My experience from way back was old lines were moved off shore and continued to produce obsolete but popular products. My feel is local governments kicked in perks to get the employment in what would have been new "High Tech" for the region. I did get TIPxxx made in Jordan.
So next order I'll get a 741 and check the slew rate at a gain of 1. Maybe a bit more before opening it.
With the exception of better membrane materials, adhesives, voice coil formers, heat resistant isolation, magnetic materials, tighter manufacturing tolerances and improved design aids such as infinite elements modeling, and overall acoustic measuring capabilities, I am sure you must be absolutely right 🙂
Sorry guys, I am only acting on what is known at this time. We KNOW that FM distortion is generated in most op amps, especially ones designed with audio in mind. Now, since it takes special test equipment to MEASURE it, what progress has been made? Well, Ron Quan has delivered 3 separate AES papers on the existence and measurement of FM distortion over the years. He also repeated the 741 measurement that started this controversy from our paper delivered in 1976. He apparently had different results than Gerhard, as he found that I was right.
However, while FM distortion is real, it can be as low as AM distortion, comparable actually, OR with a high open loop bandwidth, virtually non-existent even mathematically. The big problem today is the distortion residual of Ron's test apparatus. It does not find much with an AD797, but it finds PLENTY of FM with parts easily available today, and could be used in mid fi audio equipment. It is ongoing research, and worth an unbiased look.
As far as I am concerned, we have gone from 'It doesn't exist', to 'It exists, but its not important.' And this view will probably evolve to 'We invented it', or 'Of course, we addressed this issue'. We just have to wait and see.
We had the same problem with TIM, starting 46 years ago with Matti Otala's original IEEE paper. Developing a TIM measurement test in 1976, that is now the world standard, and even built into test equipment today, to finally people having slew rate competitions that are probably above and beyond the needs to reduce TIM in audio equipment. We noticed this by 1978, so Matti moved to find whatever else, that we could be overlooking, and he coined the term (PIM) or FM distortion, and started a new controversy. And so it goes! '-)
Now, in 1979, I worked with Fleetwood Mac on the Tusk album, with the band members choosing early digital recording over 30ips/1/2" analog tape. I was there and I did hear the difference, so I know limits of choosing band members (of this group at least) to make this decision.
However, while FM distortion is real, it can be as low as AM distortion, comparable actually, OR with a high open loop bandwidth, virtually non-existent even mathematically. The big problem today is the distortion residual of Ron's test apparatus. It does not find much with an AD797, but it finds PLENTY of FM with parts easily available today, and could be used in mid fi audio equipment. It is ongoing research, and worth an unbiased look.
As far as I am concerned, we have gone from 'It doesn't exist', to 'It exists, but its not important.' And this view will probably evolve to 'We invented it', or 'Of course, we addressed this issue'. We just have to wait and see.
We had the same problem with TIM, starting 46 years ago with Matti Otala's original IEEE paper. Developing a TIM measurement test in 1976, that is now the world standard, and even built into test equipment today, to finally people having slew rate competitions that are probably above and beyond the needs to reduce TIM in audio equipment. We noticed this by 1978, so Matti moved to find whatever else, that we could be overlooking, and he coined the term (PIM) or FM distortion, and started a new controversy. And so it goes! '-)
Now, in 1979, I worked with Fleetwood Mac on the Tusk album, with the band members choosing early digital recording over 30ips/1/2" analog tape. I was there and I did hear the difference, so I know limits of choosing band members (of this group at least) to make this decision.
My best friend from Harman was a runner of the magic, white nose candy powder to them starting at this time and through the early 80's. He delivered to them while they were in all manner of places; concert backstage, homes, yachts, and yes, 😉recording studios!😉 We are not talking grams, but
ounces😱. Just google "cocaine effect on hearing" and well, you can see how wrong turns in the sonics department can be made.
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And 3 at a time work better than two! I have only seen some snippets on this, but am sure the meta-analysis of this could be fascinating.
My best friend from Harman was a runner of the magic, white nose candy powder to them starting at this time and through the early 80's. He delivered to them while they were in all manner of places; concert backstage, homes, yachts, and yes, 😉recording studios!😉 We are not talking grams, but
Same with "Boston", amazing how much two songs can make. My friend dealt them posh wines, what a waste. He once mentioned a full cigar box of the white stuff.
Red placebos must work better, it makes perfect sense, we already know red cars are faster.....
I do not understand why so many posters commingle things that are separate, and separate things that are conceptually together??
No, what's dumb is broad brush statements like this one, frankly.
