, the effect of the different equalisation curves is very simple to illustrate. You merely need to play an LP and switch through the different EQ's. Invariably there is good agreement among even quite large audiences which EQ is correct and I have so far not encountered any situation where the chosen EQ was one that was "impossible" for the given LP.
So, in then please try yourself. It is not that hard to modify any existing Phono Stage, or to build from ground up one that has the necessary adjustments.
Then decide for yourself. This in fact has always been recommendation.
Ciao T
When I came to London as a student in the 1980's the very first record that I bought( in HMV in Oxford Street, not some dusty import shop in Soho) was Melodiya D08779-80, Sofronitsky playing Scriabin-you couldn't find such exotic fare in Belfast where I grew up. In other words, I bought a newly pressed mono record which had been produced from a stamper made in 1961, more than 20 years previously.
The PH-77 above is hardly the most expensive valve phono in the world but it does give you the option to try different EQ which you may not suspect you require and after all, most serious record collectors do buy 2nd hand records.Without actually trying, most discussion is mainly hot air and even in such places as the archives of HMV such documentary evidence as exists may be ambiguous if not actually self-contradictory. It is my (minority!!) view that all phono stages which aim to be remotely "high-end" should provide this facility.
The PH-77 above is hardly the most expensive valve phono in the world but it does give you the option to try different EQ which you may not suspect you require and after all, most serious record collectors do buy 2nd hand records.Without actually trying, most discussion is mainly hot air and even in such places as the archives of HMV such documentary evidence as exists may be ambiguous if not actually self-contradictory. It is my (minority!!) view that all phono stages which aim to be remotely "high-end" should provide this facility.
The issue is not whether one needs variable EQ-curves for mono-pressings from before 1960, or for pressings from the former Eastern block -- that's actually quite handy.
But AMR have been making claims about the need for similar EQ on stereo records pressed after 1960 - and most of these claims do not stand up to closer scrutiny, with many of the sources shown to being quite clear that there's no need for anything but RIAA after 1960.
It would be good to receive some other documentation beyond "it sounds better." Sure, I can EQ the frequency curve to my liking on every record I listen to, but I'm coming down on the side of Michael Fremer (not Miguel, as Thorsten seems to enjoy calling him.)
But AMR have been making claims about the need for similar EQ on stereo records pressed after 1960 - and most of these claims do not stand up to closer scrutiny, with many of the sources shown to being quite clear that there's no need for anything but RIAA after 1960.
It would be good to receive some other documentation beyond "it sounds better." Sure, I can EQ the frequency curve to my liking on every record I listen to, but I'm coming down on the side of Michael Fremer (not Miguel, as Thorsten seems to enjoy calling him.)
Yes, I agree that the claim made about stereo LP's is extremely contentious and my first instinct would be to dismiss it. Nevertheless it cannot be denied that the earliest Decca FFSS LP's sound really quite different from their reissues in quite a consistent way and one might say the same about DGG. The question as to why this is the case leads one to at least ask questions about the EQ, don't you think? American recorded RCA "Living Stereos" on the other hand do not sound so enormously different from their Victrola reissues.
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