So ?
(you'll never see me post the 5534 is the 3d best thing after hard-ly-adult 1-888 and web chat)
I found something else without looking too hard. See images.
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I don't think Jay wants to cheat. I think he is going out of his way not to cheat because this isn't about winning for him, he seems more interested if trying to discover truth for himself.
Also, although we have a lot of people knowledgeable about audio here, much less seems to be known by most about how even very scientific brains work, that is to say, the part working away hidden in the background. As with many other things, it is human nature to look for the worst in other people, as being duped can be very costly. We tend to have a hyperactive cheating detector that often errs on the side false positives. And we often tend to be overconfident that our intuitions about danger are correct. Makes sense, right? At least out in the jungle. In addition, others in a given social setting don't want to appear as especially gullible, as doing so would tend to diminish their social status and respect from others. Therefore, often the easiest and safest things to do is to align with the most vocally critical sub-group, thus reducing one's potential exposure as one of their targets.
Thanks for sharing.
Problem with bipolar IP OPA's is the noise current. I think about the best you can do with the average MM cart is 77-79 dB S/N because of that. A good JFET will get you <1nV/rtHz and negligible noise current. Parallel a few and you are in 85 dB ref 3mV with a real world cart and with the inputs shorted (Stereophile's preferred test method) you are at 88-90 dB.
(Moderators: subscript and superscript options in the fonts would be great! Unless I just can't see them)
Yes, phono input, mic input, and DAC I/V are the three most demanding transistor locations in audio. Then the output transistors on your power amp. 🙂
If your eyes are on performance first and circuit aesthetic last, modern audio opamps are the go-to for so many locations. One moves away from them (and/or adapts their use into a greater whole) when the circuit demands so. Goal directed design. 🙂
If your eyes are on performance first and circuit aesthetic last, modern audio opamps are the go-to for so many locations. One moves away from them (and/or adapts their use into a greater whole) when the circuit demands so. Goal directed design. 🙂
Understood. A lot more in the book about such matters. However, I was careful to recommend it as a good starting point only. Part of a process of getting up to speed with what is already known, and where the boundaries areas are for more original R&D.
You can do it with tags. Use square brackets for <sub> and <sup> with the usual closing tags, </sub> and </sup>
Bear you have a very nice sound comparison system, better than almost anyone here. When I do sound comparisons, of op amps for example, I use a STAX Lambda headphone set with a direct drive fet-tube amp and no transformers, a dual 10 turn wirewound pot and the best connecting wire that I can get hold of. This is not my normal listening set-up, because it is too limited to enjoy over time, but if I want to make a serious comparison, that is what I use.
What? You think there are nonlinearities that are inducing only "FM distortions" and no "AM distortion"?
Or you are talking about "linear distortions"?
No Waly, I just suspect that our ears detect FM distortions different than AM distortions. If this is so, then that is a good answer why some op amps can measure OK, but sound different or even wrong.
Ummm?
Say what?
You complained that no one said what their system is/was.
What's yours?
And, by way of anecdotal tales I explained why I am interested in the topic and how that came to be.
In your world, can I presume, the LME part ought to be "best" since it sports the lowest spec sheet distortion spec??
And there is nothing that I said about the 5534 being "3rd best" anything. I merely stated that it was the stock part, and switching out the stock opamp for the others changed the sound. All of the other opamps did NOT sound the same.
Do you think they ought to have??
So what are you trying to say about opamps??
_-_-
Good choice, John!
The best Stax set up I have ever heard was at a booth that Todd Garfinkle had at some show, with his recordings, and some large diaphragm version of the headset that he said was not generally available outside of Japan...
Thanks for the kind words about this system.
It's not necessarily the best, or the best that I can muster. It's what I am using now. Pretty good, and seems to accurately reflect the GIGO paradigm very well.
I posted it because Jacco seemed to question if anyone trying out different opamps actually had anything that might be considered "good".
Hoping that someone has something substantive to bring to the table on this apparent audible difference between supposedly vanishingly low distortion opamps. As in, why should the AD797 sound any different than the LME49710, isn't the distortion essentially below the noise floor?? Etc.
The kicker here is that the opamp (yet unamed) that sounded by far the best is not the one that has (on the surface) the "best" specs - certainly not lowest noise floor nor lowest distortion spec.
Groner's extensive tests, when I recently looked at them, I was unable to discern WHY or WHAT was different that could be used as a predictor. Frustrating and confounding. (at least two of the opamps I used were present in his tests)
_-_-
This has been discussed before extensively. The actual published evidence (from even their own sources) contradicts what they claim. I can't figure it out, low open-loop BW, low feedback, tube amps, etc. were far worse than modern IC op-amps, the data is right there.
You forgot to add thermal distortion, Scott. 🙂
I wonder how much is nostalgia or some form of emotional investment and how much is "Not invented here".
I wonder how much is nostalgia or some form of emotional investment and how much is "Not invented here".
Forget about flawed conjectures and hypotheticals... you're an expert, what in your view would cause a properly used AD797 to sound different (audibly so) than an LME49710 (or any other suitably high performing opamp of your choice)? Assume that they are used "properly".
Anything?
Ought they sound indistinguishable?
Let's be serious here.
Anything?
Ought they sound indistinguishable?
Let's be serious here.
DC input coupling is not possible unless you accept the hit in noise figure
by source feedback resistors. You don't want to run them at Idss.
I'm just doing something similar 🙂
< https://www.flickr.com/photos/137684711@N07/29193737144/in/datetaken/ >
same board, two options to populate. The 3rd will depend on the outcome of the first 2.
Intended for measurements.
regards, Gerhard
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Why is that? Running close to Idss has the advantage of higher gain in the jfet stage and also slightly lower noise (decreases with the 1/4 power of drain current). However, the LF 1/f and GR noise can be larger.
In my experience (I have played a little with BF862 and the CPH5905) DC coupling is possible but it doesn't make much sense; reason is, if the low noise gain stage is single ended, gain fluctuations at very low frequencies (mostly of thermal origin) will translate in output near DC flickering that need to be filtered out by a high pass circuit. There goes the DC coupling.
Differential input circuits don't have this issue, so they can be DC coupled, since the gain fluctuation apparently cancel out (and the common mode fluctuations can be ignored), but then there's a 3dB noise penalty for the differential stage, since the noise in the two branches is not correlated.
The gain fluctuation in single ended stages is not specific to jfets. It happens in bipolar low noise, high gain, single ended stages, as well.
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