Really? Can I ask you for instance to come up with a class AB (or class A for that matter) amp measurement that gets to this performance level?
Jan
Attachments
Last edited:
THIS! It reminds me of when the surface finish of Shakti stones was improved and sales skyrocketed!
Jan
No need to yell ! ,
since Bimo`s chart it is probably just one simulation chart ,...
but on the other hand there is around megatons of Real Life amps test measurements which shows real life THD spectrum above 20Khz , except for those D class amps .
- I have no any D class amp to made any measurements but I`m convinced that D class 20Khz + measurements will show not so representative 20Khz+ charts , with very ugly level of audio signal THD components mixed with full of switching RF carrier trash ,
where even modest but decent designed A/B class SS amp or any decent tube amp will show much much better same test results .
- on the end i want to ask you next :
Did you ever considered unwanted but real life situation that D class amp with his 20Khz + RF always wandering delta Freq .carrier outputs in function of delta Z-load can interact with loudspeaker crossover network circuit altogether with speakers cable lines and to form some non wanted resonant RF tank circuit ?
Last edited:
... working on that right now 🙂
BUT I was referring to THD vs. Freq measurements.
\\\Jens
Jan, with respect, I did not expect this kind of post - especially since in the very next one you complain about folklore. I know it's toungue in cheek somewhat but it's really not fair to complain about generalization if you have just done it - especially preceeded by some sort of 'ad hominem' attack on 'people who live in tube/SS land'. ANY??? tube amp, ANY??? SS amp? This is not engineer speak, but exactly what you complain about, folklore.
And, while at the point of folklore, measurements and class D - the class D 19.5/18.5k IMD graph WILL create folklore precisely because it again shows up to 20k bandwidth. I don't doubt that the exemplary results show also over 20k, and it's not as if AP can't do more than 20k, so fercryingoutloud USE IT and prevent folklore being created once and for all.
And as for tube vs SS sound
I for one do not care if it's tubes, solid state or for that matter potatoes doing the amplification. Neither do I take seriously people who base their views on some kind of dogma, being that one decided uppon by themselves, or one adopted for the purpose of being with the currently 'in' crowd. And, there are many here that operate on similar basis.
Dogma and folklore is generally not well received and mostly ignored on this forum, so let's not indulge in it ourselves if possible. THere are other forums for that, like the aptly named audioasylum and similar 😛
Now, that being said, I've listened to pretty much all possible combinations of amplifier technology save magnetic amplifiers and there really is no combination that is not possible. So, there are bright tube amps as well as dark SS amps and everything in-between. Some were presented to the aformentioned dogma crowd, and of course you are never going to hear 'I was wrong' because that's just not what they do, but they did remain silent - which is an interesting metric of how your amps sound. I could cite a number of examples, some rather funny (as in a customer requiring me to un-fix his preamp from oscillation because it sounded better that way - the thing to take from it being, WHY).
Regarding SY's question, if you balanced frequency response, AND damping factor of a SS and tube amp, connected to the same speakers they will sound similar but not exactly the same IN GENERAL(*), the reason being that IN GENERAL SS and tube amps will have sufficiently different topologies to implement amplification, that it will produce a different harmonic/IM structure. And, they are not going to sound that much different if at all most of the time, but certainly when pushed close to limits either statically or on transients. Yes, if we could, we would design everything perfect and there would be no difference, but we can't, not yet. In fact, much smaller differences in topology and parts do create similar effects.
Please note that IN GENERAL tube and SS amplifiers have quite different output impedances, so just getting output level and frequency response equal is not enough. Regarding that, a typical speaker, say 2-way, along with other peaks in impedance - and not necessarily on the top end, this depends on how the tweeter attenuation is done - will have a peak in the impedance right in the midrange, around the crossover frequency - and for a two-way, IN GENERAL this falls smack right in the 2-4k region where the ear is most sensitive. In many cases this is responsible for the 'magical midrange' which can often be way too magical.
