weather Joe is refering to series R for motional feedback or parallel R for minimizing speaker Z variation from resonances and their phase changes..... I agree with Max. The mid-fi products also typically have single OPS and not double or triple OPS and I have also looked at base drive fidelity.
The result is audible and measurable. 1985 and approx 1990?
THx-RNMarsh
The result is audible and measurable. 1985 and approx 1990?
THx-RNMarsh
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So you say. So after all these years you are throwing in your lot with the spirit scientists?
No misdirection. Just exercising my options. But thank you for acknowledging that I do measurements. Website is a bit dated now. Only so much time.
Richard strikes me as a very competent and professional project manager, but as an amateur engineer/scientist. Nothing wrong with that, the problems occur when he's confounding his competencies. Looks like Bob Pease pretending to sing like Jello Biafra.
So then we may conclude for certain that either a) you didn't look at AK4399's datasheet or b) You don't know where to look when you are looking at a DS. Or both a) and b).
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Ah, yes I forgot it's one of your favorite theories too.
Sorry I didn't look at one of the hundreds of available parts that you say exhibit this phenomenon. Maybe you or Terry could post the part number in your infinite wisdom before we search.
Let us take a minute and go one further than the extrapolation from a table that may or may not be correct on that forum and look at the evaluation board measurements for this 10 year old DAC part. See attached.
Looks like a huge problem.
How about a more recent $5 part in singles at DigiKey, AK4490. Second attachment. Whew, I bet my wife could hear it in the kitchen. Time to break out the TDA1541.
Sorry, I looked at high end DACs, not parts that are worse than AD1955 from 17 years ago (not that AD1955 is bad, mind you).
Sorry I didn't look at one of the hundreds of available parts that you say exhibit this phenomenon. Maybe you or Terry could post the part number in your infinite wisdom before we search.
Let us take a minute and go one further than the extrapolation from a table that may or may not be correct on that forum and look at the evaluation board measurements for this 10 year old DAC part. See attached.
Looks like a huge problem
. How about a more recent $5 part in singles at DigiKey, AK4490. Second attachment. Whew, I bet my wife could hear it in the kitchen. Time to break out the TDA1541.
Sorry, I looked at high end DACs, not parts that are worse than AD1955 from 17 years ago (not that AD1955 is bad, mind you).
Attachments
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Evidence please that I have said such a thing?
So you're saying you cannot determine whether or not the explanation offered there is correct?
I will take a look at your plots in due course, just want to deal with the customary tilting at windmills first. Where would a post from @chris719 be in the absence of windmills being tilted at?
Talk us all through what you reckon those attached plots are showing (or not showing as the case may be), I'm all ears.
You linked to a post describing this phenomenon on AK4399 and talked about it, so any normal person would infer that's what you meant. If you want to be a **** like Jakob and play word games, that's fine. Just a usual Abraxalito post.
The explanation seems correct, but if you have experience with AKM's datasheets and tables, you might think twice before you assume they captured every footnote correctly and the measurement conditions are the same for each entry. I was talking about the AKM table. Maybe you didn't read the post you linked, either.
I'm lazy because I don't scan every datasheet for every DAC ever produced, and you can't be bothered to click an attachment that you can almost read without clicking on to zoom.
Exactly what Terry claims Rob Watts was talking about. You can play your own word games. Good day.
I'm also quite aware of the following:
FFT Scaling for Noise - Audio Precision
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Not really. I do lots of T&M throughout the decades but mostly for my own enjoyment and curiosity. However, I also listen carefully to see if IT matters and how the sound changes. I guess, you could say I threw in with JC a long time ago. JC listens and he designs, both. So do I. Though JC is a lot better at it than i am. He does it 24/7. For me its just a music related hobby which comes and goes with my other interests.
As a professional R&D manager, I would ask why and how these 2 simple tests cause the acoustic output to have lower THD. There is where we might learn something.
THx-RNMarsh
YouTube
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You've lost me. I asked for evidence that I had said the words you very considerately placed in my mouth. So I take it by playing deflection games you're tacitly admitting you have none.
If you have an alternative explanation for how the table is to be interpreted, I'm all ears.
I'm lazy because I don't scan every datasheet for every DAC ever produced, and you can't be bothered to click an attachment that you can almost read without clicking on to zoom.
Which attachment was that? I certainly clicked on the ones you just posted. More debating games perchance?
Are you sure you don't have me confused with @Jakob2? Just to help you distinguish better I'll point out what he frequently points out to @Syn08 - you're projecting.
Look, I don't know what you don't understand about what I posted, nor do I care, but you seem to delight in word games, and I really don't care to play them with you. I posted the FFTs from 3 different parts, if you don't know what the "problem" being discussed was or if you have an issue with the interpretation of those, then post it and stop beating around the bush. Otherwise, shhh.
You're being highly selective about what you pay attention to. I've pointed out several instances of you playing debating tricks with me (you've done similar with @Jakob2) and mentioned which particular ones you've been engaging in (deflection and tilting at windmills in this instance). So clearly you're projecting this 'word games' notion onto me - you have no evidence for your claim I'm doing what you claim.
You posted the plots - are you saying then that AK4490 doesn't show the same issue that AK4399 shows? If that's your claim then support it from the measurements (and datasheet table(s)). Merely playing debating games doesn't help with understanding.