Let's dissect this.
The presumption that opamps "must have a sound of their own" is the first part. Perhaps they do, perhaps they do not - the question is DO THEY.
The tests I suggested, the actual tests that SY did, and the ones Mooly tried were means by which to make some sort of objective determination.
The discrete vs. opamps "debate" is not at the core of the issue. Clearly just by making a circuit out of discrete devices does not imbue it with any magical properties.
Wrong. Simply an unwarranted conclusion.
IF you take the assumption as being true that SY actually DID and could hear 6 buffers and not 5 then it shows that these devices clearly do impart some change compared to a straight wire.
The issue of hearing threshold is precisely and specifically a key point. One that needs investigation.
Obviously and clearly it shows a "problem" in that 6 buffers are less neutral/transparent than 5. Therefore SY's buffers are DOING SOMETHING other than merely passing the signal.
This is a fact. Objectively.
Again, this is not the actual question, but to address this separate question, you've made a conjecture and ask "what would that prove"?
To be clear this does not "prove" anything.
Proof is much more difficult and complex to acheive.
What it would or might show is that there ARE audible differences between these two things in a given test condition. What conclusions to draw after that, remains to be seen...
AND, I certainly did NOT say "opamps are bad".
I said that opamps are audibly different.
Some, apparently are essentially "clean", "neutral", "transparent". At least in my experience. There seems to be a range of can we say "hifi merit"??
What exactly is the "correct method"??
What "proof" do you require?
You could merely try SY's experiment for yourself, and see what you hear?
That would at least show you, or anyone else trying it, where your personal threshold for "hearing" this stuff is. Right?
Now what if YOUR threshold was 10 of SY's buffers, not 6?
What would that tell YOU??
(we both know, don't we?)
WHOA cowboy!
First off, why not use a Crest amp for your subs?
And really, you say they are not the most "neutral", not the ultimate in audio quality? How so? In what way?
Which parameter or measurement would show us this?
By way of comparison which other amp can you show the parameter or measurement of which will illustrate what we "want" in an amplifier??
Please do tell!
Well not entirely true, but let's skip this...
So, your assertion is that any ESS DAC of any recent generation is the same sonically to another ESS DAC?
--------------
These sorts of statements are essentially hyperbole. Why? Because elements of what is being said are present, but they're re-assembled so as to make them exaggerated, wrong, and inaccurate.
Sorry about your frustration. I am frustrated too. Because I want to engage and harness the expertise present to stage some actual tests. And SY who was banging hard on one side of the "discussion" apparently published something that undermines his own position(s).
I'm willing to fail, to be shown that I am wrong, change my ideas and thinking, and to learn.
No, what's dumb is broad brush statements like this one, frankly.
Let's dissect this.
The presumption that opamps "must have a sound of their own" is the first part. Perhaps they do, perhaps they do not - the question is DO THEY.
The tests I suggested, the actual tests that SY did, and the ones Mooly tried were means by which to make some sort of objective determination.
The discrete vs. opamps "debate" is not at the core of the issue. Clearly just by making a circuit out of discrete devices does not imbue it with any magical properties.
Wrong. Simply an unwarranted conclusion.
IF you take the assumption as being true that SY actually DID and could hear 6 buffers and not 5 then it shows that these devices clearly do impart some change compared to a straight wire.
The issue of hearing threshold is precisely and specifically a key point. One that needs investigation.
Obviously and clearly it shows a "problem" in that 6 buffers are less neutral/transparent than 5. Therefore SY's buffers are DOING SOMETHING other than merely passing the signal.
This is a fact. Objectively.
Again, this is not the actual question, but to address this separate question, you've made a conjecture and ask "what would that prove"?
To be clear this does not "prove" anything.
Proof is much more difficult and complex to acheive.
What it would or might show is that there ARE audible differences between these two things in a given test condition. What conclusions to draw after that, remains to be seen...
AND, I certainly did NOT say "opamps are bad".
I said that opamps are audibly different.
Some, apparently are essentially "clean", "neutral", "transparent". At least in my experience. There seems to be a range of can we say "hifi merit"??
What exactly is the "correct method"??
What "proof" do you require?
You could merely try SY's experiment for yourself, and see what you hear?
That would at least show you, or anyone else trying it, where your personal threshold for "hearing" this stuff is. Right?
Now what if YOUR threshold was 10 of SY's buffers, not 6?
What would that tell YOU??
(we both know, don't we?)
WHOA cowboy!
First off, why not use a Crest amp for your subs?