(*) As they say, ALL generalizations are incorrect 😛
Last edited:
Ohh yes there was! All these post without thinking, comparing simulations with measurements, talking about class D EMI/RF with absolutely no idea how it is in reality, about class D measurements that 'hide' stuff and filter below 6.5kHz based on not understanding a basic measurement graph is getting tiring.
Seems that anybody is allowed to throw up any keyboard diarrhea (sp) with no need to check facts first. Then when called on it, wiggle out by changing the subject.
You guys are not really into audio at all. You're just into blabbering off the topic of the day.
Sometimes I need to yell, yes! 😡
Jan
My post was in the context of someone (Ralph?) saying that in HIS view all ss sounds bright. My reply was meant to show that it is a result of the fact that if you live tube, for YOU it is a given that ss sound bright, and vv. That's why I said 'relative'. I may not have been clear enough, apologies.
I am convinced that much of that tube - warm and ss - bright disappears under controlled conditions.
As to measurement bandwidth - yes the AP can do much better. But if you look at published measurements they are almost exclusively limited to 20k, independent of the class of amp. So why all of a sudden demand that for class D we measure out to, what, 100k?
We don't do that for DACs (they can have LOTS of noise from noise shaping above 20k of course); we don't do it for our streamers.
But anyway this is taking up too much of my time. I have tried to make you guys aware that time moves on and class D doesn't have to take 2nd stage from anyone anymore, not even from class A.
As an example, class D has pretty much taken over active monitoring speakers in most studios. It's now taking over hi-end as witnessed by the new top of the line products from Jeff Rowland and Burmester just to mention a few.
What is still holding it back is uninformed entrenched views that 'it can't be good because it has staircase voltage' and similar nonsense based on ignorance. But it will march on, no doubt in my mind.
Have fun!
Jan
)
Why can't we have extremely judicious use of feedback within feedback; one to lower the overall distortion and one to lower high order distortion arising out of original feedback used ? Pardon me as I dared to ask absolutely rookie question again. But since no one has complained I thought I will take a chance. 😱
Regards.
Regards.
https://www.youtube.com/watch?v=U_eZmEiyTo0
Would you like to try the AB test?
Clearly, I don’t need to take the AB test, as I have posited that all amplifiers sound the same.
What if we make it interesting, say a lifetime membership to AES?
Very well, I accept. But since we already know that I will not be able to hear a difference, I will deduce the answer with my superior powers of reasoning alone.
Alright, but I’m not sure what you mean.
But it's so simple. All I have to do is divine it from what I know of you: are you the sort of man who would connect the tube amplifier to the speakers, or the solid state. Now, a clever man would connect the solid-state amplifier because he would know that all amplifiers sound the same anyway, and a so-called golden-eared audio fool, trying to hear a non-existent difference, would almost certainly guess the tube amplifier because he is incapable of escaping his own bias.
Truly, you have a dizzying intellect.
Oh, I’m just getting started. However, since I am clearly not an audio fool, and doubtless you recognize this, it is possible that you have connected the tube amplifier, hoping that your choice will throw me off since you know that I know that all amplifiers sound the same and would guess that you’ve chosen the amplifier most commonly (but wrongly) thought of as being more neutral and less colored.
I see.
Yet still, you and your new age crystal-gazing ilk cling to the notion that low order harmonic distortion might somehow be audible, and I doubt that you could set aside your precious theories long enough to apply reverse-psychology to this experiment despite the high stakes, and so, believing that feedback is bad, despite the fact that I have proven that it is good because it reduces distortion, which I have likewise skillfully (and with citations) argued to be completely inaudible, I must therefore conclude that you have connected the solid-state amplifier.
Look! What in the world can that be?
Just a little harmless comic relief, guys 🙂
Would you like to try the AB test?
Clearly, I don’t need to take the AB test, as I have posited that all amplifiers sound the same.
What if we make it interesting, say a lifetime membership to AES?