My job in life (even still) is to make audio stuff that works as good as I can make it. IF I could recite prayers over stuff, and it worked, I would do it. However, I don't think that would work any better than the 'holy water' that my ex wife splashed on me to see if I would burn (it didn't work either). However, I do believe in what seems to work, and I have found that too much opinion about how things work, in advance, can sometimes keep me from learning something new. Let it be a lesson to the rest of you: You must keep an open mind, or else you will miss something important, especially in audio.
Now, about the K-horns. I had them in my personal possession for about 15 years, just as Richard Heyser had at the same time. It was our reference in the 60's. BUT over the years, I found deep flaws in the character of the sound due to the large time displacement between the drivers. Finally, I sold them to a friend in 1980 or so, and switched to Rogers LS3-5A's, that were more accurate with human voice. Now, my closest associate (worked with me today) owns them, and I can go to his house if I want to hear them. They still have the same problems, but they sure beat 90% of anything else anybody has.
Now, typically, like now, I am listening to 4 Sequerra Met 7's. 2 in the front, 2 in the back as a surround. It works great for TV and fairly well for music through Comcast. It is FORGIVING and that is important with the sources available. My Wilson Sasha speakers run rings around both the Met 7's and the K-horns. But, they are too revealing for TV, even digital. I get listening fatigue with them with lousy sources like what most of us typically have available, so I use them very sparingly.
Working with John Meyer, back in the middle 70's, I learned a lot about loudspeaker design, but I never found myself alone capable of making a professional quality design. Amps and preamps are a different story altogether. Still, I strive to make even better electronics than my previous attempts, and usually I am successful, except for the CTC Blowtorch, with a built-in Vendetta Phono stage, which will probably be my final statement in that area. Lots of luck catching up, guys!
Now, about the K-horns. I had them in my personal possession for about 15 years, just as Richard Heyser had at the same time. It was our reference in the 60's. BUT over the years, I found deep flaws in the character of the sound due to the large time displacement between the drivers. Finally, I sold them to a friend in 1980 or so, and switched to Rogers LS3-5A's, that were more accurate with human voice. Now, my closest associate (worked with me today) owns them, and I can go to his house if I want to hear them. They still have the same problems, but they sure beat 90% of anything else anybody has.
Now, typically, like now, I am listening to 4 Sequerra Met 7's. 2 in the front, 2 in the back as a surround. It works great for TV and fairly well for music through Comcast. It is FORGIVING and that is important with the sources available. My Wilson Sasha speakers run rings around both the Met 7's and the K-horns. But, they are too revealing for TV, even digital. I get listening fatigue with them with lousy sources like what most of us typically have available, so I use them very sparingly.
Working with John Meyer, back in the middle 70's, I learned a lot about loudspeaker design, but I never found myself alone capable of making a professional quality design. Amps and preamps are a different story altogether. Still, I strive to make even better electronics than my previous attempts, and usually I am successful, except for the CTC Blowtorch, with a built-in Vendetta Phono stage, which will probably be my final statement in that area. Lots of luck catching up, guys!
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Maybe the first sentence I posted that you misinterpreted is poorly worded. I did not mean to insist that you've identified this "problem" with 100s of different parts personally. I meant to say, I did not go through 100s of datasheets until I found this specific part you are talking about (AK4399). I apologize for that terrible sentence structure.
Still, my point is that I did not go through dozens of datasheets and eval board measurements. I went to the EVM measurements of some modern high-end parts and stopped there because I saw nothing of concern - it is all highly likely to be inaudible.
There is still nothing of concern (IMO). The AK4490 shows some of the same behavior but less. The AK4497 shows virtually none. Why don't you go look in the evaluation board manuals and look at the THD+N vs level graphs they have, I should have posted them but they are even less interesting. You can find them for AK4399 also. The THD+N is flat until distortion (or noise) starts to rise out of the (flat!) noise at around -9 dBFS. So, if the THD+N is dominated by noise, if there were significant noise floor modulation vs level then why would it not show up in a sweep of THD+N vs level? I am sure you will correct me if I am missing something here. The THD+N vs level is ruler flat until near full scale.
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I think the term "PRAT" is a good example of the difficulties when talking about perceptual impressions and even about the related measurements.
Usage of this term was often the reason for ridicule of audiophiles/reviewers, partly for the nonconsistency wrt the meaning and further for the missing link to measured numbers, besides the obvious association with group-delay.
If someone is asking about the meaning it is IMO as difficult to explain as the meaning of the term "groove". In a german forum "PRAT" was mainly used as a synonym for the german term "Fusswippfaktor" (which means foot-tapping-factor).
As it seems that our hearing sense works like kind of a time-frequency analyzer, to look for differences in the reproduction of micro-fluctuations.
Thank you for taking the time to clarify.
This discussion (at least when I joined it after @Terry mentioned the artifact) hasn't so far been about audibility. Rather its been, all along about visibility of the artifact in the measurements. Terry said it was visible, you said you'd never seen it so I joined the fray to point to where it can be seen. Nothing has been claimed by myself, nor I believe by @Terry about whether the phenomenon is audible (or not). That's an entirely separate, but related question.
So given that you're moving the focus of discussion to 'concern' and 'audibility' can both @Terry and myself consider you now accept its visible in the measurements? If you do now accept this then my job is done in this instance.
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