And really, you say they are not the most "neutral", not the ultimate in audio quality? How so? In what way?
Which parameter or measurement would show us this?
By way of comparison which other amp can you show the parameter or measurement of which will illustrate what we "want" in an amplifier??
Please do tell!
Well not entirely true, but let's skip this...
So, your assertion is that any ESS DAC of any recent generation is the same sonically to another ESS DAC?
--------------
These sorts of statements are essentially hyperbole. Why? Because elements of what is being said are present, but they're re-assembled so as to make them exaggerated, wrong, and inaccurate.
Sorry about your frustration. I am frustrated too. Because I want to engage and harness the expertise present to stage some actual tests. And SY who was banging hard on one side of the "discussion" apparently published something that undermines his own position(s).
I'm willing to fail, to be shown that I am wrong, change my ideas and thinking, and to learn.
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I sorry too. In the end I don't think this is worth my time invested. I already said years ago we let a customer set up a test, we heard and measured nothing. There certainly is no money in this, so I guess I'll have to suffer with the way things are.
I don't doubt it.
I will tip my hat to Boston though. They actually did really try to make their live shows sound good. I remember being in middle school and one of my girlfriends had already been to many concerts by tagging along with her older sister. She did say Boston was the best sounding show she had been to. I come to find decades later that Boston actually pushed white noise out on the PA and sent roadies out to different parts of the arena with spectrum meters to try to flatten things out as much a possible. In the mid 70's this would have been much more of a PITA than today.
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Vacuphile,
Except today the majority of compression drivers are still using ceramic magnetic materials, aluminum diaphragms and the same basic device designs. Yes there are those that will use Be for the diaphragms but those are the outliers even today and some will use Neo magnetic material but when have you seen the quality of the Neo material mentioned, it could be N38 material most likely the cheapest grade. Many are still using Kapton or aluminum formers and yes the adhesives are much better today, that is a given. You can keep the plastic diaphragms in some of the newer devices, I don't really see that as any real improvement and I am a plastics guy.
I talked to Radian Audio a while ago about getting a recone kit for some very old drivers, the only problem is they changed the design since then and didn't have the older voice-coils to fit. The only difference in the past 25 years was they increased the gap dimension so they could fit larger gauge wire in the gap, not sure that was a real improvement, less flux density with more wire weight.
Except today the majority of compression drivers are still using ceramic magnetic materials, aluminum diaphragms and the same basic device designs. Yes there are those that will use Be for the diaphragms but those are the outliers even today and some will use Neo magnetic material but when have you seen the quality of the Neo material mentioned, it could be N38 material most likely the cheapest grade. Many are still using Kapton or aluminum formers and yes the adhesives are much better today, that is a given. You can keep the plastic diaphragms in some of the newer devices, I don't really see that as any real improvement and I am a plastics guy.
I talked to Radian Audio a while ago about getting a recone kit for some very old drivers, the only problem is they changed the design since then and didn't have the older voice-coils to fit. The only difference in the past 25 years was they increased the gap dimension so they could fit larger gauge wire in the gap, not sure that was a real improvement, less flux density with more wire weight.
What about planar ribbons?
New horn/waveguide designs?
They don't count?
We still use bipolar transistors, JFETs and Mosfets - aka no change in the technology?
But this is WAY off topic...
New horn/waveguide designs?
They don't count?
We still use bipolar transistors, JFETs and Mosfets - aka no change in the technology?
But this is WAY off topic...
Bear,
I don't want to go through this point by point, what I am saying is how realistic is it to gang a series of device to the N^X power and get a result where the distortion or whatever small differences now become so much greater than in a normally designed circuit, what does that really prove? If we agree that it is not additive but multiplicative in result does that really show much or are we creating a non realistic result that would never really happen in a normal audio circuit? I know that Bob Cordell has his way of increasing distortion mechanisms so he can looked at distortion on a scale that shows differences but are we really in this case of looking at opamps trying to determine the individual sonic properties of each opamp or are we doing something very different by ganging many number of devices?
If you say that you have heard equipment with opamps inside and they sound good to great to you why are we having this discussion, what are you really attempting to find? Some seem to say that all opamps are bad period, inferior devices over discrete no matter which one we are talking about, that there are no good to great sounding circuits that could possibly contain an opamp, audiophiles should not purchase devices with these opamps inside. anyone who does must have cloth ears. I just don't buy that.