Very well, I accept. But since we already know that I will not be able to hear a difference, I will deduce the answer with my superior powers of reasoning alone.
Alright, but I’m not sure what you mean.
But it's so simple. All I have to do is divine it from what I know of you: are you the sort of man who would connect the tube amplifier to the speakers, or the solid state. Now, a clever man would connect the solid-state amplifier because he would know that all amplifiers sound the same anyway, and a so-called golden-eared audio fool, trying to hear a non-existent difference, would almost certainly guess the tube amplifier because he is incapable of escaping his own bias.
Truly, you have a dizzying intellect.
Oh, I’m just getting started. However, since I am clearly not an audio fool, and doubtless you recognize this, it is possible that you have connected the tube amplifier, hoping that your choice will throw me off since you know that I know that all amplifiers sound the same and would guess that you’ve chosen the amplifier most commonly (but wrongly) thought of as being more neutral and less colored.
I see.
Yet still, you and your new age crystal-gazing ilk cling to the notion that low order harmonic distortion might somehow be audible, and I doubt that you could set aside your precious theories long enough to apply reverse-psychology to this experiment despite the high stakes, and so, believing that feedback is bad, despite the fact that I have proven that it is good because it reduces distortion, which I have likewise skillfully (and with citations) argued to be completely inaudible, I must therefore conclude that you have connected the solid-state amplifier.
Look! What in the world can that be?
Just a little harmless comic relief, guys 🙂
Last edited:
My apologies also if I was harsh, but I usually take your posts as examples of accuracy, but given the topic i am not surprised one gets carried away.
Certainly in my experience. Which is, if you think about it, logical, once you approach any technology with the idea of getting the most out of it.
Well, exactly to shut up the naysayers. In fact, you can reverse their arguments on them, by asking for THEIR 40k or 80k bandwidth plots. Otherwise, when it's not on the plot, people can, and will and indeed, have, put their favorite misconception there and use it against you.
Sadly, you are right. Re class D, to me this is preaching to the quire, as the daily bread is won building active PA and monitoring systems that have for years used Pascal Audio class D modules. Also, I am helping with some development of a front end for nCore OEM modules. Not to mention I still own - and probably will never get rid of - a Sony TA-N88B VFET class D amp from back in 1977, using VFETs as switches at no less than 500kHz (cinstant rate).
Jan you can yell but not at me please ! 🙂
Sorry that i must say but If someone constantly wiggle the subject and hide the D class amps real measurements facts that`s you , ...
I have impression that if I ask about simple 20Khz+ characteristic of those D class amps is like I ask about of characteristic of some protected holly cows from far India . 🙁
And yes , here to call so many known & unknown people as ignorant and @#$%... is not to good for your reputation , you know personal emotions & science have nothing in common . 😉
Over & Out !
You have neglected to quote the next sentence which puts things in the proper context - so I will repeat: while most of the time both amps will sound indistinguishable to the level one can get rid of one own's subjectivity (blind tests do this), they betray themselves when pushed harder, especially into transients and clipping. Because what I mentioned in the part you did quote.
That being said, one could go all out and get the behavior of these amps as close as possible, and IN GENERAL come up with a very big and complicated tube amp 😛
If an amp is clipping, it's too low powered for the application. That's a fairly trivial point.
If you're talking about clipping and recovery, complication will not help that. The best tube amps I know for overload recovery are actually pretty simple. You only need complication if you're chasing numbers.
If you're talking about clipping and recovery, complication will not help that. The best tube amps I know for overload recovery are actually pretty simple. You only need complication if you're chasing numbers.
Its a simulated amplifier based on some theory and now under test based on pirate rules 😉 (some form of audio signature)
Attachments
Last edited:
Mr. Banat, wouldn't you agree you're somewhat biased ?
http://www.diyaudio.com/forums/soli...-diy-amplifier-20-years-go-7.html#post3527529
(though I admire Mr. Karsten's enthousiasm, I've yet to see a shred of evidence)
