If I say 'F=BIL' you might work out who I was talking about
Is it like Beetlejuice, where if you say his name 3 times he appears in the thread?
That was a total misfire. My comment was intended to be somewhat wider ....e.g. about the last 3000 posts. Give or take.
IOW, I object to the bandlimiting needed to capture my information correctly. I deserve better treatment.
Sampling involves bandlimiting. (Twice). TANSTAAFL.
Always good fortune,
Chris
Sampling and nyquist has been around at least since I learned it back in ~'76.
The understanding that time varying content creates an additional constraint...that is what most did not learn.
My biggest lament is that present day engineers really have no understanding of the fundamentals. And fight tooth and nail to not learn them. They believe an FFT is...god.
Jn
Not at all.
The point has always been, when an instrument creates content that varies quickly with time, the resultant spectra must be considered with respect to the band limiting that is required for the specific sampling rate. If for example, the instrument created a fundamental frequency of 20 kHz that rose at a 5khz rate, the resultant sideband of frequency would be 25 kHz. Sampling to limit the capture to 20 or 22 kHz will force the elimination of information.
Jn
You must think me to be a religious zealot on the topic, but it comes honestly. I've seen far too many misunderstandings on the topic, going back to the first CDs (which really did sound rubbish). Most folks (like me) without a good education learned wrong-headed ideas that are hard to shake free of.
When I first learned PCM in 1970 nobody was talking about dither, although some college professors must have thought of it. We used it for military coms broadcast with no encryption, it was considered so secure. Who could get anything out of that? It's still pretty weird.
Much thanks, as always,
Chris
Honesty is perfect. It is my preference, and my only course of action.
In reviewing the audio world of sampling, I see a complete lack of fundamental understanding. I blame nobody. But I see this everyday at work.
This is totally consistent with the thinking of inductive voltage, V=LdI/dt. While correct, the actual is V=LdI/dt plus Idl/dt. The devil is in the details.
Because rate of change of the signal is not included in the bog standard teachings of nyquist limit, things are missed..
What concerns me is that some who are un-knowledgeable fight tooth and nail, instead of learning.
Jn
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Didn't the idea originate with big guns? Naval sized? Or something like an early chaotic time-to-target?
Much thanks, as always,
Chris
Don't speak for everyone here please. We all need to go through the single sideband derivation by hand.
I said most..
Not all.
Of all those here, I listen to your criticism the most. To date, you have been the most grounded.
What surprises me the most is you thinking you need to even think that you need to point out your difference,nor your excellence..
Known, and understood.
Jn
Thank you this comment gives me great pause, I guess it's the interweb effect and the mixed company here.
My wife is doing a culling of everything so the kids don't have to put it in the dumpster when we are gone, women are so practical always planning ahead.
Yep. I just went thru that as well for the same reason. When you reach retirement age, you know and feel you wont live much longer. Now making things easier for others to take over and not leaving a financial and physical mess for them to clean up.
Here, I am just downloading my experiences and thoughts. Right or wrong. Good or bad. Keeping the dream alive of ever greater realism in music reproduction.
-Richard
Here, I am just downloading my experiences and thoughts. Right or wrong. Good or bad. Keeping the dream alive of ever greater realism in music reproduction.
-Richard
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I agree. Not all hi-res recording are good, and CD recording, either.
If recording is good and the equipment is good, you can hear the improvement of sound quality.
Well, Jn, how about explaining it in layman's terms so that everyone can understand? Maybe then some will try to learn from you?
After all, this place is called "Do It Yourself Audio" and is primary for the "music lover and enthusiast with soldering iron and his first kit in his hands" type of people.
If you've come here you have to accept that and treat less knowledgeable people with respect. Telling them that they lack of fundamental understanding or throwing a bunch of formulas at them will do no good.
