Totally out of my memory. And it was only two years ago.
Thank you Alan. Now the file links are OK.
There is also Scott’s pseudo-noise with holes (gaps) files
https://linearaudio.net/sites/linearaudio.net/files/psrnoise_flat_96_holes_0.wav
https://linearaudio.net/sites/linearaudio.net/files/psrnoise_flat_48_holes.wav
George
Phase unwrapping: if you know the frequency and when a zero crossing happens, that identifies phase. The windowing bit, its a joke for insiders.
It is, but it depends on bandwidth. Random noise always depends on bandwidth. If you don't know what the bandwidth is then you haven't looked hard enough, and you don't actually know the noise level.mmerrill99 said:
As I keep saying, time and frequency are just two different equivalent views of the same reality.
You are confusing 'I do not directly encounter it' with 'it does not exist'. If you continue to think like that you will never be a physicist and you will never understand electronics. You may even struggle to understand sound.
Have you ever encountered the number normally written as 2? Probably not. Does this number exist?
I have known EE students who could not distinguish between these two instruments. Maybe both time and frequency domains baffled them?scottjoplin said:
I thought scottjoplin was agreeing with me. However, it is true that I am not talking about what our instruments show us (or what our ears hear) but what actually is.mmerrill99 said:
Yes, having read "Helmholtz" was the reason for my sentence; besides being (presumably) one of the last polymath(s), he was actually professor for physiology.
As you have quoted my post, I assume, you might agree that asking the quy who reminds to his post (about spectral composition and other things) if he has heard about "spectral composition" is a bit funny ?!
Given the tone of your post, I assume you're upset, but I don't understand exactly the reason why.
I quoted the sentence to which my response was aimed at and if we agree that our current understanding (and the according models) include that our hearing sense can't work as a pure frequency analyzer but uses constantly temporal informations, then it is fine.
I surely did not intentionally misinterpreted your post and if I misunderstood, please just simply state it.
Ah do explain the joke - this thread could do with some levity but if you just misspoke, it's Ok to admit that too.
It appears that you are talking about the bandwidth of the noise & not the bandwidth of the FFT bins. Are you?
I don't think it's worthwhile continuing along the time frequency discussion
Looking at the simulations for the nonoiser whats the resistor value for r7? I'm thinking of building this to power 5v supply for a usb board in a dac would this regulator be good for this use?
Yes, "spectral decomposition" would have been a better word in another context.
The joke about windowing is lame if I have to explain it. Because of the way the ear works, all 'bandpath filters' operate continuously, so each open its window the moment the right frequency arrives (hence the 'distributed phase sensitive incident driven windowing'). This is a major difference with an FFT.
The joke about windowing is lame if I have to explain it. Because of the way the ear works, all 'bandpath filters' operate continuously, so each open its window the moment the right frequency arrives (hence the 'distributed phase sensitive incident driven windowing'). This is a major difference with an FFT.
Howie,
I have listened to both of Laurie Spiegel’s albums a few times now, and each time they sound very different. A good sign. Her music is akin to the mathematical beauty of Bach from a late 20th century feminist perspective. Such a refreshing change. Now looking forward to hearing Pauline Oliveros for the first time. Think I will wait a little longer, the suspense is worth it.
I also listened to that Clara Mondshine piece on YouTube. Very interesting, like a lot of the more experimental work in the 1980’s. A sonical treat, and I thank you for it.
Oh goodness, this is the Blowtorch thread, must talk about amplifiers ......... 🙂
ToS
RIP Jack Renner...
Howie
I also had occasion to work with Jack. He was a great guy.
Both are relevant. The noise grass at the bottom of an FFT plot depends on the bin bandwidth. If someone says 'noise is 10uV' then you have to ask him what the bandwidth is if you want to know whether this is a high or low level of noise. Of course, in some cases the bandwidth is assumed (e.g. 20kHz for audio?) but in order to understand noise you have to know that bandwidth matters.mmerrill99 said:
Don't take everything too literally - the point is this a stream of electrical nerve impulses arrive at the auditory cortex - how does it know that this impulse belongs to the baritone & not the double bass - there is no identification tag riding along with that electrical impulse? The impulses are continually being sorted/categorized into the relevant auditory stream.
To make it more realistic for you - a bass string is plucked - a fundamental & harmonics are produced. These sounds arrive at the ear mixed with all the other concurrent sounds that have occurred at the same time in the orchestra. So what arrives at the ear is a complex mix of pressure waves which gives rise to nerve impulses. How does auditory perception know what are the impulses that belong to the harmonics of the double bass string pluck?
This seems effortless because we are not consciously aware of the processes involved. We only become aware when something goes wrong as in an auditory illusion, or our attention is suddenly drawn to a sudden, startling sound or when listening to our playback system is uninteresting or fatigues us or the alternative when it is interesting, natural & relaxing to listen to.
Forgive my ignorance but isn't the 'grass' in an FFT spanning the full bandwidth of the FFT?
The dB level that this 'grass' is shown on a FFT plot is not the actual noise floor dB level
Sine waves (approximately). Approximately, because they are decaying and so do not have a single frequency each.mmerrill99 said:
What do you mean by "actual noise floor dB level"? The line in each bin tells you how much stuff there was in that bin. If the stuff was actually random noise, then how much there is in each bin depends on the width of the bin.
I don't know, but it does, perhaps by correlation?
😀 I was going to mention earlier how the timbre is made up, but forgot.
You are hung up on sinewaves & will never understand Auditory Scene Analysis which is what I'm describing if you don't let go of your attachment to sinewaves
How does auditory perception know that the next bass note pluck is part of the same auditory stream? Where is that correlation made & how?
Both you & DF96 need to think at a finer level granularity (rather than sinewaves) to grasp ASA. This is not a criticism or insulting to you or him - I'm just trying to shows what ASA is about, AFAIK
What is the point of all this? Why are you here? To learn something, or just endlessly troll? You appear disinterested in or unable to carry on a technical discussion, so, what's the point?
Ok, example - FFT grass is plotted at -130DB - is the noise floor of the DUT -130DB?
I've already said I don't know, the brain using brain power? What do you want from me? 😉 BTW, I see you've mastered the Socratic method 🙂
Is "auditory perception" a little man in your brain who knows things? Does it talk to you? Does it tell you things?
Seriously, please leave homunculi out of it, there is not a being called "auditory perception" that "knows" anything.
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