On the statement about Crest, or that could just as easily been a Crown power amp, I can imagine the hoopla that would erupt if I suggested everyone should run out and use one of these SMPS powered class-d amps for a full range system, I would be branded a midfi heretic. That is a case where again all I use to hear about was look at the slew rate on these amps, they must sound good if they can put out that kind of power. While they may work just fine in PA applications I don't think many would consider such an amp in the same class as a well designed Hypex amplifier or some other high end amplifiers. JC would argue that anything not running class ab must be inferior to his 40+ year old designs.
I don't want to go through this point by point, what I am saying is how realistic is it to gang a series of device to the N^X power and get a result where the distortion or whatever small differences now become so much greater than in a normally designed circuit, what does that really prove? If we agree that it is not additive but multiplicative in result does that really show much or are we creating a non realistic result that would never really happen in a normal audio circuit? I know that Bob Cordell has his way of increasing distortion mechanisms so he can looked at distortion on a scale that shows differences but are we really in this case of looking at opamps trying to determine the individual sonic properties of each opamp or are we doing something very different by ganging many number of devices?
If you say that you have heard equipment with opamps inside and they sound good to great to you why are we having this discussion, what are you really attempting to find? Some seem to say that all opamps are bad period, inferior devices over discrete no matter which one we are talking about, that there are no good to great sounding circuits that could possibly contain an opamp, audiophiles should not purchase devices with these opamps inside. anyone who does must have cloth ears. I just don't buy that.
On the statement about Crest, or that could just as easily been a Crown power amp, I can imagine the hoopla that would erupt if I suggested everyone should run out and use one of these SMPS powered class-d amps for a full range system, I would be branded a midfi heretic. That is a case where again all I use to hear about was look at the slew rate on these amps, they must sound good if they can put out that kind of power. While they may work just fine in PA applications I don't think many would consider such an amp in the same class as a well designed Hypex amplifier or some other high end amplifiers. JC would argue that anything not running class ab must be inferior to his 40+ year old designs.
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Scott, sorry I don't understand at all.
First off "years ago" means that the SOTA has changed. What might have merely been the acceptable levels of can we say "less than perfect" are not so acceptable today, perhaps?
Secondly, you could describe in some detail the nature of the "test"?
Perhaps then it would be more credible.
Thirdly, I can play you a cut on CD that I know from personal experience will simply sound terrific, period - on almost ANY system you choose. Yes, it is a bit magical in that regard. Fwiw, it's one cut from a now old Pierre Bensusan CD. IF all that I played for you was that one cut, and you left, it's pretty likely that you would think that my system (or whatever system it was) was fantastic.
So, if one used a cut like that one, or one that happened to have inherent deficits, or played back with gear (like some SONY CD players, for example) that happen to have somewhat annoying HF artifacts, you'd NEVER hear the effects of changing out two reasonably chosen opamps, or even a slew of them.
And, I had no idea you were in this discussion in order to make money??
This is a DIY forum.
Perhaps it would be better to bow out or better, choose to volunteer what you can to actually offer to aid in the test(s) I suggested, or some other tests like that? Then we'd all benefit from more data points and maybe find out something dispositive, at least I hope so.
_-_-
Bear is a planar ribbon a new device, I don't think so. And what new horns are you talking about, the horns that seem to get the most attention are Geddes horns, his so called Oblate Spheroids, really nothing but a fancy name for a conic section horn with a nice connection to a classic compression driver with a round-over termination or perhaps a couple of other shapes that other say can't work as well. Perhaps we can call a Synergy horn something new but as far as I am concerned they are not truly new, just deviations of past ideas.
Now we can take this same concept of adding series devices and compare that to multi-generation playback where we take the output of a speaker and record that and play that back and do that again and show that as the number of passes increases distortion increases, now is that a hard concept to understand, not really, but is it a realistic way to evaluate a speaker system, I'm not sure about that, perhaps it is?
Now we can take this same concept of adding series devices and compare that to multi-generation playback where we take the output of a speaker and record that and play that back and do that again and show that as the number of passes increases distortion increases, now is that a hard concept to understand, not really, but is it a realistic way to evaluate a speaker system, I'm not sure about that, perhaps it is?
These inquisitions get tiresome, you don't bug Robert when he rolls op-amps. I gave the details, ADCOM socketed one of their preamps and sent a sampling of good/bad chips, we heard no difference. Now your going to ask me what amp and speakers I used and what were the dimensions and treatments of the room. I don't care, this falls under the difference if any could come and go at will, maybe does not exist.
Please give me the details of your attempts with your posse to make digital recordings of master tapes to me they are not credible.
EDIT - Stop everything, for Pierre Bensusan I thank you.
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