Just sayin'
I dont mind that others talk beyond my knowledge. Just that something needs to be done for CD to sound more accurate to real music instruments or more realistic. Lots of work-arounds have one by one addressed the worse of it and minimised them. So what if the math used is correct. Something is not right in the end result. Maybe JN is right to suspect something is missing or the timing etc.
but what ever it is, what would make it even better (CD)? more bits and higher sampling rate. OK. Good. Done that and it does work better... maybe we will never explain it fully ? Does not matter.
Seems a wider BW might help as well by indirectly moving issues further from audio. And to be able to capture the edge/ Tr accurately, at least to the ears timing resolution ability. But that isnt likely to happen for commercial reasons. But, others have also thought more is better -- 24b and 192Khz etc. So, right now, that is the best we have. But, is it the best we can do?
JN really understands the meaning of the theory and not just processing the numbers in a set formula. That is the only way to make things work better is that kind of thinking. I saw that often at LLNL. Not my area of expertise but I recognise that quality of thinking. I have to rely on test equipment and listening. Remembering this is just a hobby for me so I have not been motivated to get into the nuts and bolts of it.
We can move on and realise the CD is good but could be better. I would like to know how to make it better and not how to keep it as is. So, we have 24/96 and beyond. What else?
I suspect that our speakers have so much distortion that for many what ever is better than CD is masked. It is also an area I devoted a lot of T&M to getting lowest distortion reproducers, acoustic issues etal.
Without such, I dont know if i could tell if there was any hardware side improvements. So, I asked here to come up with new ideas to make drivers more linear.
Anyway, seems like we have hit a dead end again. But, I/Me am moving on and have not bought a CD in many years. I have always had great low distortion speakers.... and so i notice so many things on record and play back side as well as interfacing issues are not well controlled.
Cheers.
Have a great New year.
-Richard
but what ever it is, what would make it even better (CD)? more bits and higher sampling rate. OK. Good. Done that and it does work better... maybe we will never explain it fully ? Does not matter.
Seems a wider BW might help as well by indirectly moving issues further from audio. And to be able to capture the edge/ Tr accurately, at least to the ears timing resolution ability. But that isnt likely to happen for commercial reasons. But, others have also thought more is better -- 24b and 192Khz etc. So, right now, that is the best we have. But, is it the best we can do?
JN really understands the meaning of the theory and not just processing the numbers in a set formula. That is the only way to make things work better is that kind of thinking. I saw that often at LLNL. Not my area of expertise but I recognise that quality of thinking. I have to rely on test equipment and listening. Remembering this is just a hobby for me so I have not been motivated to get into the nuts and bolts of it.
We can move on and realise the CD is good but could be better. I would like to know how to make it better and not how to keep it as is. So, we have 24/96 and beyond. What else?
I suspect that our speakers have so much distortion that for many what ever is better than CD is masked. It is also an area I devoted a lot of T&M to getting lowest distortion reproducers, acoustic issues etal.
Without such, I dont know if i could tell if there was any hardware side improvements. So, I asked here to come up with new ideas to make drivers more linear.
Anyway, seems like we have hit a dead end again. But, I/Me am moving on and have not bought a CD in many years. I have always had great low distortion speakers.... and so i notice so many things on record and play back side as well as interfacing issues are not well controlled.
Cheers.
Have a great New year. -Richard
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But this thread is different from the rest of the forum apparently. It's primary function seems to have evolved into a place where obsessive egotistical maniacs can let off a little steam by waving their memberships at each other and generally behave a bit silly. I find it amusing and quite eye-opening, not at all sad.Well, Jn, how about explaining it in layman's terms so that everyone can understand? Maybe then some will try to learn from you?
After all, this place is called "Do It Yourself Audio" and is primary for the "music lover and enthusiast with soldering iron and his first kit in his hands" type of people.
If you've come here you have to accept that and treat less knowledgeable people with respect. Telling them that they lack of fundamental understanding or throwing a bunch of formulas at them will do no good.
Just sayin'
If you can prove his hearing ability is not good enough, he will stop you at all cost
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