I think Bonsai states quite forcefully that Lipshitz (1979) was the first publication that got all three time constants correct AND presented equations. But that's a long time after 1957.
The three time constants are a given by definition of the specification, 3180 usec, 318 usec, 75 usec. what's there to getting them right? Why is this some kind of rocket science, we put men on the moon and rooms full of French mathematicians computed artillery tables in WW1 accounting for coriolis force, etc.?
Here it is. The letter was from EMI, as you might expect.
WIRELESS WORLD: Technical and experimenter magazinefrom the UK 1913-1986
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For completeness, with all the figures and tables at the end.
It's exhausting just to look at all these equations. You have
to give SL credit, as well as his proofreader.
https://www.pearl-hifi.com/06_Lit_A...s/Lipschitz_Stanley/Lipshitz_on_RIAA_JAES.pdf
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Why is that important? That could be the topic for a (J)AFS, but not necessary for JAES.
One thing I really dislike about AES is their lack of a sense of humour while attempting to handle audio engineering as a science. They end up being self directed and sufficient, making everybody outside their closed circle unhappy; this includes both the JCs and the SWs of the world.
If AES would vanish tomorrow, I don’t think I’d shed a tear. They are to me as useful as the Aramaic language. Interesting, perhaps, but I could certainly live without happily ever after.
P.S. Disclosure: I was a member for 6 or 7 years, I gave up when I realized the only papers I was on rare occasions reading were from the library, published 20 years ago or earlier (and mostly out of a historical curiosity). Which shows once again that “audio engineering” (defined as the overlapping of Electronics and Acoustics) is dead and buried.
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Read the abstract, so now we have op-amps with 1000V/us slew rates and 250MHz unity gain BW. This stuff is no longer relevant, get over it and move on. Folks can't get away from the logical fallacy, the uA741 is an op-amp so all op-amps behave like uA741's.
I agree. I am not impressed with AES, nor am I impressed with IEEE.
There have been recent IEEE pubs that have been, shall we say, beneath dignity.
Jn
IEEE is huge, and the size comes with an unavoidable balance between excellent and crap. I find remarkable that the ratio remained approximatively constant over the last 25 years since I am a member, and about the same as in other well known associations/societies (ACM, AIP) that I frequent. IEEE has this extremely annoying segregation of its library to members, without any option to subscribe (as an individual) to another IEEE society body of knowledge without paying that IEEE society full membership. Otherwise, $15 a pop.
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For tech I am interested in, what I have seen has not floated my boat.
Specifically, some stuff I am significantly beyond the IEEE people so should not be dissapointed. However, write ups that should be good on some topics...are dismally incorrect.
My expectation is that they should be the best of the best...of the best.."with honors"...sir...
That I find stupidity...well, color me...unhappy.
Jn
I quit the IEEE when they dropped the group insurance benefit for retirees. They actually think there is a non-financial benefit for being a member?
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You could probably get the life membership status when reaching 65, so membership would come essentially at no cost? Only 35 years of membership would be required.
I did not care to apply for the IEEE senior member status, and will probably quit when I will retire.
I am not so sure that 0.1dB tolerance for an RIAA filter will do it. I mean, what is the RIAA curve of the Ortophon or Westrex or Sculley-Nuemann system? They may have a wide error as 1% parts were not used, I bet. 5% and 10% R and C were very common back in the day. And variations in the cutter head?
Plus, what was the variation from cutter system to another cutter system?
Shouldnt we make the playback curve actually fit the pre-emph/cutter system instead of a mathematical curve/formula for true accuracy?
Where can we find the RIAA curve of a measured cutter system? And, make you playback fit THAT curve.
Especially likely to have large deviation from RIAA of the cutter is at the higher freqs.
Vinyl frequencies: Just wondering.
THx-RNMarsh
Plus, what was the variation from cutter system to another cutter system?
Shouldnt we make the playback curve actually fit the pre-emph/cutter system instead of a mathematical curve/formula for true accuracy?
Where can we find the RIAA curve of a measured cutter system? And, make you playback fit THAT curve.
Especially likely to have large deviation from RIAA of the cutter is at the higher freqs.
Vinyl frequencies: Just wondering.
THx-RNMarsh
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I have been a Life member of the IEEE for the last dozen years or so, and I paid my dues as a member for at least 40 years before that. I would not mind being a Life member of the AES, for the same reason, but they never gave me a chance. I didn't know the right people, I presume.
The purpose of an ACCURATE RIAA is CONSISTENCY. If it is OK, then your frequency response can always be same as another accurate RIAA phono preamp, and then IF you hear a difference, then you could not blame it on frequency response differences, and this is important in the Lipshitz world of ABX differences, that implied that most differences in audio products were frequency response variations between compared devices.
The purpose of an ACCURATE RIAA is CONSISTENCY. If it is OK, then your frequency response can always be same as another accurate RIAA phono preamp, and then IF you hear a difference, then you could not blame it on frequency response differences, and this is important in the Lipshitz world of ABX differences, that implied that most differences in audio products were frequency response variations between compared devices.
Richard. Look at the work George, Scott and others are doing here Cartridge dynamic behaviour the errors are not a wild as you suggest. And the mfrs did use close tolerance parts, lots of feedback and careful adjustment to get accuracy. Much the same as tape recorders. And really poor by digital standards.
The point of this is that he measured and found a large % of the RIAA EQ amps were well out of spec because designers had made simplifying assumptions (in the all active designs).
Baxandall challenged him on the complexity of his derivations blah blah and showed a simple split active/passive EQ that was accurate - but sacrificed 18 dB HF headroom.
Quite why people were not getting it right, I don’t know - especially if the all active network formulae had already been published in 1957. But, the Interesting point is that some guy published equations that were wrong and was corrected 22 years before Lips 1979 paper, when people were still making the same mistake.
(Nothing forceful about my take on it - just a summary of the intro in his paper
).
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??? I am not talking about the phono cart. in the slightest. ???
I said cutter system EQ -- how close is IT to RIAA. Not very close at top end from what is said on link I showed. Did you read it? Did you read what I said, also?
Maybe you were thinking of someone else?
BTW- as far as LP playback goes, I used only 100% passive RIAA. Discrete with HV rails. More benefits than just accurate RIAA. I see no reason to change that topology.
THx-RNMarsh
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Grounding issues?
it's something contentious to talk about that isn't against the rules- Status
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